Urban Agriculture Issue - LSU AgCenter Agriculture Issue. 2 Louisiana Agriculture, ... Please give credit to the author and to ... James F. Beatty and Eric C. Achberger

Louisiana Agriculture, Spring 2001 1

Spring 2001Vol. 44, No. 2

Urban Agriculture Issue

2 Louisiana Agriculture, Spring 2001

EDITORIAL BOARD:David J. Boethel (Chairman)Linda Foster BenedictPat BollichJames ChambersBarbara Groves CornsCaye DrapchoJane HoneycuttRichard F. Kazmierczak Jr.T. Eugene ReaganDavid Sanson

Published quarterly by the LouisianaAgricultural Experiment Station,Louisiana State University AgriculturalCenter, Baton Rouge, Louisiana.Subscriptions are free. Send requestsand any comments or questions to:

Linda Foster Benedict, EditorLouisiana AgricultureP.O. Box 25100Baton Rouge, LA 70894-5100

phone (225) 578-2263fax (225) [email protected].

www.lsuagcenter.com

EDITOR: Linda Foster Benedict

CONTRIBUTOR: Jane Honeycutt

PHOTO EDITOR: John Wozniak

DESIGNER: Barbara Groves Corns

The mention of a pesticide or use of a tradename for any product is intended only as areport of research and does not constitute anendorsement or recommendation by the Loui-siana Agricultural Experiment Station, nor doesit imply that a mentioned product is superiorto other products of a similar nature notmentioned. Uses of pesticides discussed herehave not necessarily been approved by govern-mental regulatory agencies. Information onapproved uses normally appears on the manu-facturer’s label.

Material herein may be used by the press, radioand other media provided the meaning is notchanged. Please give credit to the author and tothe publication for any material used.

Louisiana State University AgriculturalCenter, William B. Richardson, Chancellor

Louisiana Agricultural ExperimentStation, William H. Brown, Director

The Louisiana Agricultural ExperimentStation provides equal opportunities

in programs and employment.

R. Larry Rogers, left, presents the Distinguished Service Awardfrom the Sweet Potato Council to Larry Rolston, a former LSUAgCenter entomologist. Rolston, who could not attend thecouncil’s recent meeting, was the creator of the Beauregardsweet potato, released by the LSU AgCenter in 1987.

Larry Rogers RetiresAs LSU AgCenter Vice ChancellorMississippi’s gain is Louisiana’s loss with the March 1 retirement of R. Larry Rogers

as director of the Louisiana Agricultural Experiment Station and vice chancellor of theLSU AgCenter. Rogers is in the process of moving back to his family farm across theborder near Prentiss.

Rogers had been with the LSU AgCenter nearly 35 years. The job he held longestwas resident director of the Northeast Research Station, which includes sites at bothSt. Joseph and Winnsboro, from 1974 to 1994.

“Larry made a big impact on agriculture in this region – and all over the state,” saidRay Young, farmer and agriculture consultant from Wisner. “He believed in researchthat was relevant. Agriculture would have been on the wane without him.”

While at the Northeast Research Station, which serves an 11-parish area thatencompasses two of the major agricultural regions in Louisiana, Rogers increased thenumber of senior research faculty from four to eight, increased the research staffs andadded new facilities. Research projects were expanded to include most aspects of rowcrop production and forages.

“One of his strengths was selecting top quality people to work for him,” said CarterWebb, a farmer from Tensas Parish, who raises cotton, soybeans and grain sorghum.“No one at the station was ever too busy for a farmer who came by with a problem andneeded advice.”

Rogers attended Hinds Junior College and Mississippi State University, where hereceived a B.S. degree in plant pathology and weed science in 1964.

After receiving hisPh.D. from AuburnUniversity in plant pa-thology and weed sci-ence in 1967, he cameto LSU as an assistantprofessor in the De-partment of Plant Pa-thology. He was pro-moted to associateprofessor in 1972 andprofessor in 1976. Hisresearch focused onsoybean weed controlresearch.

From 1988 until1991, Rogers’ dutieswere expanded to in-clude the Sweet PotatoResearch Station atChase.

In 1995, he movedto Baton Rouge tobecome the LSU

AgCenter’s vice chancellor for administration. In 1996, he was named vice chancellor forresearch and director of the Louisiana Agricultural Experiment Station.

“His expertise, administrative ability and dedication to agriculture helped redirectresearch resources to effectively and efficiently meet the changing needs of the state’sproducers,” said William B. “Bill” Richardson, chancellor of the LSU AgCenter.

William H. Brown, formerly associate director and associate vice chancellor, hasbeen named as Rogers’ replacement. Linda Foster Benedict

Photo by Mark Claesgens



Volume 44, Number 2, Spring 2001

Page 6

Page 18

SCIENCE NOTES

Page 26

CONTENTS

4 PerspectiveR. Larry Rogers

6 Fire Ant Control in Urban AreasLinda M. Hooper-Bùi

9 Formosan Subterranean Termites in LouisianaW. Ramsay Smith, Dennis R. Ring, Gregg Henderson, Qinglin Wu and Michael A. Dunn

11 Termites Under the WeatherGregg Henderson

13 Rural Land Values at the Urban FringeLonnie R. Vandeveer, Steven A. Henning, Huizhen Niu and Gary A. Kennedy

16 Water Quality and the Tangipahoa RiverCaye M. Drapcho, James F. Beatty and Eric C. Achberger

18 Insects Incriminate Poachers of Louisiana WildlifeErin J. Watson

21 Taking the Bite Out of MosquitoesC. Dayton Steelman and Dennis L. Wallette Jr.

22 Nonpoint-Source Pollution—Urban StyleMargaret Frey

23 Fertilizer Spreaders for Home LawnsRichard L. Parish

25 Horticulture in the CityGordon E. Holcomb, Allen D. Owings, Dale K. Pollet, Roger A. Hinson, Edward W. Bush, Jeff S.Kuehny, James McCrimmon, Seth J. Johnson, Peggy Cox, Drew Bates and Timothy J. Raiford

5 LSU AgCenter Urges City Dwellers To Unite for Fire Ant ControlLinda Foster Benedict

12 Termitarium Reveals Termite HabitsGregg Henderson

20 Forensic Entomology Aids Crime InvestigationJeanine Tessmer

20 C. Lamar MeekLinda Foster Benedict

24 Creamery Provides Rich Source of Research InformationRick Bogren

Page 10

ON THE COVER:


A growing population with added economic activity in urban areas influences ruralland markets at the rural-urban fringe. LSU AgCenter economists keep track of thisthrough research. Some of the highest priced land is north of Baton Rouge featuringup-scale homes and a golf course. See page 13. Photo by John Wozniak.


If you reflect on this definition, youwill find that the diversity of Louisiana’sagriculture derives from two primarysources.

Louisiana farmers are engaged inthe production of many agriculturalcommodities. Timber, cotton, sugarcane,rice and soybeans are the major plantcommodities, but perhaps as many as100 other agronomic and horticulturalcrops go into the agricultural mix, whichannually generates $2.5 billion to $3billion of income for farmers. Poultry,beef cattle and dairy are the primaryfarm animal enterprises, but horses,

sheep and swine also generate about $1billion a year in farm income. Aquacul-ture enterprises such as catfish, crawfish,alligators and other fisheries and wildlifeenterprises now generate about $500million a year in income for farmers andlandowners. Collectively, the productionof this diversity of animal and plantcommodities generates $4 billion to $5billion per year in farm income thatcomprises the real economic base formost rural communities in this state aswell as employment for thousands ofothers in urban areas engaged in theproduction of machinery, supplies andservices needed to support production ofthese agricultural commodities. Produc-tion of this vast array of agriculturalcommodities is possible because of therich natural resource base in Louisianaand a favorable temperate to subtropicalclimate.

The greatest and least-appreciatedsource of diversity in agriculture relatesto the myriad of off-farm activities thatsupports agricultural production –transportation, storage, processing,marketing and use of agriculturalcommodities and products derived fromthem. The social and economic impactsof agriculture are far greater off the farmthan on the farm. Agriculture and relatedactivities constitute about 16 percent, or$1.5 trillion, of the total U.S. economyand provide employment for approxi-mately 17 percent of the U.S. work forceor about 23 million jobs.

The LAES is charged by federal andstate legislation to conduct research thatsupports agriculture in the broadest senseof the word. Our forefathers made thedecision more than 100 years ago, in1887, to invest public federal and statefunds to support agricultural researchwith the expectation that the technolo-gies derived from this research wouldcontribute to economic development, animproved standard of living, enhancednational security, and the conservationand protection of natural resources.

R. Larry Rogers, Vice Chancellor and Director,Louisiana Agricultural Experiment Station

Agriculture is a diverse and dynamicactivity that encompasses the scienceand art of managing, protecting andconserving natural resources such assoil, water, air and sunlight toproduce plants and animals thatprovide food, clothing, shelter andother amenities for man. Agriculturealso includes forestry, fisheries,wildlife, human nutrition, appareldesign, ornamental horticulture,gardening, and development ofhuman and community resources.Moreover, the term includes amyriad of agriculturally relatedbusinesses such as those involvedwith banking and finance, foodprocessing and packaging, marketingand distribution, farm structures andequipment, and agricultural chemi-cals and fertilizers. Thus, agricultureis intimately intertwined with local,state, national and internationaleconomics.

R. Larry Rogers

Perspective

iversity is a word used frequentlyin discussions related to social, environ-mental and economic issues. The worddiversity implies variety, inclusivenessand comprehensiveness, qualities thathave the capacity to lend strength to anindividual, an organization, a system oran entity. Therefore, diversity is consid-ered a highly desirable quality. Amongother things, it imparts to those individu-als, entities and systems that have thischaracteristic the ability to prepare forand respond to opportunities andchallenges more effectively and compre-hensively than those lacking this quality.

Diversity can certainly be used mostappropriately in describing agriculture inLouisiana and research programs of theLouisiana Agricultural ExperimentStation (LAES). One of the greatestchallenges the LAES task force chargedwith developing a strategic plan titled“Focus 2000: Research for the Twenty-

D

first Century” encountered was develop-ing a statement that defined the wordagriculture. I think it is appropriate toinclude that definition because itexplains why diversity is an integral partof agriculture in Louisiana.

R. Larry Rogers

Agriculture:More ‘Urban’ Than You ThinkAgriculture:More ‘Urban’ Than You Think



This investment of public funds hasserved society exceedingly well. Duringthe past century, the percentage of theU.S. population directly engaged inproduction agriculture has declined fromabout 50 percent to less than 2 percent.The needs of 280 million people arebeing met using less land than wasrequired for a population of 75 million in1900, and more than 20 percent ofcurrent production is exported. Theaverage U.S. family can access thegreatest variety of the safest foodavailable anywhere in the world usingonly about 10 percent of their totaldisposal income. These factors haveplayed absolutely essential roles indramatically improving the standard ofliving, the health and the longevity ofAmericans over the past century.Clearly, our forefathers’ expectation thatinvestment of public funds in agricultureand agricultural-related research wouldpay big dividends for Americans hasbeen realized much more effectivelythan they could have possibly imagined.

The LSU AgCenter administrationbelieves that accountability is part of ourresponsibility as public servants andstewards of public funds. LouisianaAgriculture is one of the ways weattempt to keep the citizens of Louisianainformed about programs and accom-plishments of this organization. Thisissue focuses on some of our programsand accomplishments that relate to thecity dweller as well as to our moretraditional farm audience. Included arearticles about our research in mosquitocontrol and forensic entomology. Otherresearch efforts that evolved out of moretraditional agricultural programs includefire ant control and the battle beingwaged with the Formosan subterraneantermite. Other issues of this magazinehave focused on food safety, compostingand human ecology – topics that directlyaffect both the urban and rural Louisian-ian. If you are interested in receivingback issues, please contact themagazine’s editor.

