THE AUTECOLOGY OF CELTIS LAEVIGATA

IN FLOOD PLAIN FORESTS

OF DENTON COUNTY, TEXAS

APPROVED:

Major Professor

> „ J ClUi-cQ, HP. \< > Minor Professor

m i V n r f i i Director>£>f the Department: \of Biology

Dean of the Graduate School

THE AUTECOLOGY OF CSLTIS LAEVIGATA

IN FLOOD PLAIN FORESTS

OF DENTON COUNTY, TEXAS

THESIS

Presented to the Graduate Council of the

North Texas State University in Partial

Fulfillment of the Requirements

For the Degree of

MASTER OF ARTS

By

Lecil B. Hander, B. A.

Denton, Texas

January, 1970

TABLE OF CONTENTS

Page

LIST OF TABLES iii

LIST OF ILLUSTRATIONS iv

Chapter

I. INTRODUCTION 1

II. LITERATURE SURVEY 5

III. STUDY AREA 10

IV. METHODOLOGY 23

V. RESULTS 27

VI. CONCLUSIONS 61

APPENDIX 64

BIBLIOGRAPHY 95

iii

LIST OF TABLES

Table Page

I. Geographic Coordinates! of Flood Plain Forests Studied 12

II. Analysis of Variance for Balanced Repeated Subsampling 28

III. Lengths of Transects Containing Fifty Hackberry Trees; Analysis of Variance 29

IV. Hackberry Basal Area Totals - Fifty-Tree Transects;

Analysis of Variance . . . , 42,43

V, Hackberry Basal Area Density; Analysis of Variance 44

VI. Average Tree Height per Transect; Analysis of

Variance 45,46

VII. Stand Totals for Bioraass Parameters 47

VIII. Per Cent of Total Tree Density Represented by Hackberry; Analysis of Variance 48

IX. Per Cent Basal Area Attributable to Hackberry; Analysis of Variance 49

X. Twelve-Year Tree-Ring Segment Thickness; Analysis

of Variance 51

XI. Hackberry Reproductives 53

XII. General Observations Regarding Hackberry Phenology 55

XIII. Number of Hackberry Trees per Transect Exhibiting

Specified Phenological Characteristics . . . 56

XIV. Bouyoucos Soil Analysis 57

XV. Analysis of Variance - Fifteen-Minute Hydrometric Readings - B^ Soil Layer 58

XVI. Soil Moisture Factors - Bouyoucos Determination . 59

iv

LIST OF ILLUSTRATIONS

Figure Page

1. Haps of Denton County Showing Stand Locations , . ll

2. A View in Lower Denton Creek 13

3. Aerial View of Lower Denton Creek 15

4. Aerial View of Upper Denton Creek . . . . . . . . 16

5. Aerial View of Lower Elm Fork 17

6. Aerial View of Upper Elm Fork 18

7. A View in Upper Elm Fork 21

8. Map of Hackberry Tree Locations at Lower Denton Creek 31

9. Hap of Hackberry Tree Locations at Upper Denton

Creek 32

10. Hap of Hackberry Tree Locations at Lower Elm Fork 33

11. Map of Hackberry Tree Locations at Upper Elm Fork 34

12. Size Distribution of Hackberry Trees at Lower Denton Creek 36

13. Size Distribution of Hackberry Trees at Upper Denton Creek 36

14. Size Distribution of Hackberry Trees at Lower Elm Fork . . . . . . . . . . . . . . 37

15. Size Distribution of Hackberry Trees at Upper Elm

Fork 37

16. View of 31-Inch Hackberry Tree 40

17. Size Distribution of 600 Sample Hackberry Trees . 41

CHAPTER I

INTRODUCTION

Background

In Denton County, as elsewhere, flood plain forests

form a distinct vegetational community. The hackberry-elm

association along the streams contrasts strongly with the

surrounding grassy prairies and the upland post oak forests.

Few stands remain of the verdant streamside forests, however.

