ations.• The availability of labor.• Whether soil moisture is suitable.

Apply Cultivation at Correct SoilMoisture

Different cultivation methods are mosteffective at a particular soil moisture levelat the time of application. If soil moistureis outside this range, effectiveness de-clines.

Methods that have loosening action onthe soil are more effective if the soil issomewhat drier than field capacity. Fieldcapacity would be the soil moisture at oneday after a good irrigation or rainfall eventon a fine textured soil. "Somewhat drier"would be two to four days after irrigationor rainfall.

If the soil becomes too dry, the imple-ment will not be able to penetrate and willlose its effectiveness. In contrast, on ex-cessi vely moist soils, little loosening ac-tion occurs.

For operations that penetrate the soil, butwith minimal loosening action, a soilmoisture near field capacity would bebest. Any cultivation should be avoidedat soil moisture above (wetter than) fieldcapacity to avoid destruction of the soilstructure.

Report fromDown Under

Evaluate your ResultsThe benefit of cultivation are often dif-

ficult to evaluate. You should be able toobserve improved filtration/percolation,better rooting, increased shoot growth orloosening of the soil; this, the growershould see fewer of the symptoms thatrepresent clues to the presence of soilphysical problems. Using the same proce-dures to identify the primary problems ona site is beneficial in identifying results.Careful observation of the soil profile isparticularly beneficial. Sometimes an un-treated area can be left for comparison.

While evaluation of cultivation results isdifficult, it is well worth the effort to ad-just your program over time. Certainlythis is one area where the experience ofsuperintendent and observation over timeare essential to evaluate cultivation pro-gram effectiveness.

In conclusion, cultivation programsevolve by long-term experience on a par-ticular site (i.e., trial and error); using whatsomeone else has found effective; usingthe "latest" device with hopes it will be theright operation; or by a careful analysis ofthe problem, evaluation of different op-tions and correct use of various proce-dures.

The main reason that better cultivationprograms have not evolved are:• Difficulty in determining the primary

soil physical problem(s) present on asite.

• A lack of specific, comparative data onhow each cultivation method influencessoil, physical conditions and turfgrassgrowth.

Historically, growers have had to rely onempirical observation to determine therelative effectiveness of different tech-niques. In recent years, research projectssupported by the USGA Green Section atMichigan State University and the Uni-versity of Georgia have greatly increasedour knowledge about various methods.Much of this information will be publish-ed over the next year.

Because soil physical problems exist onalmost all golf courses and cultivation is amain tool to alleviate these problems, thedevelopment of a sound cultivation pro-gram is important. The same logical andscientific approach used in formulatingcultivation programs as with other cul-tural practices will result in improved andmore efficient cultivation and better turf.

[Reproduced from Golf Course Management,Vol. 58, August, 1990]

InAugust of this year I had the opportunity to take part in theMid-Conference meeting of the Board of Directors of theInternational Turfgrass Society (ITS) in Sydney, Australia. Themajor focus of the society, which was founded in 1969, is to hostthe "International Turfgrass Research Conference" (ITRC). Thisconference is held every four years, and a different country fromaround the world hosts the event. The mid-conference meetingwas held in Sydney, Australia, because they are the hosts of the8th ITRC to be held in July, 1997. My involvement with thisorganization stems from the fact that Canada has offered to hostthe 9th International Turfgrass Research Conference to be held in2001 in Toronto and I have volunteered to be one of the keyorganizers. The Board of Directors of the Sports Turf Associationawarding me a travel grant toward the cost of my travel whichmade it possible for me to attend this meeting. This travel grantwas greatly appreciated.

I would like to give the Sports Turf Association membershipsome information about the International Turfgrass Society aswell as some technical highlights from my trip to Australia. As I

mentioned the Society sponsors a turf research conference everyfour years. Of note at the last ITRC held in Palm Beach, Florida,was the number of papers presented on sports turf. There was ahalf day symposia on "Quantification of Surface Characteristicsof Sports Fields" where 7 papers were presented. The reason thatI mention this is that when the ITRC is held in Canada this willbe an excellent opportunity to hear world renown researchers talk:about their work on sports fields. I know 2001 seems a long waydown the road, but it will be upon us before we know it.

As a board member of ITS, I sit on the Board of Directors withDirectors from the United States, New Zealand, Australia, Japan,Denmark, France and England. Our task at the Mid-Conferencemeeting was to help organize the conference for 1997. The ITRCis a week long conference with a one day field trip to turf sites ofinterest in the middle of the week.

We had the opportunity to visit several potential sites whichcould be included in the ITRC turf tour in Sydney. All of thesesites were growing warm season turfgrasses. Our tour visited theRoyal Botanic Gardens where there are several turf species dem-onstration plots, the Australian Golf Club where there are somereplicated turf variety trials, Sydney Race Track which has aturfed track, the Olympic Warm-up Track and the AustralianTurfgrass Research Institute which is a self-supporting institute.This institute offers consulting, soil testing, pest diagnosis as wellas research testing of new turf products and pesticides. There is alot of interest in turf at the moment in Australia because of thefact that they are hosting the Olympics in the year 2000.