We hope you enjoy reading thisissue. Agriculture is more “urban” thanmany people realize. We welcome yoursuggestions for improving the relevanceand effectiveness of our researchprograms. We thank you for your pastsupport of the LSU AgCenter andrequest your continued support so wecan maintain, and enhance, our quest toimprove the quality of your lives andcommunities.

When individual homeowners try to get rid of the red imported fire ant, allthey really do is move the mounds around their own yard or send them to theneighbor’s.

That’s why Dale Pollet, LSU AgCenter entomologist, is promoting a plan inwhich city dwellers band together by neighborhood to control the spread of thistroublesome pest.

Called “Put the Fire Out,” the plan involves a two-step treatment methodthat costs less and is more effective than when people work alone. The planrequires somebody to take the lead. This can be an existing neighborhoodassociation or some type of committee formed for this purpose. This person orgroup can buy the bait in bulk at far cheaper prices than when purchased in smallquantities.

“It helps if everyone in the neighborhood agrees to cooperate,” Pollet said.The two-step plan involves areawide treatments in the spring and fall

followed by treatments of individual mounds as they arise.“To maintain control, neighborhoods may have to repeat the areawide

treatment yearly,” Pollet said.Here’s how the plan works:

Inform the neighborhood residents of the date for treatment. Be sureto include an alternate date in case of rain.Decide how the bait should be distributed. A central location whereresidents can pick up the bait on the designated date is effective. Blockcaptains also can be used to distribute bait. They can check to see ifeveryone on the block treats.

“Don’t worry if a few residents refuse to participate. Their ants will feed onbait in neighboring yards,” Pollet said.

Distribute the bait according to size of property. Residents will needto provide measurements. If possible or necessary, borrow spreadersthat residents can return when done.Broadcast the bait on all areas of the property, including sidewalks.Treat individual mounds with about 3 to 5 tablespoons of bait.

“More is not better with these baits. Follow the directions,” Pollet said,adding that it is important not to disturb the mound when applying the baitbecause this may cause the ants to move before they eat it.

Rest assured, however, that even the best of plans will not rid Louisiana ofthe red imported fire ant. Rather, the goal is to keep their populations down toeconomically acceptable levels.

“The red imported fire ant is here to stay,” Pollet said.Though a pest, fire ants can be beneficial. They feed on insects including ticks,

fleas and termites. Louisiana sugarcane farmers like that they eat the sugarcaneborer, the No. 1 insect pest of that crop. This can reduce their need for one ortwo pesticide applications.

More information may be obtained on organizing a “Put the Fire Out”campaign by contacting local parish LSU AgCenter extension offices or by visitingthe website: www.lsu.edu/ants. Linda Foster Benedict

LSU AgCenter Urges City Dwellers

Let’s Get Neighborly

To Unite for Fire Ant Control


Linda M. Hooper-Bùi, Assistant Professor,Department of Entomology, LSU AgCenter,Baton Rouge, La.

Fire AntControlin UrbanAreas

This pest’spopulationcontinues to growin Louisiana.However, researchshows numbers canbe held in checkwith a blanketapproach.

Linda M. Hooper-Bùi

ed imported fire ants are ubiqui-tous in Louisiana. They inhabit pastures,fields, playgrounds, lawns, flowerbedsand even potted plants. These ants arecalled imported because they wereaccidentally brought here from SouthAmerica in the early 1930s. In suchcountries as Brazil and Argentina, theants are held in check by other organ-isms and environmental factors. InLouisiana, however, there are no naturalcontrols, resulting in an ever-growingpopulation.

In infested urban areas, red importedfire ants can cause many problems. Ifstung, some people suffer allergicreactions, secondary infections andunsightly skin damage. The ants cancause structural damage in houses andindustrial buildings. Some infestationslead to damage of waste containers,electronic circuitry, ground-placedindustrial lighting and even trafficcontrol lights.

Photos by Mark Claesgens

Residents used hand-held spreaders to apply the bait in their yards. When they returned thespreaders, they indicated on a map where they had spread the bait. Researchers could thenmake sure the entire area was covered.

Fire Ant BiologyRed imported fire ants are omnivo-

rous and opportunistic in their foodgathering. They will gather practicallyanything, including dead animals andplants, and will kill other arthropods.Fire ants can remove seeds, developingand ripe fruit, and feed on sap flows.

Reproduction in fire ant colonies isaccomplished by winged “sexuals.”These winged individuals fly out of thecolony and mate in the air. The malesdie, and the mated females return to theground (often after flying several miles)to find a suitable place to start a nest.

The mating flight is one way fire antsinfest previously noninfested or treatedareas. Another way is by splitting thecolony (budding) or moving the colonyafter it has been disturbed.

The fire ant queens lay eggs thathatch into balloon-like, helpless larvae.Worker ants use these larvae to processthe solid food they gather into a formeasily consumable by the colony. Larvaeeventually transform into adults. Theadult ants function as workers who buildthe nest, feed other workers and larvae,and most important, care for and feed thequeen. The workers that provide the

R


Baton Rouge residents signed up to receive their share of bait. All spread the bait in their own yards all on the same day to blanket theirneighborhood.

colony with food will exit the colony ormound through tunnels and forage forfood on the soil surface.

How Baits WorkBecause of the way worker ants feed

the rest of the colony, baits make anappropriate and effective means ofcontrol. Baits consist of a food itemdesirable to the target ants combinedwith either a slow-acting toxicant or agrowth regulator. The worker ants passthe food around to the various membersof the colony, who will eventuallysuccumb to the effects of the toxicant orbe rendered sterile from the growthregulator. Either way, the population ofaffected ants will die.

Homeowners have used bait foryears, but results are usually short-lived.The baits were probably working andcontrolling the ants in the treated yards,creating an “ant-free zone.” Because oftheir mobility, ant colonies from theneighboring yards may move into areaswhere the baits had not been used.

LSU AgCenter ResearchThe LSU AgCenter began focusing

research efforts on fire ant control inurban areas in 1998. Researchers wantedto test the effectiveness of large-scale,community-based management tech-niques as compared to individualhomeowner efforts. Traditionally, large-scale bait treatments of red imported fire

ants have been applied to agricultural orgrazed fields. The practice of managingfire ants using a large-scale technique inurban areas has been tried in othersouthern states, beginning in Arkansas in1991. Texas made popular a two-steptechnique in which insecticidal bait isbroadcast followed by individual moundtreatments with a contact insecticide.

To study fire ant control in an urbanarea, LSU AgCenter scientists selectedfor the large-scale portion of the study an85-acre subdivision near downtownBaton Rouge called Spanish Town. Ninehomes within the neighborhood wereselected for more intense study of theants, and three nontreated areas adjacentto the subdivision were monitored.


For the small-scale portionof the study, 30 individualhomes scattered in Baton Rougeclose to Louisiana StateUniversity were chosen fortreatment. Three homes wereused as nontreated controls.

Large-scale Studyin Spanish Town

LSU AgCenter personnelworked with Spanish Townresidents to develop the plan,which was nicknamed “Put theFire Out.” The homeownerswere to broadcast bait in theirindividual yards all on the sameday at three times six monthsapart—April 17 and Oct. 16,1999, and April 22, 2000. Theresidents were instructed tomeasure the area of theirproperty and subtract the area oftheir house’s footprint. LSUAgCenter personnel thendistributed the appropriatequantity of bait and a hand-heldspreader to each of thehomeowners on the three days.

Each homeowner receivedone of three baits—Amdro,Distance or Award—randomlyassigned and recorded on a datasheet. The spreader with thecorrect amount of bait was checked outto the individual, who then treated his orher yard. When the resident returned thespreader, he or she was asked to mark ona map the area treated to ensure that theentire area was covered.

LSU AgCenter employees broadcastmonthly each type of bait at three of thenine houses (for three replicates) inconjunction with the community effort.The type of bait each of thestudy houses received wasrandomly assigned butremained the same through-out the study.

Small-scaleTreatment ofIndividual Homes

Thirty homes weretreated with the same threebaits—10 per bait. Using ahand-held spreader, a pestcontrol technician applied allof the broadcast bait treat-ments to the 30 houses. Thisensured that the bait wasspread correctly and consis-tently. The individual homes

This line chart follows the average number of mounds inyards in Baton Rouge’s Spanish Town neighborhoodafter large-scale treatments. Treatments were appliedin April and October of 1999 and April of 2000. Area-wide broadcast treatments with baits maintained fireant mound reduction for six months after application.

areas set for treatment and thenontreated controls. After theinitial treatment, the moundswere counted monthly in eachhomeowner’s yard and thenontreated control areas. All three baits used weresuccessful in reducing thenumber of fire ant mounds inall homeowners’ yards in thestudy. Large-scale fire antcontrol using baits was moreefficacious than individualhomeowner efforts. Small-scale treatments initially wereeffective with a reduction infire ant mounds for the firstmonth and then graduallyincreased, supporting thehypothesis that the fire antswere moving from the neigh-bors’ yards. Results from thelarge-scale application demon-strate that granular baits areeffective in controlling redimported fire ants. Antmovement from nontreatedadjacent areas into the treatedarea thwarted the small-scaleefforts. Because baits offerlittle or no residual, there is noprotection from re-invasionfrom neighboring nontreatedareas. This LSU AgCenter study

demonstrated that large-scale treatmentin urban areas may slow the re-invasionof red imported fire ants and reduce thenumber of treatments needed, cost oftreatments and the amount of chemicalsreleased in the urban environment.Treatment for fire ants with the large-scale broadcast approach, in which baitis bought in bulk, would have cost each

resident of Spanish Townabout $2 to $10 per year alltogether, depending on thesize of their yards. (Forparticipating in the study,residents received the baitfree.) This is compared to anestimated $20 to $100 eachhomeowner would have to payper year to treat for redimported fire ants on his orher own. With large-scale fireant treatments using broadcastgranular baits, residents canexpect to reduce ant controlcosts tenfold, reduce fire antpopulations and experiencemore success.

were treated in April 1999. However,this treatment method was not aseffective as the areawide treatment.

Numbers Go DownBefore the initiation of the study,

mounds were counted in the yards of the

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“Put the Fire Out” is the name of the LSU AgCenter programthat helps communities band together to help control fire antpopulations.

Illustration by Elma Sue McCallum


ormosan subterranean termiteshave proved to be one of the mostformidable pests ever to invade Louisi-ana. Their success is a numbers game.Compared to a native Louisiana subterra-nean termite colony of up to one millionindividuals, Formosan subterraneantermite colonies can have 10 millionindividuals. One colony in Algiers, La.,had an estimated 70 million individuals.

Big numbers cause big problems.The Formosan subterranean termitecauses severe economic loss, includingan estimated $300 million of propertydamage per year in New Orleans alone.For example, termite damage caused onehouse to split apart and required thatseveral other houses and an apartmentcomplex be demolished. People aredefaulting on mortgages and cannot getloans to repair their damaged homes.

The Formosan subterranean termiteis aggressive in its pursuit of water. Itfinds sources of water other than groundmoisture, such as leaking pipes, roofleaks and blocked gutters. It builds nestsabove ground in walls, which can storewater for future use. This frees thetermites from the continuous groundcontact that subterranean termitesrequire. Formosan subterranean termitescan eat the untreated centers of creosote-treated railroad ties, pilings and utilitypoles. They will go through thin sheetsof soft metal, mortar, gypsum board,

PVC pipe, electric power lines andtelecommunications lines to reach foodand moisture sources. They can also gothrough 1/16-inch cracks in concrete,entering homes without requiring typicalmud tubes. Once in the interior they cankeep out of sight while doing majordamage to interior walls.