Much of this timberland has been cleared or inundated.

Agriculture, which has played an essential role in the

development of Denton County, has been a prime force in

reducing its wooded flood plain acreage. The deep alluvial

soils are fertile and nearby streams provide irrigation water

supplies and the source of a shallow water table. As the

land is highly productive naturally, so it is productive when

it is farmed. Federal and local governments are called upon

to provide recreation facilities, flood control, and water

supplies for private, municipal, and industrial use. They

respond by constructing reservoir dams which further reduce

the extent of bottomland timber stands.

Of the existing forests most, if not all, have beefc

disturbed by man to varying degrees. During post-settlement

days, timber was the main source of fuel in Denton County,

Limited logging operations provided timber for lumber

production. Presently cattle are permitted to forage through

many of these uncleared bottomlands. Thus within the frame-

work of the progress of civilization, few original flood plain

forests remain in their virgin state.

Statement of the Problem

This thesis describes the present nature of one facet of

some of the flood plain forest stands in Denton County, Texas.

The specific purpose was to demonstrate the presence or absence

of difference between the Celtis laevigata (commonly known as

the hackberry, southern hackberry or sugarberry) populations

in stands on Denton Creek and Elm Fork of the Trinity River.

An attempt was made to determine the cause of variation.

Characteristics were studied as evidence of the current

conditions and of the dynamic aspects of the community.

Approach of the Study

In plant ecology, most field studies have been performed

from a community point of view. Constituent organisms of a

community exist as parts of a closely interrelated functional

unit. The dynamics of this unit is the concern of synecology.

Animal studies taking a community point of view suffer because

the organisms are often highly mobile and intentionally

elusive of observers. Plant ecologists do not encounter this

ephemeral characteristic among their subjects. Plants usually

occur in greater densities than do most animals. Consequently,

ecological studies restricted to plants may be performed

easily from a community point of view.

An autecologic or population approach is admittedly one

which is narrow in scope. Many ecological parameters are

not defined. The broad view is lost. Compensation for these

weaknesses comes, however, by the elucidation of subtleties

which can be exposed by an in-depth study of a member popu-

lation of the community.

The study focused on CJL laevigata, the hackberry, as the

subject. Prior observation indicated that this tree species

occurred with high frequency in flood plain stands throughout

Denton County, Few studies until this time have revealed

this hackberry to be of major importance in the vegetational

association of flood plains. These were limited mainly to

studies of vegetation bordering the Mississippi River. The

literature contains little else regarding Cj. laevigata r

especially from an autecological point of view.

Parts of the Study

The study was divided into several parts. Most of the

work done was directed toward a comparison of the existing

structure of the population in two stands each on Denton

Creek and Elm Fork. Density and biomass were the prime

parameters of consideration. The population was sampled by

means of line transects. Individuals whose crowns inter-

cepted a transect were used as the basic study units. A more

detailed explanation is presented in Chapter IV regarding

field methods.

The dynamics of establishment and perpetuation of the

species was studied by several means. The reproductives

of the population were sampled and compared. Tree rings were

analyzed as evidence of relative growth rates. Some phono-

logical observations indicated additional variation.

In an effort to explain hypothesized variation between

streams, soils were analyzed for particle size as an indi-

cation of moisture-holding capacity. Consideration was

given to the anthropeic factor in explaining variations.

Superficial observation during the course of the study

suggested that variation of the laevigata population

could best be explained by the use which man has made of the

flood plain forests.

CHAPTER II

LITERATURE SURVEY

The literature contains several references to flood

plain community studies. Forests have been variously de-

scribed. The ash-elm association has received the most

attention in the literature. Such an association seems to be

prevalent in flood plains of the middle- and north-central

United States. Lee (1945) studied forests of this type

along the White River in Indiana. The northern hackberry,

C. occidentalis. was described as the third most important

species in the association. Blackmore and Ebinger (1967)

found a similar situation near Sycamore Creek in east-

central Illinois.