Much of the interesting information from my trip to Australia

was gleaned from conversations with ITS board members. We areall familiar with the project which involved moving turfgrass tothe Pontiac Silverdome for World Cup 1994 which was headedup by Trey Rogers of Michigan State University. There were alsoprojects undertaken for World Cup 1994 which involved puttingin temporary sod over artificial turf in stadiums such as Meadow-lands Stadium in New Jersey and Giants Stadium in New York.These techniques involves placing plywood on top of the artificialturf followed by up to three layers of polyethy lene and geotextiles.The agronomists had to guarantee that at the end of the soccergames that the artificial turf would be as good as new. Thegeotextiles were topped with a layer of sand anywhere from 3-10inches and then large rolls of bermudagrass sod were laid on top.Bermudagrass is not normally grown in the Northeast but it wasfelt that they would withstand the wear and the temperatures betterthat cool season turf species. This all took place from a month to3 weeks before the soccer games. At the end of the games theorganizers had as little as 24 hours in some cases to bring the fieldsback to artificial turf. Since the World Cup of soccer there havebeen several exhibition soccer games which have taken place inthe U.S. featuring European teams. At these events artificial turfhas been covered and thin layers of sand (as little as 3 inches havebeen brought in) and thick cut sod (1.5 inches) has been placed ontop. Dr. Jim Watson of Toro International will be talking aboutsome of these projects in his keynote speech at the upcoming 1996Ontario Turfgrass Symposium.

Dr. Jim Watson also reported on work being done at MichiganState University on use of crumb rubber (recycled tires which havebeen ground up) as a topdressing for heavy wear areas in sportsfields. A one time application on 1/4 inch provides good protectionof turfgrass crowns from wear. This also has been useful for hightraffic areas in passive parks and golf courses where cart traffic isheavy. This technique could easily be adopted by Ontario sportsturf managers.

Researchers from New Zealand are conducting trials on a newtype of turf which consists of natural grass grown into a syntheticmatting on a sand base. The result is a surface with the playabilityof natural grass with the wear resistance and durability of syntheticturf. This type of turf is compatible with a Prescription AthleticTurf system or any other field construction, provided there is gooddrainage. Maintenance practices are very similar to a natural turffield, however the field could not be aerated but could be verticutto control thatch. Water use may be less because the mat providesa barrier which slows down evapotranspiration. Optimum mow-ing height for this type of system is 1 1/2 inches which is similarto a natural turf field. There are two fields in the United Stateswhich have this system - Rice Stadium at the University of Utahand University of California at Los Angeles practice field. Thissystem also shows promise for golf tees and walk-off areas neargreens. (see following article)

New Zealand has also developed protocols for measuring thequality of sports turf surfaces. The idea behind this is to have aminimum standard for sports field surfaces. If a field falls belowthe minimum the teams are not obligated to use the field. Themotivation is to provide a high quality, safe playing surface for allathletes.

The ITS board member from Japan reported on the currenteconomic recession in Japan. Although golf course constructionis down by 20% there is an increase in interest in sports fieldconstruction. This has partly been triggered by the fact that Japanwill be hosting the World Cup Soccer tournament in the year 2002.

As you can see there are many new products and techniquesbeing investigated around the world to make your job as turfmanagers easier, or more challenging. By the time 2001 arrivesthere will be many more innovations. I hope many of you willmark your calendars for the 9th International Turfgrass ResearchConference to be held in Toronto in July 2001. Again, I want tothank the Sports Turf Association for making this trip possible.

Proponents from both the artificial andnatural turf will be thrilled with thelatest ally in athletic turf surfaces: Sport-Grass.

The invention of sport field expert JerryBergevin, president of Turf Systems Inter-national, SportGrass consists of naturalgrass growing into a synthetic matting.Grass grows down through the syntheticbacking and in between fibrulated syn-thetic strands, which protect the crownand roots of the plant.

The results is a surface with playabilityof natural grass and the wear resistanceand durability characteristics of syntheticturf. The natural turf cushions the impactof sports activity, and the artificial turf andmatting below act as an anchor to reduce- if not eliminate - divots.

SportsGrass is available as sod, or it canbe established on site, as it was this pastsummer at the University of Utah's RiceStadium, the first major SportsGrass in-stallation in the U.S.

Brian Nelson, director of buildings andgrounds at the university, says the fieldhas held up "extremely well" after prac-tices and two full games. A pregerminatedryegrass mix was used to fill in minimalwear areas - which the company saysshould be expected - but Nelson reportsthere were "no divots whatsoever."

SportsGrass needs five to six weeks toestablish, after which the grass has grownabove the height of the plastic blades, andthe roots have formed a mass of intercon-necting fibres in the soil.SYNTHETIC SECRET - The key to fieldstability seems to lie in the type of syn-thetic material used. SportsGrass usesDesso DLW synthetic turf, manufacturedby Desso DLW Sports Systems, Int.,headquartered in Germany.

"SportsGrass is basically the same ma-terial as a sand-filled synthetic turf. "Allwe've done is modify the material." saysBergevin. The artificial turf is made out ofpolyethylene, which is softer than

The Best ofTuroWorlds?Terry MciverEditor, Landscape Management

Natural and Synthetic TurfJoined for Divot-free 7'Playing Surface. /