LSU AgCenter researchers havebeen tracking numbers of the Formosansubterranean termites since 1989 andhave found a continual increase, exceptfor slight downturns in 1997 and 2000(Figure 1).

Unlike our native subterraneantermites, the Formosan subterraneantermite infests the wood of live trees.This not only provides them a foodsource but also serves as a reservoir forinfestations into nearby structures.Weakened trees are susceptible to beingblown over in high winds.

The LSU AgCenter is taking athree-pronged approach to find solutionsto the Formosan subterranean termite

problem. One is entomological andinvolves study of the insect and ways tocontrol its numbers. Another is amaterial properties approach to deter-mine the best way to protect existing andfuture structures from attack. The third iseducation.

LSU AgCenter entomologistsstarted studying the insect when it wasfirst identified in Louisiana in 1966.Termite bait research started at the LSUAgCenter in 1991. This work resulted indevelopment of bait systems now on themarket.

Another control method beingexplored is a plant extract callednootkatone from vetiver grass roots.Nootkatone has been used in theperfume industry and for flavoring incitrus drinks. It has been found to act asa repellent with the Formosan subterra-nean termite.

In reducing termite populations,research efforts have been focused ontargeting termites in living trees. One

Figure 1. LSU AgCenter researchers have been tracking numbers of theFormosan subterranean termites since 1989 and have found a continualincrease, except for slight downturns in 1997 and 2000.

W. Ramsay Smith, Program Leader andProfessor, Louisiana Forest Products Labora-tory; Dennis R. Ring, Associate ExtensionSpecialist; Gregg Henderson, AssociateProfessor, Department of Entomology; QinglinWu, Associate Professor, and Todd F. Shupe,Assistant Professor, Louisiana Forest ProductsLaboratory; and Michael A. Dunn, ProgramLeader and Assistant Specialist – ForestryExtension Natural Resources, LSU AgCenter,Baton Rouge, La.

Formosan SubterraneanTermites in Louisiana

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They are here to stay. But, the LSU AgCenter is takinga three-pronged approach to stem their spread.

W. Ramsay Smith, Dennis R. Ring, Gregg Henderson,Qinglin Wu and Michael A. Dunn



implementation of this research is a five-year, $5 million treatment project startedin New Orleans in the spring of 2000.The project involves treating trees and isdirected by the Louisiana Department ofAgriculture and Forestry. LSU AgCenterscientists are involved in the evaluationof the project.

Another avenue for reducing theproblem is to reduce the spread of thistermite. Used railroad ties sold aslandscape timbers are common means oftransport. As a result of education effortsby LSU AgCenter researchers andcollaborators from other institutions, theRailway Tie Association and NorfolkSouthern Corporation instituted strictguidelines for movement of railroad tiesas of December 11, 2000. In addition,they have organized an industry effort todetermine the scope of the problem andwork toward the necessary solutions toend the spread of Formosan subterraneantermites through this route.

The Louisiana Forest ProductsLaboratory is addressing the problem byworking to develop and test woodtreatments that will protect structuralmaterials from attack. There are chemi-cals and treated wood on the market thatresist termite attack. Most chemicals,however, are primarily used on solidwood components such as sill plates,studs and plywood. Few are suitable forengineered wood products such asoriented strandboard or wood-based I-beams. These chemicals use water totransport them into the wood, whichaffects swelling properties and hencedimensional change and strength whenapplied after manufacturing. They canalso affect the gluing characteristics ofwood particles before manufacturingbecause of resin-additive interactions.For a treatment to work, it has to beeffective against the termite withoutcompromising the product propertiesduring service. Research, therefore, isbeing carried out to determine andenhance physical properties and efficacyof various treatments for engineeredwood products.

Adequate protection for residentialstructures requires education of thepublic. An integrated program includesusing the proper techniques and under-standing the interactions betweenplanning, designing, site preparation,building and long-term maintenanceduring the life of a structure. The LSUAgCenter has educational programs forhomebuilders, homeowners and pestcontrol operators.

In an effort to help pest controlThis tree was so weakened from termite infestation that high winds blew it onto this housein New Orleans.

The Louisiana Forest Products Laboratory is testing wood treatments that will protectstructural materials from termites. This house in New Orleans is being constructed withborate-treated lumber. Borates have been found to be toxic to termites.

operators address site preparation andpest management techniques, the LSUAgCenter coordinates a two-day termitetraining school twice a year for them.Approximately 150 operators are trainedper year. In addition, a six-day course isoffered at the LSU Summer Urban PestManagement Institute that includeseducational programs on integrated pestmanagement of most types of urbanpests. This institute produces about 30graduates per summer.

Photo by W. Ramsay Smith

Photo by Gregg Henderson

The Formosan subterranean termiteis here to stay. It is well established inthe southern United States and is beingspread primarily by humans. Its ability toinfest living trees will help assure itscontinued existence. The only hope ofmanagement and control is througheducational and research efforts, such asthose being conducted by LSU AgCenterscientists in cooperation with otheragencies and institutions, including theLouisiana Department of Agriculture andForestry.



nsects, such as the Formosansubterranean termite, are cold-bloodedanimals that depend on temperature andweather conditions for normal function-ing. Temperature, humidity, rainfall,wind and even electrical charging in theair can affect termite behavior. Under-standing how the weather affectsFormosan subterranean termites maylead to improvements in ways tomanage them.

During cold months, social insectslike subterranean termites and ants gointo a quiescent state, huddling togetheruntil warmer weather allows them tosearch again for food. Foraging byFormosan subterranean termites isstrongly influenced by temperature.Louisiana’s steamy, subtropical climateis a big reason such a massive popula-tion of this invasive insect pest liveshere. Termites can forage for food mostof the year in Louisiana.

The annual swarm season of thewinged reproductives (alates) also isinfluenced by temperature and moisture.In Louisiana, May is warm, humid andthe air is electrically charged because offrequent late-afternoon thunderstorms.These conditions allow the Formosansubterranean termites to start theirmating flights around Mother’s Dayeach year.

Termites exert some control overtheir own environment, especially inregulating nest temperatures. The termitenest is a well-constructed labyrinth ofgalleries and pathways surrounded by ahardened shell made from their ownexcrement, glandular secretions andtransported clay particles. Nest tempera-tures in a Formosan subterranean termitecolony stay fairly constant (91 degreesF) for all but the coldest months as aresult of heat generated by the metabo-lism of millions of tiny termite bodies,aided by the even tinier dung-lovingfungi that cohabit the nest.

Formosan subterranean termites,unlike most subterranean termite species,will build nests above and below ground.In Louisiana, aboveground nests areoften found in attics and walls neardoorways and window frames and in thecenter of living trees that the termiteshave consumed. Again, weather mayplay a role in this “small-minded” (atermite brain is the size of a grain ofsand) but wise decision.

Subterranean termites often areexposed for long periods to inundationfrom rainfall that can accumulate intopuddles on top of the soil for days. Tostudy how subterranean termites react toand are affected by rising water levels,we took Formosan subterranean termites,along with their more commonly foundcousins, the eastern subterranean termiteand the southern subterranean termite,and completely submerged them in waterin a laboratory setting. Besides giving usclues as to how heavy rainfall mightaffect a ground-nesting termite colony,the results of this study gave us insighton termite movement along waterways.We wanted to determine, for example,how likely a new infestation might occuras a result of a termite-infested tree limbbreaking during a storm and travelingacross a lake or down a river to fertile,cellulose-rich environs.

Our study indicated that subterra-nean termites escape drowning whenconfronted with excessive amounts of

Termites Under the WeatherGregg Henderson

subterranean species to drowning, thatsuggests they have a possible survivalstrategy for building aboveground neststhat has evolved over millions of years.Termites have been on this earth formore than 200 million years. Unwit-tingly, this nest construction behavioralso helps Formosan subterraneantermites bypass traditional liquid groundbarrier treatments applied commonly bypest control operators today, since thistreatment does little to affect anaboveground colony.

Although too much water can kill atermite colony, water is necessary fortheir survival and termites will activelyseek it. Formosan subterranean termiteswill even transport water from belowground to aboveground sites. If water isnot constantly available to the colony,the soft bodies of subterranean termiteswill quickly dry out. For this reason, aleaking roof that causes moisture buildupin the walls of a house will make a pestcontrol operator hesitant to provide atreatment warranty. Pest control profes-sionals know of the termite’s attractionto these moist areas.

Such aboveground nest constructionhas led to the misconception thatFormosan subterranean termites willstart a new colony in an abovegroundlocation, like the walls of a house. Thisis not likely. A study we conductedevaluated the likelihood of a colonygetting its start in a normally dry wall.Given the choice between a moistlocation and a dry location to start a newcolony, the new queens and kings almostalways chose the moist site. The termiteschoosing the dry site would have soondied. The drastic drop in termite num-bers observed in our 2000 census mayhave had something to do with thedrought of 1999, making it harder foraboveground colonies to survive. SeeFigure 1 on page 9.

Knowing the moisture-loving habitsof Formosan subterranean termites canhelp in their management. To find whattermites consider the most favorableconditions in which to live, we con-ducted a 13-month study around a

Gregg Henderson, Associate Professor,Department of Entomology, LSU AgCenter,Baton Rouge, La.

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water not by seeking higher ground, ascommonly observed in red imported fireants, but by entering an immobile statethat conserves oxygen. In this suspendedstate, it took 30 hours of submergencefor 90 percent of the eastern subterra-nean termites to drown, 23 hours forsouthern subterranean termites and 16hours for Formosan subterraneantermites. That is a long time for anyanimal to hold its breath! Of course, anatural soil profile or a log floating downa river would have air pockets. The timebefore drowning would likely take evenlonger. Such a natural event has beendocumented. In 1992, an areawide floodin west central Georgia that saturated thesoil for more than a month resulted in a77 percent reduction in subterraneantermite populations.

Because Formosan subterraneantermites are the most susceptible

Formosan subterraneantermites, unlike mostsubterranean termitespecies, will build nestsabove and below ground.


termite-infested apartment complex inNew Orleans. Since moist soil conditionsare believed to be one of the mostimportant conditions, wooden stakeswere placed near locations like drippingfaucets, air conditioning units, areashaving improper drainage and wooddebris that helped retain moisture, with asimilar number of wooden stakes placedin areas not appearing so attractive. Fourseparate inspections of 426 stakes placedaround the apartment complex showedthat moister sites had an almost 2 to 1difference in attacks. With the advent oftermite baits available in today’s termitecontrol marketplace, this fact can beparticularly important. The moreattractive to termites the baits can bemade, the greater the impact they willhave on reducing termite populations.

We tested this idea of “precisiontargeting” in the baiting of termites.About 1,200 cardboard monitors were

AcknowledgmentU.S. Department of Agriculture AgriculturalResearch Service Southern RegionalLaboratory-New Orleans and the LouisianaDepartment of Agriculture and Forestry

Swimming pool experts advised on how to anchor theunderground containment to keep it from pushing out of theground during heavy rains.

To study the foraging behavior of soil-dwelling ter-mites, LSU AgCenter scientists were involved in the buildingof a termitarium in New Orleans on the site of one of thefacilities of the Mosquito and Termite Control Board. Atermitarium is a large underground nesting chamber with apair of sandwiched Plexiglas sheets for viewing two captivetermite colonies while they forage both below and aboveground. Being in contact with the soil, the termites placedin the large “farm” faced the natural fluctuations of soiltemperature and moisture. A fine mesh stainless steelscreen kept the termites contained inside in contact withthe soil. Inside the aboveground portion of the termitariumwas pine framing, which served as an attractive place for nestconstruction for Formosan termites. A roof constructedabove the termitarium kept the unit from becoming too hot.Two times each day for a year, air and soil temperatures andobservations of foraging were recorded. Abovegroundforaging was found to be closely associated with ambient airtemperatures.