Other flood plain forests have also received attention.

Lindsey and others (1961) discussed associations along the

Wabash and Tippecanoe Rivers of Indiana. Low-level bottom-

lands (first bottoms) were dominated primarily by maple and

American elm. Northern hackberry ranked about sixth in

importance. The second bottoms, however, were dominated by

this hackberry species. The third bottoms of the Tippecanoe

River were devoid of hackberry and were dominated by basswood,

white oak, and red oak. Lindsey in 1962 presented a study of

an original forest of the Wabash flood plain in which he

found dominance shared by oak, gum, elm, and hickory. C.

occidentalis was of minor significance.

One paper was found regarding flood plain forest studies

in the eastern United States. Buell and Wistendahl (1955)

described a maple-beech-basswood association by the Raritan

River in New Jersey. Northern hackberry was mentioned as one

of the least important species.

Three studies and one descriptive article discussed the

flood plain occurrence of G. laevigata. Shelford (1954)

referred to the association of this species and sweetgum as the

stage of succession following the cottonwood-willow association

along the lower Mississippi River near Lake Reelfoot. Putnam

(1932) described this hackberry as occurring frequently in

clay flats in "first bottoms". He stated that it was limited

to the hackberry-cedar elm association, in which it was fre-

quently the predominant species. Penfound (1948), in a short

article, described C. laevigata as being of minor importance

in the elm-ash association in a flood plain stand near Norman,

Oklahoma.

The only reference to the hackberry in Texas flood plains

is by Tharp (1926), He discussed the burr oak-pecan-cedar elm

association on San Antonio River bottomlands in the southern

part of the state. The hackberry was mentioned as being fourth

in importance.

Celtid phenology is included in a limited number of

articles. Lamb (1915) indicated April 15 as the mean date

for bud break of £. occidentalis in the eastern United States.

Hulbert (1963) published Gates' phenological records spanning

a thirty-year period. Flowering of CJU occid^ntalis began

around the mean date of April 15, with a range from March 31

to Hay 10. Bonck and Penfound (1944) described twig elongation

of CJL mississjppiensis as beginning on April 7. Total

elongation averaged 38.0 cm. The study was made in 1943 along

the Mississippi River near its mouth. Eggler (1955) studied

radial growth of several tree species near New Orleans, He

reported a 3.9 mm. average increase for ten laevigata

trees during 1952,

References regarding Denton County include articles and

personal interviews with individuals who have lived in the

locality since the early 1900*s. The United States Secretary

of Agriculture's report (1942) of the Trinity River watershed

briefly described the "dark clay-textured soils" of the

county. No details of the vegetation structure in the flood

plains were given. Carter and Beck (1922) discussed Frio and

Lewisville clays as occurring frequently along Denton Creek

and Elm Fork.

Cowling (1922), discussing the use of flood plain trees,

mentioned that hackberry and other timber were used for "log

huts and clap-board roofs." Interviews with Laura Heath and

Hubert Wright of Roanoke and M. L. Swafford of Ponder indi-

cated that timber-cutting for both fuel and lumber purposes

was common around Denton Creek prior to the 1930's. Vegetation

zone maps from Carter and Beck (1922) and from the Trinity

8

River watershed report showed the Grand Prairie enclosing

Denton Creek, Elm Fork was bordered by the Grand Prairie

and the eastern cross timbers. In the cross timbers fuel was

more readily obtained than around Denton Creek, where the

flood plains contained the primary fuel supply.

Some references pertained to techniques and methods used

in the study. Basic information regarding basal area measure-

ment and the line intercept sampling method were obtained from

Phillips (1959). Various areal and line transect sampling

methods were studied and compared by Buell and Cantlon (1950),

Lindsey et al, (1958), and Berry (1962).

CHAPTER BIBLIOGRAPHY !