Termitarium RevealsTermite Habits

Photos by Gregg Henderson

The termites could be viewed from the top. The termitarium islocated at one of the facilities of the Mosquito and TermiteControl Board in New Orleans.

Gregg Henderson, Associate Professor, Department ofEntomology, LSU AgCenter, Baton Rouge, La.

placed around 16 public schools inOrleans, Jefferson and St. Bernardparishes and examined each month formore than two years for attacks bytermites (hits) before and after treat-ments. We were particularly interested inknowing how soil temperature andmoisture affect hits by termites. Termiteattacks on monitors fluctuated with theseasonal changes in temperature, withwinter showing the lowest “successrate.” We also found that Formosansubterranean termites and nativesubterranean termites prefer different sunexposures. Formosan subterraneantermites showed a strong preference foreast and north exposures, whereas nativesubterranean termites were not so pickybut seemed to like southern exposuresthe most. Soils on the east and northsides of a building retained moremoisture and did not dry out or stay ashot. Monthly soil temperature readings at

4-inch depths verified that sun-exposedlocations were warmer. Native subterra-nean termites may have selected south-ern exposures more often because theywere farther away from the largepopulations of the more aggressiveFormosan termite.

The more we know how the weatheraffects termite behavior and biology, themore likely we can develop improvedmethods to control them. Now if wecould just understand the weather! Tolearn more about how termites get intoyour home and what you can do aboutthem, you may visit our websitewww.agctr.lsu.edu/wwwac/termites.



Rural Land Valuesat the Urban FringeRural land value contours were estimatedto show the combined effects of locationand economic development. In general,the metropolitan areas of Baton Rougeand New Orleans have a dramatic effecton rural land values.

Lonnie R. Vandeveer, Steven A. Henning, Huizhen Niu and Gary A. Kennedy

Figure 1. The study area includes the metropolitan statistical areas of New Orleans and Baton Rouge. Eachsymbol represents the location of each of the 237 rural land sales from 1993 to 1997. Data indicate a clusteringof relatively higher per acre sales in a commuting area north of New Orleans and another clustering of suchsales north of Baton Rouge.

Lonnie R. Vandeveer, Warner L. Bruner Regents Professor; Steven A.Henning, Associate Professor; Huizhen Niu, Instructor/GIS Manager; andGary A. Kennedy, Adjunct Associate Professor, Department of AgriculturalEconomics and Agribusiness, LSU AgCenter, Baton Rouge, La. Kennedy isalso Associate Professor, Agricultural Sciences Department, LouisianaTech University, Ruston, La.

growing population with added economic activity inurban areas influences rural land markets at the rural-urbanfringe. With more rural land acres being converted at the urbanfringe, buyers, sellers, planners, appraisers, tax assessors,lenders and others are expected to have an increasing need forinformation about the effect of location and economic develop-ment on rural land values.

Research results from a spatial econometric study of therural land market in southeast Louisiana provide an indicationof the factors that influence rural land values in this area and

A


the magnitude of these factors in this market. Factors studiedinclude site characteristics, tract location and economicdevelopment activity.

Site characteristics hypothesized to influence per acre ruralland values in this analysis are size of tract and the dollar valueof improvements. The size of tract is expected to have anegative relationship with per acre selling price because fewerbuyers compete in markets for larger tracts and many buyerscompete in markets for smaller tracts. Value of improvementsis expected to have a positive influence on per acre values.

Three hypothesized relationships are included as measuresof location and economic development. These include traveltime to nearest city, distance to nearest town and paved accessroad. The travel time and distance variables are expected tohave a negative influence on per acre rural land values.Location theory generally suggests an inverse relationshipbetween distance to markets and per acre selling prices. Pavedroad access is expected to reflect development potential andaccessibility and have a positive influence on per land values.

The effects of economic development and other factors aremeasured by four variables. These variables include location inthe New Orleans metropolitan statistical area, commercialreason for purchase, recreational reason for purchase andmonth of sale. Location in the New Orleans metropolitanstatistical area and month of sale are expected to have apositive influence on per acre values, and a recreational reasonfor purchase is expected to have a negative influence on landvalues. The location of a tract in a metropolitan statistical areais expected to be influenced by economic development.

Data for this study are based on rural land market salesfrom southeast Louisiana as determined through a mail survey.The rural land market survey was mailed to state certifiedappraisers, officers in commercial banks, Farm Service Agencypersonnel, Federal Land Bank personnel, Production CreditAssociation personnel, members of the Louisiana Chapter ofthe American Society of Farm Managers and Rural Appraisers,and members of the Louisiana Realtors Land Institute. Eachrespondent was asked to provide rural land sales of 10 acres ormore in size including attachments to the surface such asbuildings and other improvements and sales outside theboundaries of towns and cities.

The study area includes the metropolitan statistical areasof New Orleans and Baton Rouge. Each symbol in Figure 1represents the location of each of the 237 rural land sales from1993 to 1997. Data indicate a clustering of relatively higher peracre sales in a commuting area north of New Orleans andanother clustering of such sales north of Baton Rouge.

Marginal implicit prices presented in Figures 2 and 3 areused to observe the magnitude and direction of influence ofvarious factors on per acre land values. For convenience,marginal implicit prices are evaluated at mean values of peracre price and of the characteristic. A positive marginalimplicit price suggests that an increase in that characteristicresults in an increase in the per acre price of rural land, otherthings constant. Conversely, a negative marginal implicit priceresulting from a negative coefficient has a depressing effect onper acre land prices.

Marginal implicit prices for continuous model variablesindicated that both the value of improvements and time of salehave a positive influence on per acre land value (Figure 2). A$1,000 increase in improvements increases per acre value by$4.24. Similarly, the time of sale estimate indicates that,starting in 1993, each additional month adds $18.93 to the peracre value of a tract of land.

Figure 3. A tract located in the New Orleans MSAsells for $1,758 more per acre than a tract notlocated in this MSA, and a tract purchased forcommercial purposes (COM) sells for $979 moreper acre than other tracts. A tract with pavedroad access (RT) sells for $421 more per acrethan a tract that does not have paved road access.Land purchased for recreational purposes (REC),however, sells for $379 less per acre than a tractpurchased for other reasons.

Figure 2. A $1,000 increase in improvementsincreases per acre value (VALUE) by $4.24.Similarly, the time of sale estimate (TIME)indicates that, starting in 1993, each additionalmonth adds $18.93 to the per acre value of a tractof land. A one-acre increase in size (SIZE),however, decreases per acre price by $4.19. Thedistance to nearest town variable (DNT) indicatesthat a one-mile increase from the nearest towndecreases per acre value by $17.87; the traveltime variable (TTNC) indicates that for eachminute increase in travel time from nearest city(Baton Rouge or New Orleans) per acre landvalue decreases $17.30.

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Figure 4. Results indicate that the effects of location and economic development cause land values to vary from$500 to $4,000 per acre in this area. Rural land values vary from $3,700 per acre for areas close to Baton Rougeto $500 per acre as distance increases from Baton Rouge.

Three continuous variables were estimated to have anegative influence on per acre values. A one-acre increase insize decreases per acre price by $4.19. The distance to nearesttown variable indicates that a one-mile increase from thenearest town decreases per acre value by $17.87, while thetravel time variable indicates that, for each minute increase intravel time from the nearest city (Baton Rouge or New Or-leans), per acre land value decreases $17.30.

Implicit marginal prices for discrete model variablessuggest that a tract located in the New Orleans metropolitanstatistical area sells for $1,758 more per acre than a tract notlocated in this area; a tract purchased for commercial purposessells for $979 more per acre than other tracts (Figure 3).Similarly, the marginal implicit price suggests that a tract withpaved road access sells for $421 more per acre than a tract thatdoes not have this access. Land purchased for recreationalpurposes sells for $379 less per acre than a tract purchased forother reasons. This generally reflects marginal land purchasesthat are primarily suitable for hunting and fishing.

Land Value ContoursRural land value estimates from the spatial econometric

model along with Geographic Information Systems (GIS)

procedures are used to estimate rural land value contours,which reflect effects of location and economic development onper acre rural land values (Figure 4). Similar to topographicmaps that show equal elevation above sea level, the Louisianaland value contour map depicts areas with approximately equalper acre land values. In this analysis, tract size, improvementvalue and time variables are held constant in developingpredictions, while travel time to nearest city, distance to nearestcity, paved road access, New Orleans metropolitan statisticalarea, commercial reason for purchase and recreational reasonfor purchase variables were allowed to vary.

Results presented in Figure 4 illustrate the effects of NewOrleans and Baton Rouge metropolitan areas on per acre ruralland values. St. Tammany Parish, directly north of NewOrleans, is in the New Orleans metropolitan statistical area.This parish also is connected to the New Orleans area via thePontchartrain Causeway. Results indicate that the effects oflocation and economic development cause land values to varyfrom $500 to $4,000 per acre in this area. In Figure 4, ruralland values vary from $3,700 per acre for areas close to BatonRouge to $500 per acre as distance increases from BatonRouge.


WATER QUALITY

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Figure 1. Watershed Study

For the watershed study, water samples werecollected at 10 points along the station’s naturaldrainage after rainfall events. These points includeddrainage from a 300-acre wooded area containing nolivestock and drainage from grazed pastures. Typicalresults from five of the sites, including two with nolivestock and three with livestock after two randomrainfalls, are shown above. Fecal coliform counts insurface runoff from timberland with no livestockfrequently exceeded the primary standard forswimming and other contact recreation. Fecalcoliform counts in surface runoff from grazedpastures routinely exceeded the primary standard bya factor of 10 or more.

Caye M. Drapcho, Assistant Professor, Biologicaland Agricultural Engineering; James F. Beatty,Professor and Resident Director, SoutheastResearch Station, Franklinton, La.; and Eric C.Achberger, Associate Professor, BiologicalSciences, LSU AgCenter, Baton Rouge, La.

major water quality concern inLouisiana is the concentration of fecalcoliform bacteria in our streams andbayous. Currently four health advisoriesthat limit primary contact recreation suchas swimming are in place because ofelevated fecal coliform counts. Theseadvisories are for the south shorebeaches of Lake Pontchartrain, 18 milesof the Tchefuncte River, 12 miles of theBogue Falaya and 79 miles of theTangipahoa River. The LouisianaDepartment of Environmental Qualityidentified three potential sources of fecalcoliform contamination in theTangipahoa River: leakage from faultyhome septic systems, effluent frommunicipal wastewater treatment plantsnot operating properly and runoff fromconfinement areas of dairy farms wherecattle are held for feeding. Dairy farmsin the watershed were required toinstall waste treatment lagoons andapply the water from the lagoons tonearby pastures to prevent transport offecal coliform bacteria to nearbysurface waters.

Fecal coliform bacteria are foundnaturally in the intestinal tract of warm-blooded animals. Average fecal coliformcounts per gram of waste vary from230,000 for cattle to 13 million forhumans. Escherichia coli is the predomi-nant fecal coliform in the waste of mostwarm-blooded animals. The percentageof the fecal coliform count in animalwaste attributed to E. coli ranges from 84percent for pigs, 97 percent for sheepand humans, and 99.9 percent for cows.Although fecal coliform bacteria as agroup are not pathogenic, they are usedas a test of recent fecal contaminationfrom either animal or human origin;

however, the fecal coliform test as anindicator of water contamination insubtropical and tropical climates hasbeen questioned. This is because thepresence of some soil bacteria fromnonfecal sources may show up as “falsepositives.”