Berry, Brian J. L. 1962. Sampling, coding, and storing flood plain data. U. S, Dept. Agric. Agric. Handbook 239: 1-27,

Blackmore, B, K, 1967, Vegetation survey of Burgner Acres, East-Central Illinois. 111. State Acad. Sci. Trans, 60: 72-79,

Bonck, J,, and W, T, Penfound. 1944, Seasonal growth of twigs of trees in the batture lands of the New Orleans area. Ecology 25: 473-475,

Buell, M. F., and J. E. Cantlon. 1950. A study of two com-munities of the New Jersey pine barrens and a comparison of methods. Ecology 31: 567-568.

Carter, W. T., and M. W. Beck. 1922. Soil Survey of Denton County, Texas. U. S. Dept. of Agric. Govt; Printing Office, Washington. 58 p.

Cowling, H. J. 1936. Geography of Denton County, Banks Upshaw and Co,, Dallas, 132 p.

Eggler, W. A, 1955, Radial growth in nine species.of trees in southern-'Louisiana. Ecology 36: 130-136,

Heath, Laura. 1969. Personal interview. 5 Aug. Roanoke, Texas.

Hulbert, L. C. 1963. Gates* phenological records of 132 plants at Manhatten, Kansas. 1926-1955. Kansas Acad, Sci. Trans. 66i 82-106.

Lamb, G. N. 1915. A calendar of the leafing, flowering and seeding of the common trees for the eastern United States. Monthly Weather Rev. Supp. No. 2: 5-19.

Lee, Mordie B. 1945. An ecological study of the flood-plain forest along the White River system in Indiana. Butler Univ. Bot. Stud. 7: 155-175.

Lindsey, Alton A, 1962. Analysis of an original forest of the lower Wabash floodplain and upland. Indiana Acad. Sci. Proc. 72: 282-287.

Lindsey, A, A., J. D. Barton, and S. R. Miles. 1958. Field efficiencies of forest sampling methods. Ecology 39: 428-444.

Lindsey, A. A., R. O. Petty, D. K. Sterling, and W. Van Asdall. 1961. Vegetation and environment along the Wabash and Tippecanoe Rivers. Ecol. Monogr. 31: 105-156.

Penfound, W. T. 1948. An analysis of an elm-ash floodplain community near Norman, Oklahoma. Okla. Acad. Sci. Proc. 28:56-60 . 51-kO'

Phillips, E. A. 1959. Methods of vegetation study. Holt, Rinehart and Winston, Inc., New York. 107 p.

Putnam, J. A., and H. Bull. 1932. The trees of the bottom-lands of the Mississippi River delta region. Southern Forest Expt. Sta., Occ. Paper 27: 1-207.

The Secretary of Agriculture. 1942. Survey report of the Trinity River watershed. Seventy-seventh Congress, Second Session. House Doc. No. 708: 66 p.

Shelford, V. E. 1954* Some lower Mississippi valley flood plain biotic communities; their age and elevation. Ecology 35: 126-142,

Swafford, M, L, 1969, Personal interview, 5 Aug, Ponder, Texas,

Tharp, B, C, 1926, Structure of Texas vegetation east of the 98th meridian. Univ. Tex. Bull, No, 2606, 97 p,

Wright, Hubert, 1969, Personal interview, 5 Aug, Roanoke, Texas,

CHAPTER III

STUDY AREA

Selection of stands for sampling involved consideration

of three main criteria. The first of these was size of the

stand. Each stand had to be large enough to accommodate the

line transects used for sampling and to avoid ecotone effects.

The second, closely related to the first, was the homogeneity

of vegetation within a given stand. The greater the uni-

formity, the lower would be the amount of error due to

sampling. Finally, more than one stand per stream was needed

in order to determine the amount of variation existing within

stands along the same stream. An attempt was made to insure

adequate and comparable spacing of the stands on each stream.