A research project was initiated atthe LSU AgCenter Southeast ResearchStation in Washington Parish to evaluatethe effect of dairy farming on surfacewater quality. The objectives were toquantify the fecal coliform content insurface water runoff from grazedpastures as compared to drainage fromnongrazed pastures and forested areasand to determine if bacteria fromnonfecal sources were contributing asignificant portion to the fecal coliformcount. The research consistedof a watershed study and afield-scale study.

The dairy farm at theSoutheast Research Station isa fairly typical size forLouisiana, with a dairy herdof 180 milking cows. As withmost Louisiana dairy farms,the cows are fed forage inconfinement systems about25 percent of the time andgraze on pastures the rest ofthe time. Waste from confine-ment areas is collected andtreated in a lagoon system.Dairy cattle are grazed at anaverage density of one cowper acre.

For the watershed study,water samples were collectedat 10 points along the naturaldrainage at the station afterrainfall. These pointsincluded drainage from a300-acre wooded areacontaining no livestock anddrainage from grazedpastures.

For the field-scale study,plots with water collection

troughs were installed in Bermudagrasspastures. Dairy manure was appliedevenly over the surface of four of theplots; no manure was applied to the otherfour plots. During periods of drought, adevice called a rainfall simulator wasused to water the plots. Runoff waterwas collected to determine the fecalcoliform count and the percentage of thefecal coliform count caused by E. coli.This information can help determine ifthe fecal coliform bacteria in a watersample originated from dairy cattle oranother animal source. No attempt wasmade in this study to find pathogenicstrains of E. coli, such as O157:H7.These strains would be expected toaccount for less than 0.5 percent of thetotal E. coli count.

Research shows that woodlands and dairy farm pastures both contribute tocontamination. Better systems for measuring fecal coliform numbers are

needed in Louisiana’s warm, subtropical climate.

Caye M. Drapcho, James F. Beatty and Eric C. AchbergerA

and the Tangipahoa River



Results from the watershed studyindicate that the fecal coliform levels insurface runoff from timberland with nolivestock frequently exceeded thestandard set by LDEQ for swimming andother primary contact recreation. Fecalcoliform counts in surface runoff fromgrazed pastures routinely exceeded theprimary standard by a factor of 10 ormore (Figure 1). The values increased asthe water flowed along the drainagethrough the station. Fecal coliformcounts at the last sampling location weresimilar to levels in the liquid portion ofthe lagoon.

For the field-scale study, the fecalcoliform counts in the surface runofffrom the pasture plots that receivedmanure were 10 to 30 times higher thanthe primary standard when collected oneday after manure application. Fecalcoliform colonies in these samplesincluded at least 90 percent E. coli. Forrainfall applied one and two weeks aftermanure application, the fecal coliformcount in the surface runoff declined tonear the standard set for primary contactrecreation. This is caused by decay of thebacteria and physical removal of thebacteria from the soil surface. E. coliaccounted for only 10 percent to 50percent of the fecal coliform count.

For the nontreated plots, the fecalcoliform count in the surface runoffsamples was not zero as might beexpected. Rather, the fecal coliformcount was near the primary standard formost periods of rainfall and did notdecline with time. For rainfall appliedone and two weeks after the beginning ofthe study, fecal coliform counts in therunoff from the manure-applied plotsand the nontreated plots were essentiallythe same. Further, fewer than 5 percent ofthe fecal coliform colonies in the runofffrom the nontreated plots were E. coli. The information obtained fromthese studies suggests that bacteria fromsources other than dairy cattle maycontribute a substantial portion of thefecal coliform count. The fecal coliformcounts from the forested area containingno livestock in the watershed studyindicate that wildlife contribute fecalcoliform bacteria to water. In addition,the data from the control plots in thefield-scale study indicate that soilbacteria may be causing “false positive”readings on the fecal coliform test.Although the fecal coliform test uses anelevated incubation temperature toprevent the growth of nonfecal bacteria,researchers have shown that soilcoliforms from the Klebsiella and

Citrobacter groups are able to grow atthe high incubation temperature.

This study also suggests thatgrazing cattle may represent a signifi-cant source of fecal coliform contamina-tion to surface waters. The fecalcoliform counts from the grazed pasturesin the watershed study and from themanure-applied pasture plots in thefield-scale study were above the primarystandard, and most of the fecal coliformcount was caused by E. coli. Furtherresearch on management measures andgrazing practices that could reduce fecalcoliform transport from grazed pasturesis needed to ensure that grazing ismaintained as a viable option forLouisiana cattle farmers.

Two problems that limit thedevelopment of effective and sensiblecontrol measures are: (1) distinguishingsoil coliform bacteria from true fecal

coliform bacteria so that accurateassessments of the level of fecal con-tamination are made and (2) identifyingthe source of fecal coliform contamina-tion by differentiating coliforms fromcattle and those from other sources, suchas humans, wildlife and pets.

We are studying the feasibility ofusing DNA fingerprinting techniques tocorrelate specific strains of E. coli toeach common source of fecal contamina-tion. This approach will require develop-ing a database of DNA patternsattributed to E. coli strains from humanand animal sources. In practice, E. coliisolated from water samples would befingerprinted and compared with thedatabase to identify the likely source ofcontamination. Once the source wasidentified, appropriate control ortreatment methods could be used.

Photo by John Wozniak



ost people arefamiliar with the use offorensic entomology in theinvestigation of crimesinvolving humans. However,another area in which thistype of science is valuable isin the investigation ofsuspicious deaths of animalsand suspected cases of animalpoaching. The illegal take ofwildlife is a serious offense.About 16,000 poaching casesoccur annually in Louisiana.Only half of these cases areprosecuted because of limitedor no evidence available.

Traditional techniquesfor establishing time of deathof wildlife are limiting. Atmost, they are effective foronly 72 hours postmortem.These methods includemeasuring the presence ofelectrical currents in muscletissue, which is generally notdetectable after three hourspostmortem. Another methodis comparing the rate ofdecreasing internal tempera-ture to ambient temperature;however, internal bodytemperature is of no valuebeyond 48 hours when carcass andambient temperatures reach equilibrium.A third method involves measuring thedegree of rigor mortis, or stiffening ofmuscle joints. Rigor mortis occurs soonafter death in a predictable manner and islater reversed by internal chemicalchanges. The entire process of stiffening

and relaxing of a carcass takes placewithin the first two days. A fourthmethod measures the physical changesof the eye, including pupil size anddegree of transparency and lumines-cence, but this is no longer of value byDay 3 because of decomposition orconsumption by fly larvae.

The use of insects can furthersupport the estimated postmorteminterval established by these methods forthe first 72 hours. Insects are, however,the primary means of determining timeof death for wildlife recovered three ormore days postmortem. To help develop

an entomological database applicable tofuture poaching cases, a cooperativeresearch effort between the LSUAgCenter and the Louisiana Departmentof Wildlife and Fisheries was establishedin 1999. The purpose of the research isto document succession patterns andspecies composition of necrophilousinsects (carrion-frequenting insects)associated with the Louisiana black bear,whitetail deer and alligator.

Blowflies and BeetlesDecomposing remains of humans

and wildlife provide a food source for

Because the Louisiana black bear is a threatened species, researchers could collect data only from bearsfound dead, usually because of a highway accident. Erin J. Watson is shown with a Louisiana black bearon Day 2 of the study conducted in the spring of 1999.

Erin J. Watson is a Ph.D. candidate in theDepartment of Entomology, LSU AgCenter,Baton Rouge, La.

Photo by C. Lamar Meek

M

Insects Incriminate Poachersof Louisiana WildlifeBecause of LSU AgCenter forensic entomologyresearch, law enforcement officials expect to solve up to1,000 more cases per year.

Erin J. Watson


necrophilous insects. The insects offorensic importance are flies, specificallyblowflies, and beetles. Adult flies arereferred to as the “first wave” of insectsbecause of their ability to locate a freshcorpse within minutes of death anddeposit eggs. These eggs and the flylarvae that emerge serve as a startingpoint for determining the minimal timeelapsed since death. Shortly after thecolonization of the carcass by flylarvae, the “second wave” of insectsarrives. These include predatory andscavenging beetles.

All necrophilous insects recoveredfrom decaying remains display apredictable pattern of association,depending on time elapsed since death,degree of decomposition and seasonalconditions. Entomologists can helpestablish time of death by combiningthese observed predictable “waves”with their understanding of develop-ment rates and life cycles of carrion-frequenting insects.

Blowfly life cycles have beenthoroughly documented by the MedicalEntomology Laboratory of the LSUAgCenter and generally take 11 to 12days for completion (egg, larvae, pupae,adult), except during cool winterconditions. Therefore, postmortemindicators established within the first twoweeks of decomposition typicallyprovide precise estimates of time ofdeath for the south-central United States.Insects still provide valuable cluesbeyond this time period, although thelevel of confidence declines as decompo-sition progresses from advanced toputrid and finally to dry remains.

Data were collected for the forensicentomology research conducted by theLSU AgCenter over the course of threeseasons – spring and fall of 1999 andwinter of 2000. Each seasonal experi-ment consisted of one Louisiana blackbear, two whitetail deer, two alligatorsand two swine (experimental control).Fresh carcasses were randomly assignedto seven sites approximately 300 yardsapart within a forested wildlife preservein East Baton Rouge Parish.

Louisiana Black BearBecause of its status as a threatened

species, the Louisiana black bear cannotbe terminated for experimental purposes.Deceased bears were donated as theybecame available, such as being struckby a vehicle. The size and age of bearsdonated ranged from an 11-year-old,325-pound male to a 5-year-old, 150-pound male.

Whitetail deer were harvested bywildlife officers and generally weighed70 to 90 pounds for each study. Juvenilealligators also were donated by theDepartment of Wildlife and Fisheriesand ranged from 3 to 5½ feet in length.The swine carcasses were donated by theLSU AgCenter and weighed between 60and 100 pounds.

All carcasses were monitoredsimultaneously for necrophilous insectsby three sampling methods: aerial sweepnet, pitfall traps for continuous surveil-lance and manual sampling of thecarcass and surrounding soil. Samplingefforts were terminated at varyingintervals, depending on the length oftime required for each wildlife species toskeletonize. In the spring of 1999, thismeant 24 days for the alligator, 68 daysfor the whitetail deer and 92 days for theblack bear.

Results of the three seasonal studiescan be broken down into severalcategories. First, the duration of insectactivity associated with a carcass directlycorresponded to carcass size. Similarly,the larger the carcass, the longer it tookto skeletonize. For example, the 325-pound black bear in the spring series wasable to support considerably moreblowfly larvae. As a result, larvae werecollected from Day 2 until Day 22postmortem; no larvae were observed atthe alligator, pig or deer after Days 9, 10and 11, respectively.

Second, egg-laying blowfliesshowed no preferential selection oravoidance of wildlife species, but adelayed presence of eggs was noted onalligators due to limited viable sites foregg deposition. As a rule, femaleblowflies will first deposit eggs withinnatural openings and bodily wounds.Alligators were less attractive becausethey had no external wounds, the analregion is virtually inaccessible, and theeyes, nostrils and jaws were shut tight.Because the duration of rigor mortisvaries with temperature, the presence ofeggs and young larvae on alligatorcarrion varied from half a day to a fewdays later than on all other carcass types.

Third, the abundance of insectsassociated with carrion later intodecomposition varied, depending on thewildlife species. The most obviousexample was the lack of scavengingbeetles on alligator carrion duringadvanced decay stages. These scaveng-ing beetles and their larvae feed on driedtissue, including hair and skin. Theirscarcity on alligator carrion was prob-ably due to the absence of fur.

Fourth, overall insect diversity andspecies composition were noticeably lesson alligator carrion than bear, deer orswine. Fifth, there was a dramatic delayof all insect development rates andpatterns because of extremely lowtemperatures in the winter of 2000.Finally, indicator blowfly species andoverall necrophilous species compositionand life stage patterns differed for eachseason.

Solving CasesBecause of LSU AgCenter research,

officials with the Department of Wildlifeand Fisheries anticipate that law enforce-ment officers will be able to solve up to1,000 additional cases per year. Depend-ing on court discretion, convictedpoachers of deer or alligator are fined$750 to $1,500 per offense and sen-tenced up to 30 days in jail. In addition,guilty persons must pay a civil restitutionfee for the estimated replacement costsof the wildlife taken. The civil restitutionfee for a whitetail deer is $525; the feesfor alligators are $35 per foot and $2.21per pound.

The Department of Wildlife andFisheries estimates only 300 Louisianablack bears remain, with four to five ofthem killed illegally each year. Wildlifelaw enforcement officers have been ableto solve only one to two of thesepoaching cases because the remainingcarcasses are either never recovered orhave been found three or more dayspostmortem. Since Louisiana black bearsare a threatened species, the combinedpenalties are considerably higher at$11,000 and up to 120 days in jail.Louisiana collects approximately$350,000 annually in penalties andrestitution fees for the successfullyprosecuted cases of deer and alligator.Even by a conservative estimate, theincorporation of forensic entomologymay result in additional $100,000 inrecovered fines and restitution fees fordeer and alligator alone.

Preliminary results obtained fromthis research highlight the differences insuccession patterns that must be consid-ered when prosecuting in court. Futureresearch will explore the feasibility ofapplying forensic entomology to abroader spectrum of wildlife species.This research, in combination withworkshops for law enforcement officials,will ensure that the use of rigorous,standardized entomological data willbecome a routine part of crime sceneinvestigation of humans and wildlife.


The importance of entomology to legal investigations hasbeen known for several hundred years, but it has been recognizedas a separate specialty only for the last 20 years or so. Forensicentomology applies to any aspect of insect study that may aid inresolving a situation that goes through the legal system. This mayrange from insect parts found in food products to determiningthe time of death of a crime victim who goes undiscovered forseveral days.

With humans there are various methods of determining thetime of death, such as rigor mortis and body temperature. Butafter 24 to 36 hours, these methods and others no longer givevalid results. It is then that the services of the forensic entomolo-gist become valuable.

Certain insects are highly attracted to dead and decomposingbodies, and their life cycles allow experts to determine the timeof death. The insects most beneficial in this process are flies,specifically blowflies and flesh flies.

Familiarity with the biology and geographic distribution ofthese flies and the ability to identify specimens from all stages ofthe life cycle are what the forensic entomologist can bring to theinvestigation process. The time of death is established based on

the known length of time for the flies to develop to that stageunder a given set of conditions. Environmental factors (tempera-ture, rainfall, kind of habitat and length of daylight hours) affect eggdeposition and length of development.

Murderers frequently go to extreme lengths to cover uptheir crime and lead investigators in the wrong direction. Victimshave been discovered submerged in water, burned in automo-biles and wrapped in various kinds of materials to conceal them.They often are found in wooded areas, ditches and overgrownvacant lots. Research at LSU has been conducted to provide asmuch information as possible to help law enforcement personnelwith their investigations.

Because of the similarities of swine tissue to that of humans,pigs have been used most frequently for field tests. Data havebeen collected from tests carried out in pastures, ditches,riverbanks, pine forests, hardwood forests, car trunks and burnedvehicles. Field tests have been carried out in all four seasons of theyear and at the time of both the new moon and full moon.

Since it is not always possible for an entomologist to go to thecrime scene, it is necessary to educate and train others to collectand preserve entomological evidence and to record informationon habitat and ambient conditions. The training of law enforce-ment personnel and crime scene investigators is an importantpart of the LSU AgCenter’s outreach educational program.

Forensic Entomology Aids Crime InvestigationThe ability to identify specimens from all stages

of an insect’s life cycle providescritical information.

Two claims to fame for C. Lamar Meek, professor in theDepartment of Entomology who died June 27, 2000, were hismosquito research and forensic entomology research. In 1979,Meek became LSU’s chief mosquito scientist, replacing C.Dayton Steelman, who moved to an administrative position.Meek became a driving force in the Louisiana Mosquito ControlAssociation, twice serving as its president. He edited theLouisiana Mosquito Control Association Training Manual formosquito control personnel. He was also instrumental inorganizing an annual spring workshop for hands-on training formosquito control district personnel. Meek was a strong advo-cate of having mosquito control workers tested and certifiedby the Louisiana Department of Agriculture and Forestry andtook the lead role in writing the tests used for this purpose.Meek died of heart failure while conducting a mosquito controlexperiment in Cleveland, Miss. During his last 12 years, hefocused on contributing to knowledge of forensic entomologyin addition to his mosquito research. He published more than20 papers and a book chapter about necrophilous arthropodsin relation to investigations of homocides and deaths of high-profile wildlife. He testified in more than 10 criminal trials,including the case upon which the film “Dead Man Walking”was based. Linda Foster Benedict

C. Lamar MeekA leader in mosquito research and forensic entomology

C. Lamar Meek


Jeanine W. Tessmer, Adjunct Instructor, Department of Entomology,and former graduate student of C. Lamar Meek

This photo was provided courtesy of the Baton Rouge Advocate.The photographer was Lori Waselchuk.


osquitoes have been cussed,discussed and described in written detailsince the first explorers traveled throughthe area now known as Louisiana.Because of their need for blood fromhuman or animal hosts, mosquitoes havehistorically caused misery and sufferingto Louisiana citizens and visitors alike.

Throughout Louisiana’s history,massive numbers of mosquitoes havethrived along the Gulf Coast fromPlaquemines west through CameronParish. These parishes include riceproduction, swamps and bayou areas.Massive outbreaks occurring on seven-to 10-year cycles, and especially afterhurricanes, often have resulted in cattleand other domestic animal deathsbecause of blood loss and suffocationcaused by blockage of air passages. Theimpact of mosquitoes on tourism andtheir potential as carriers of organismsthat cause disease resulted in theestablishment of mosquito abatementdistricts in Jefferson, Orleans, St.Bernard and St. Tammany parishes inthe early 1960s.

Because of public concern over thecontinued impact of mosquitoes onhumans, domestic and wild animals, theLouisiana Agricultural ExperimentStation created a position for a scientistto do research on mosquito populationmanagement in 1965. Research wasconducted in cooperation with theLouisiana Mosquito Control Association,which had researchers at New Orleans,Lafayette and Lake Charles, the existingmosquito abatement districts and theU.S. Department of Agriculture(USDA) Mosquito Research Labora-tory at Lake Charles.

A significant effort was immediatelyinitiated wherein the mosquito abatementdistricts provided funding for a labora-tory technician at LSU to determine thesusceptibility of mosquitoes to theinsecticides in use in mosquito control

programs. Abatement district personnelcollected mosquitoes from their respec-tive parishes and delivered them to LSUwhere the tests were conducted. Thebaseline data established in these testslater identified the development ofinsecticide resistance in mosquitoes toseveral insecticides that had been inconstant use in the various parishprograms. This information providedadvance warning that resulted inpreventing resistance development in thedistricts by their changing to alternativeinsecticides.

In 1971, mosquitoes carryingVenezuelan encephalitis crossed theborder between Mexico and Texas,killing horses and dogs and threateningthe human population. Massive numbersof mosquitoes were in coastal Texas andLouisiana at this time, and this stimu-lated the U.S. Department of Agricultureto conduct an emergency adult mosquitocontrol program in Texas that includedCameron and Calcasieu parishes inLouisiana. The emergency programinvolved the aerial application of ultra-low-volume insecticide and effectivelycontrolled adult mosquitoes and pro-tected the horse population for a three-week period until a horse vaccine couldbe administered. LSU AgCenter scien-tists worked with USDA’s Animal andPlant Health Inspection Service (APHIS)personnel during this program. No horseor human cases of Venezuelan encepha-litis occurred in Louisiana. This mos-quito control program provided alarge-scale demonstration that provedto the citizens of the coastal parishesthat mosquitoes could be controlledeffectively.

LSU AgCenter scientists went on tohelp form mosquito control programs inCameron, Calcasieu, Jefferson Davis andVermilion parishes. Later, the LSUAgCenter led the way to initiatingmosquito control programs in East Baton

Rouge and Ouachita parishes. Since themid-1970s, many other mosquito controlprograms have been initiated in otherparishes.

Research on mosquitoes at LSU hasincluded the identification of themosquitoes responsible for transmittingdog heartworm, anaplasmosis and equineinfectious anemia (swamp fever),identification of host animals thatprovide most of the mosquito bloodmeals and the impact of wildlife habitatmanagement on mosquito production.The mosquito research program at LSUreceived national and internationalrecognition for its leadership in aconsortium of scientists from riceproduction states that conducted researchfrom 1979 to 1993 on the biology andcontrol of mosquitoes produced in ricefields.

In addition, landmark research thatdetermined the effect of mosquitoattacks on cattle production, identifyingBrahman-breed resistance to mosquitoes,was conducted at the Rice ResearchStation in Crowley. The mosquitoabatement districts have received helpfulinformation on the integrated manage-ment of mosquitoes in many aquatichabitats, impact of insecticides appliedfor mosquito control on non-targetaquatic organisms and mark-release-recapture studies that determinedmosquito dispersal. Countless experi-ments have been conducted to determinethe efficacy of many different insecti-cides, biological agents and habitatmanipulation for managing mosquitopopulations.

Taking the BiteOut of MosquitoesSince 1965, LSU AgCenter researchhas contributed to abatement ofthis potentially dangerous pest.

C. Dayton Steelman and Dennis L. Wallette Jr.

C. Dayton Steelman, University of Arkansas,formerly a professor in the Department ofEntomology, and Assistant Director, LouisianaAgricultural Experiment Station; and Dennis L.Wallette Jr., East Baton Rouge MosquitoAbatement, formerly a graduate student of C.Lamar Meek

M


ater quality monitoring of urbanenvironments indicates high pollutantloading in the first runoff of rain knownas “first flush.” As precipitation falls, itpicks up contaminants from litteredstreets, drainage ditches, petroleumresidues from cars, heavy metals and tarresidues from roads, and chemicalsapplied for fertilization and insectcontrol.

Lawn and garden care practiceshave the potential to significantly andadversely affect the water quality ofurban waterways. The major pollutantsfound in runoff from urban areas includesediment eroded from bare-soil areas,nutrients from over-fertilization andoxygen-demanding substances such asleaf and grass clippings. In addition,excessive pesticide use, along with over-watering, can contribute to water qualitydegradation.

Other household activities that maygenerate pollutants include use of paints,solvents, detergents, cleaners andautomotive products such as oil andantifreeze.

Proper management techniques canreduce and possibly eliminate the needfor fertilization and pesticide use in theurban setting. These include: (1) mowingthe lawn when grass blades are at anappropriate height, (2) leaving grassclippings on lawn (if mowed at properheight) to provide nutrients, (3) testingsoils to determine necessary amount offertilizer, (4) using slow-releasingfertilizers, (5) determining pest problemsfor appropriate selection and applicationof pesticides and (6) composting yardwastes for future source of nutrients.Most of these practices will also reducethe cost of lawn maintenance.

Impervious surfaces surroundinghomes and businesses in the form ofdriveways, sidewalks and patios forcerainwater to run off. Cities experiencenine times more runoff than woodedareas. Runoff from city streets isgenerally channeled into storm drains

and drainage ditches. A recent studyindicated that E. coli bacteria regrowthrough cloning within storm drains andsediments of urban streams. The studyalso concluded that nonhuman speciesare the dominant sources of E. coli to thestream and its tributaries. The majornonhuman mammal contributors areraccoons, dogs, deer and rats.

with good soil drainage, it is recom-mended to capture and then spread andinfiltrate the rainwater runoff from pavedareas and roofs.

Oil stains and outdoor spills ofantifreeze, brake fluid and other automo-tive fluids on driveways and in parkinglots are easily carried away by a rain-storm. One quart of oil can contaminateup to two million gallons of drinkingwater. It has been estimated that everythree weeks more oil is deposited ondriveways and streets in the UnitedStates than was deposited in the Valdezoil spill in Alaska. Routine maintenancecan prevent cars from leaking. Pans,carpet scraps and matting can catch dripswhen the car is parked at home.

The LSU AgCenter has educationalprograms that address nonpoint-sourcepollution in urban areas:

A series of one-page fact sheetson “You Can Help Protect Our Waters”is available free from any parish exten-sion office and online at the LSUAgCenter’s website.

Extension agents give demon-strations and teach water-saving tech-niques with a traveling exhibit called the“Splashmobile.”

Extension agents provideworkshops for teachers as requested.

Margaret Frey, Extension Agent in Environmen-tal Education, LSU AgCenter, Baton Rouge, La.

Nonpoint-Source Pollution—Urban StyleMargaret Frey

Reducing the amount of excessiverunoff is possible by using more porouspaving surfaces that allow rainwater tosoak into the ground. Significantstrides have been made indeveloping porous asphaltpavement in the last threedecades. The material is similarto conventional asphalt indurability, but it contains a muchsmaller percentage of fineparticles. As a result, the asphaltallows water to soak through tothe base material and into the soilbelow.

Roof downspouts spill ontodriveways that are graded downto the street gutters, which, inturn, lead to storm drains thatdump accumulated rainwater intodrainage canals. The destructivedeluges of this collected rainerode streambanks. In places

W

Illustrations by Ana Velez

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lthough some Louisianahomeowners use professional lawn careservices, many homeowners maintaintheir own lawns. While many profes-sional applicators use liquid fertilizersand pesticides, granular products areeasier for homeowners to apply. Abewildering array of lawn spreaders isavailable for this purpose, and manyhomeowners do not know how to selector effectively use a spreader. A series ofstudies was conducted at the HammondResearch Station to provide informationon this topic.

Two basic types of spreaders areavailable for home lawn use: drop androtary. Drop spreaders have a full-widthagitator over a row of metering ports andgranules are dropped straight down. Thewidth of the swath of a drop spreader isequal to the width of the hopper. Dropspreaders generally give a more uniformdistribution pattern, if used correctly, butare sensitive to correct swath width. Oneach pass, the wheels must be over-lapped inside the previous wheel tracksto avoid turf stripes. Rotary (sometimescalled broadcast) spreaders typicallyhave one to three metering ports thatdrop the granules onto a spinningimpeller. The swath width varies withproduct but is wider than the spreaderhopper. Rotary spreaders have widerpatterns so the product can be spreadover a lawn faster than with a dropspreader. Rotary spreaders are moreforgiving of swath width errors, but theirspreader pattern may not be as uniform.More care is needed with rotary spread-ers to avoid throwing granules intononturf areas.

Most drop and rotary homeownerspreaders are made with plastic hoppers.A study comparing three plastic home-owner drop spreaders with an older steelhomeowner drop spreader and a profes-sional steel drop spreader demonstratedthat some of the newer plastic spreaderscan give acceptable metering uniformity(Figure 1). The Scotts AccuGreen 1000was both the lowest cost spreader in thetest and the most uniform of the home-owner models. Consistency from onespreader to another of the same modelhas not been tested.

Another study evaluated thedistribution patterns from six home-owner rotary spreaders (Figure 2). Thespreaders were tested with three repre-sentative granular materials. With allspreaders, except the Scotts SpeedyGreen 1000, the swath width that gavean acceptable pattern was narrower thanwas apparent from the overall throw

handle was raised only 3 inches anddecreased 63 percent when the handlewas lowered 3 inches. The ScottAccuGreen 3000 exhibited a similarproblem, but the results were lessextreme since the hopper was not asthick on the Scotts spreader. Therefore,short or tall applicators would obtaindifferent delivery rates than people of

Richard L. Parish, Professor, HammondResearch Station, Hammond, La.

width. In cases where the manufacturerclaimed a swath width, the effectivewidth found in this study was consider-ably narrower than what was claimed.

The popularity of plastic spreaderhoppers has led to another problem.Plastic drop spreader hoppers are thickerthan steel. This causes the effectiveopening of the ports and thus thedelivery rate to change when the hopperis rotated forward or back, as will occurwith changes in handle height. A studyof two plastic drop spreaders demon-strated clearly that the thicker the hoppermaterial, the more the rate changes withhandle height. The delivery rate of theRepublic/Sears/K-Mart EZ Dropspreader decreased 26 percent when the

average height, even when using thesame spreader setting. The importantpoint is to operate the spreader with thehopper level. This may put the handle atan uncomfortable height or angle for somepeople with some spreaders, but willprovide the most reliable delivery rate.

Homeowner spreader models,whether drop or rotary, are designed tobe pushed forward. It is sometimestempting to pull spreaders backward.When operating on soft ground, as whenfertilizing a garden or seeding a newlawn, for instance, pulling a spreader

Figure 2. Spreaders used for the rotary spreader pattern study: Scotts Speedy Green 1000,Scotts Speedy Green 3000, Republic/Sears/K-Mart EZ Broadcast, Cyclone, Spyker andVigoro.

Figure 1. Spreaders used for the drop spreader metering uniformity study: Gandyprofessional (steel), Scotts AccuGreen 1000 (plastic), Republic/Sears/K-Mart EZ Drop(plastic), Scotts AccuGreen 3000 (plastic), obsolete Scotts PF-1 (steel).

Fertilizer Spreadersfor Home Lawns

Photos by Richard L. ParishA

Richard L. Parish


backward requires much less effort thanpushing it forward. Unfortunately,pulling these spreaders backward candrastically change delivery rate and canalso change the pattern from rotaryspreaders. Two plastic homeowner dropspreaders (Republic/Sears/K-Mart EZDrop and Scotts AccuGreen 3000) werecompared with a Gandy professionaldrop spreader. The plastic spreadersdelivered more material when pulledbackward. The Republic/Sears/K-Martspreader, which had the thickest hopper,had a delivery rate 271 percent higherwhen pulled backward at a low settingand 127 percent higher when pulledbackward at a high setting than whenpushed forward. The correspondingchanges with the Scott spreader were145 percent and 180 percent.

Another study evaluated a new lawnspreader that claims to combine thebenefits of drop and rotary spreaders.The Ames Deluxe 2-in-1 spreader has ashroud around the impeller to restrictand control the throw pattern (Figure 3).The patterns obtained with five differentgranular materials at the width recom-

demonstrated that some plastic dropspreaders can deliver acceptable meter-ing uniformity, if a quality spreader isselected and if the spreader is usedcorrectly. Drop spreaders with plastichoppers are sensitive to handle heightand should be operated with the hopperlevel. The shrouded rotary spreader doesnot live up to its potential and does notoperate effectively. Current homeownerrotary spreaders tend to have skewedpatterns and require narrow patterns toachieve acceptable pattern uniformity.Unfortunately, homeowners cannotalways rely on the settings provided withthe spreader and on the product label.The settings are often incorrect. Somecompanies (Scotts, Bayer, Andersons) doprovide accurate settings based either ontheir own setting development or onsetting development by programs such asthe one at the Hammond ResearchStation. In considering whether to usehomeowner rotary spreader width andsetting recommendations by manufactur-ers, keep in mind that if the recom-mended width is more than 2 to 4 feet,the settings are probably wrong.

Figure 3. Ames Deluxe 2-in-1 spreader withelliptical shroud.

mended by Ames were not uniform. Itwas necessary to reduce the effectiveswath width to only 1 foot when usingthe shroud to obtain patterns withacceptable uniformity.

This series of spreader tests has

Jennifer Acosta, senior, left, and Trent Roddy, senior, buyice cream at the LSU AgCenter’s Dairy Store from CharlesSurbeck, junior. All three are from New Orleans. The storeis open year-round and offers such original flavors as OakFudge Alley and Bourbon Street Vanilla Bean.

Long a campus fixture, the LSU AgCenter’s Dairy Store and itsaccompanying creamery have offered teaching and research opportuni-ties for the Department of Dairy Science as well as ice cream treats.

The creamery, a small-scale production facility, is used to teachstudents to make ice cream and cheese and produces about 6,000 gallonsof ice cream and 5,000 pounds of cheese each year.

Operated almost exclusively by student labor, the store in itscurrent location has been open since 1972, said Chuck Boeneke, aninstructor and manager of the creamery. Although a creamery has beenoperated at various locations since 1906, the first dairy store on campusopened in 1929 and closed in 1956 when the creamery moved to itscurrent location.

Jack Losso, a researcher in the Department of Food Science, uses thecreamery to remove fats from milk to prepare proteins on a large scalefor study. In one project, he is investigating how milk proteins can replacegums as stabilizers in foods such as salad dressings and sauces.

Ron Gough in the Department of Dairy Science uses the creameryto find better ways to treat dairy plant wastewater before the water isreleased into municipal water treatment systems.

“We want to be able to manage and predict how the pollutingcomponents of this waste stream can be removed and release a cleanerliquid into the municipal wastewater stream,” he said.

In another project, Gough and Boeneke are evaluating manufactur-ing processes for creole cream cheese.

“It’s a limited commercial product that requires hand labor butresults in a high-quality product,” said Gough, who is working with aLouisiana dairy producer who wants to get into the manufacturingbusiness to supply creole cream cheese to restaurants and specialtystores. Rick Bogren

Creamery Provides Rich Source of Research Information


Photo by Mark Claesgens


nvironmental horticulture affectsall Louisiana residents, especially inurban areas, and although not widelyrecognized, is a critical sector of thestate’s economy. Environmental horti-culture is concerned with the art andscience of breeding, propagating,installing and maintaining ornamentalplants to enhance and improve thehuman environment. For economicresearch purposes, the U.S. Departmentof Agriculture classifies ornamentalplants into floriculture and environmen-tal horticulture. Floriculture crops aregrown predominantly under protectivecover and include cut flowers andgreens, potted flowering and foliageplants, and bedding plants. Environmen-tal horticulture crops are grown outdoorsand include trees, shrubs, ground covers,vines, bulbs, turfgrass, and fruit and nutplants.

These two crop areas are the fastestgrowing segment of U.S. agriculture,ranked as the seventh most importantcommodity group, and generated $12billion in grower cash receipts in 1998.Based on total economic output (produc-ers of plants, service businesses thatinclude retail sales and landscapeservices, and equipment and accessorybusinesses), the floriculture and environ-mental horticulture sector ranks as thesecond most important segment in U.S.agriculture. Retail expenditures for allfloriculture and environmental horticul-ture products and services were $55billion or $203 per capita in 1998.

Industry’s Value to LouisianaCash receipts to Louisiana’s

ornamental plant producers in 1999 were$122 million, which ranked this sectorfifth in value among agricultural plantcommodities. The total value of allproducts and services of Louisiana’s

environmental horticul-ture industry is about$1.5 billion annually.This equals the com-bined value of all animalcommodities and placesenvironmental horticul-ture second afterforestry in total eco-nomic impact amongplant commodities.

LSU AgCenterResearch

The LouisianaAgricultural ExperimentStation actively supportsresearch on ornamentalplants grown by nurseryand garden centers andused by landscape firmsand home gardeners tobeautify the urbanenvironment. Followingis a sampling of some ofthat research.

Landscaping addsvalue to homes. Recentresearch by agriculturaleconomists addressedthe impact of specificlandscape attributes (combinations ofdesign style and costs, plant material andplant sizes) on home values in threeLouisiana cities. Customer preferencesthat related to design cost and complex-ity, plant size and plant material wereanalyzed. Customers placed the highestvalues on homes with the most sophisti-cated landscape designs that containedlarge plants. Design complexity wasfound to be the most important factorthat increased home values, with plantsize and material following in impor-tance. (Figure 1)

Horticulture in the CityResearch at the Louisiana Agricultural Experiment Station

affects many areas of urban life including the plants that addto the aesthetic as well as the tangible benefits of community life.

Gordon E. Holcomb, Allen D. Owings, Dale K. Pollet, Roger A. Hinson,Edward W. Bush, Jeff S. Kuehny, James McCrimmon, Seth J. Johnson,

Peggy Cox, Drew Bates and Timothy J. Raiford

Gordon E. Holcomb, Professor, Department ofPlant Pathology and Crop Physiology; Allen D.Owings, Associate Specialist, and Dale K. Pollet,Specialist, Cooperative Extension Service; RogerA. Hinson, Associate Professor, AgriculturalEconomics and Agribusiness; Edward W. Bush,Assistant Professor, Jeff S. Kuehny, AssociateProfessor, and James McCrimmon, AssociateProfessor, Department of Horticulture; Seth J.Johnson, Professor, Department of Entomology;Peggy Cox, Research Associate, Drew Bates,Associate Professor, and Timothy J. Raiford,Assistant Professor, Burden Research Station;LSU AgCenter, Baton Rouge, La.

Figure 1. Agricultural economists addressed the impact ofspecific landscape attributes (combinations of design style andcosts, plant material and plant sizes) on home values. As part ofthe study, they showed groups of consumers and realtorscomputer-generated images of homes, such as those above,with different levels of landscaping. The strong preference wasfor the high cost designs.

E


Scientists screen ornamentals. LSUAgCenter scientists evaluate cultivars ofbedding plants, trees, shrubs and turfgrasses for their horticultural perfor-mance and disease susceptibility.Evaluation results are passed on toconsumer groups through publications,e-mail, Internet sites, meetings andthrough the news media.

Burden serves as research center.Trials are conducted at Burden ResearchStation in Baton Rouge on annual andperennial plants such as salvia, pansy,petunia, chrysanthemum (garden mums),crape myrtle, impatiens, Indian haw-thorn, lantana, liriope, marigold,ornamental sweet potato, snapdragon,verbena, vinca and zinnia. These trialsprovide information on planting dates forbest performance, new plant species andcultivars and overall performanceratings. These trials also identifycultivars and species with resistance toimportant diseases. In recent trials Indianhawthorne cultivar Olivia was ratedhighly for its resistance to fungal leafspot, but all plants were killed laterbecause of their high susceptibility tofire blight disease. Crape myrtle cultivars

have been identified thatare highly resistant toCercospora leaf spot, aserious disease that causesearly defoliation ofsusceptible cultivars. Scientists devise‘best management’horticulture practices. Aresearch focus is evaluat-ing irrigation, fertilizationand pest managementpractices used in orna-mental horticulture. Theyare referred to as “bestmanagement practices”and encompass an overallplan to enhance produc-tion and maintenance ofplants using environmen-tally friendly methods.These practices aredesigned to achieve wateruse efficiency, maximumgrowth with minimumfertilizer use, reducednutrient runoff andoptimum pest control withminimum pesticide use.

Select LSU AgCenterrecommendations. TheLSU AgCenter annuallyrecommends and pro-motes outstandingornamental plants forLouisiana landscapescalled “Louisiana

Select.” Selections are also promotedand featured in special displays in retailgarden centers. Since 1996, when theprogram was initiated, Goldstrumrudbeckia, Lady in Red salvia, Foxyfoxglove, several lantana cultivars, baldcypress, New Wonder scaevola, Telstardianthus, Watchet azalea, Henry’sGarnet Virginia willow, HomesteadPurple verbena, mayhaw and NewOrleans Red coleus have been named“Louisiana Select” plants.

Landscape with vegetables. Sometraditional garden vegetables add beautyand diversity to landscapes. Leaf lettucecultivars have been evaluated for theirpotential as bedding plants because oftheir pleasing variation in color andtexture. Red and maroon cultivars(Vulcan, Galactic, Redino, Carisma, RedSales, Lollo Rosa, Cerize) performedwell. An additional benefit to growingthese colorful vegetable plants in thelandscape is that they also make finesalads. Basil cultivars have also beenevaluated for landscape performance anddisease resistance. Cultivars GreenRuffles and Purple Ruffles are attractivelandscape plants because of their foliagecolor and texture but were found to behighly susceptible to a new bacterial leafspot disease.

Research leads to better wax andcrape myrtles. LSU AgCenter scientistsare studying chemical control of undesir-able basal sprouting in wax myrtles,small native trees often used in land-

A hibiscus, above, and a rose at the LSU AgCenter’s BurdenResearch Station, where much of the research onornamentals is conducted.

Baton Rouge residents and visitors benefit from the efforts of many local plant societiesand organizations. Independence Park in Baton Rouge includes an attractive rose gardenmaintained by the local chapter of the American Rose Society.

Photos by Gordon E. Holcomb


Crape myrtles add to the beauty of the landscape on the LSU campus in Baton Rouge.

scapes. Plant growth regulators, knownto be effective for controllingwatersprouts and rootsuckers on otherlandscape trees, are being evaluated onwax myrtle. The crape myrtle cultivarNatchez is being used to evaluate theinfluence of three levels of pruning onoverall appearance, bloom quality anddisease and insect susceptibility oflandscape plants.

Grow better grass. Scientists atBurden evaluate turfgrass cultivars,some in conjunction with the U.S.Department of Agriculture NationalTurfgrass Evaluation Program, for theirhorticultural performance qualities.They also do research on turfgrass weedcontrol, shade tolerance, fertility andmowing heights. Other turfgrassresearch has evaluated waterloggingtolerance of lawn grasses and use ofcarpetgrass in lawns. Zoysiagrass and St.Augustinegrass cultivars have beenidentified that show disease resistance.

A rose is a rose is a rose. BurdenResearch Station maintains an All-

America Rose Selections display gardenthat is also used for cultivar performanceand disease susceptibility evaluations.More than 100 cultivars are on displaythat belong to various rose classes suchas hybrid tea, ground cover, miniature,shrub, floribunda, grandiflora, climberand various species and classes ofantique roses. Roses are susceptible toseveral serious disease problems, and thedisplay garden is used to evaluatecultivars for susceptibility to black spot,downy and powdery mildew andDothiorella flower spot. Evaluations in2000 showed that Knock Out showedoutstanding resistance to black spot.

Gingers and poinsettias, too.Floricultural plants being evaluatedinclude gingers and poinsettias. A gingergarden has been established at Burden.Poinsettias, popular holiday pottedplants, are placed on display to allowconsumers, garden center personnel andgrowers to evaluate them.

Getting rid of pests. Insect pests candamage urban landscapes. An example is

lace bug damage to azaleas. Controlmethods had relied on repeated insecti-cide treatments throughout the growingseason. Through research, entomologistsdetermined that fewer insecticideapplications are needed for lace bugcontrol if plant inspections are made inearly March and followed by earlyinsecticide applications.

Crape myrtle aphids are anotherinsect pest that had been commonlycontrolled by frequent insecticideapplications. A simpler and moreeffective control method was developedthat consists of painting a slurry of fourparts acephate insecticide plus one partwater in a band around the lower trunkof crape myrtle trees. The insecticide isabsorbed and translocated to the leaveswhere it kills aphids when they feed.Acephate applications should be made inApril when aphids first appear and againin late summer. This eliminates the needfor making frequent spray applicationsthroughout the spring and summer.


Non-profit Org.U.S. Postage

PAIDPermit No. 733Baton Rouge, LA

Louisiana Agricultural Experiment StationLouisiana State University Agricultural CenterP.O. Box 25100Baton Rouge, LA 70894-5100

Inside:

Red imported fire ants areubiquitous in Louisiana, but researchersare trying to stem their spread.

Page 6

The LSU AgCenter is taking a three-pronged approach to finding solutionsto the state’s termite problem.

Page 9

Research shows that woodlands anddairy farm pastures can contribute towater contamination. Page 16

Forensic entomology research helpstrack down poachers.

Page 18

about 90 hours. Some never stop. They’re available to helpwhenever they’re asked.”

Another way the New Orleans-area Master Gardenersserve is helping with the renowned fall and spring garden showsat City Park, which attract 6,000 to 7,000 visitors. The volunteersdo everything from laminating signs to checking audio-visualequipment and taking tickets.

“We couldn’t do the shows without them,” said Monica Lear,LSU AgCenter specialist in Orleans Parish. She supervises about65 Master Gardener volunteers.

Robert Turley, LSU AgCenter specialist in Calcasieu Parish,just finished his first Master Gardener class and certified eightvolunteers. They will help him with the Lake Charles garden showand with his demonstration garden.

“Classes are usually bigger than that,” Koske said. “Wegenerally have about 25. Some parishes go together to get thatmany.”

Master Gardeners do a variety of projects. For example, theShreveport Master Gardeners put on a popular annual gardentour that raises around $5,000 for supplies and reference mate-rials for their program. They also publish a gardening newsletter.

The New Orleans group hosts a website with gardeningadvice.

Baton Rouge Master Gardeners have formed an alliance withHabitat for Humanity to help new homeowners get established.

The Tangipahoa Parish Master Gardeners, under the super-vision of LSU AgCenter agent Annie Coco, restored a camelliacollection at the LSU AgCenter’s Hammond Research Station.

Master Gardener training is open to any adult available totake the classes and do volunteer work. More information may beobtained from any LSU AgCenter parish extension office or bycontacting Koske at 225-578-2222, or [email protected].

Linda Foster Benedict

Wes Gladhart of Metairie, retiredpharmacist and devout gardener, spendsmany a Tuesday afternoon in the LSUAgCenter’s Orleans Parish ExtensionOffice answering gardening questions –free.

He is one of about 400 volunteerMaster Gardeners throughout Louisianatrained by LSU AgCenter specialists toextend their educational services.

“Most questions are seasonal so Ihave many of the answers ready,” said Gladhart, 70, whoseparticular specialty is ferns.

Of course, there are those unusual calls, such as the womanwho wanted advice on how to get the squirrels out of her attic.

“I learn a lot from answering the questions,” he said.These Master Gardeners, most of whom are women, do this

volunteer work because they love gardening. They love learning.And they like telling others what they’ve learned, said Tom Koske,LSU AgCenter horticulturist and the coordinator of MasterGardener training.

The program, which is nationwide, began in Louisiana in NewOrleans about 10 years ago. It has since spread to 19 of the state’s64 parishes with the goal to expand as needed, Koske said.

LSU AgCenter horticulture agents provide 40 to 50 hours oftraining for prospective Master Gardeners every spring and fall atvarious locales in the state. All but a handful finish and attain thetitle, said Koske, who developed the training manual.

Although they pay for the materials, the Master Gardenersdo not have to pay for the training. Instead, they must commit to40 hours of volunteer service for the next year in their parishes.

“Most give far more than that,” Koske said. “Some average

‘Master Gardeners’ teach others to get growing

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Urban Agriculture Issue - LSU AgCenter Agriculture Issue. 2 Louisiana Agriculture, ... Please give credit to the author and to ... James F. Beatty and Eric C. Achberger