To locate stands for sampling, aerial photographs of

Denton County were examined in the Agricultural Stabilization

and Control Office in Denton, From these maps five stands —

three on Denton Creek and two on Elm Fork — were chosen for

reconnaissance, A stand on Denton Creek south of Stony proved

to be too heterogeneous for inclusion into the study. This

stand was irregularly divided by fenceline because it was not

under single ownership. Several head of cattle were being run

in the south part. For some reason, the density of hackberry

trees north of the fenceline was over five times greater than

the density on the other side of the fence.

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Four stands, two each on Denton Creek and Elm Fork, were

subsequently studied. The two stands on one stream were coded

as upper and lower. Coordinates of geographic location of

each stand are given in Table 1.

TABLE I

GEOGRAPHIC COORDINATES OF FLOOD PLAIN FORESTS STUDIED

Stand Latitude Longitude

Lower Denton Creek 33° 02.0' N 97° 14.5' W

Upper Denton Creek 33° 08.5« N 97° 20.0' W

Lower Elm Fork 33° 17.0' N 97° 02.5' W

Upper Elm Fork 33° 23.0' N 97° 05.5' W

Maps of north-central and south-west Denton County (Figure l)

show the location of the stands in relation to nearby towns,

streams, and major roads.

The lower Denton Creek stand, two miles north of Roanoke,

is presently included in the Grapevine reservoir recreational

area. The property has been owned jointly by A. L. Slaughter

heirs and the government since 1940 (Denton County Courthouse

Records, 1969). Prior ownership was by Degan and Raley, from

1929. Earlier records were unav&ilable. The stand covers

approximately 206 acres. The stand was sampled in the north-

west part because of its accessibility and apparent uniformity,

13

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14

Transects were laid at 180°, 135°, and 105°, from a single base

point, a large honey locust tree approximately 430 meters south

of the bridge which crosses the stream near the north end of

the stand, and 140 meters east of the gravel road. Figure 2

shows a typical view in this stand. An aerial photograph of

the stand is shown in Figure 3.

The forest coded as upper Denton Greek is privately owned

by the heirs of T. A. Swafford, who purchased the land in 1903.

It is located about 4 miles southwest of Ponder. The stand is

much smaller than the lower Denton Creek stand, covering about

22 acres. Isolated from roads, the stand was accessible

through the dairy farm operated by Sam Teal. Two transects

were laid at 180° and 205° from a common base. The base tree

was a large Shumard oak 50 meters west of the north-east corner

of the stand and 30 meters south from the north fence line.

The second transect changed from 205° to a 135° bearing when

it approached Denton Creek. The third transect was laid at 0°

from a large American elm 50 meters north of the southernmost

projection of the stand. Figure 4 shows an aerial view of the

upper Denton Creek location.

The lower Elm Fork stand has been owned by the City of

Dallas since 1925, and is under the jurisdiction of the Army

Corps of Engineers. Lying about 7 miles north-east of down-

town Denton, this flood plain forest stand covers about 240

acres. It is continuous by means of a narrow wooded strip

with a similar-sized stand immediately to the south-west.

15

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16

Fig. 4 — Aerial view of upper Denton Creek stand. 1 in. = 660 ft.

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18

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Fig. 6 — Aerial view of the upper Elm Fork stand. 1 in. = 660 ft.

19

Access to the stand was gained by crossing a large field to

the west of the stand. A shallow temporary creek cuts south

along the western edge of the stand. Three transects were

angled from one base point, a large cedar elm tree 280 meters

south of the north fence and 30 meters east of the west fence.

Transects were laid at 160°, 110°, and 70°. An aerial view of

the lower Elm Fork stand is shown in figure 5.

The upper Elm Fork stand is centrally located near the

north county line. Courthouse records listed J. P.. Tomkins

as owner since 1938, preceeded by A. 0. Mason. The relatively

small 24-acre stand lies about 5 miles east of Sanger and just

north of farm-to-market road 455. A field and a very deep

creek gully had to be crossed to get to the stand from the

south. Three north-south transects were laid out. from dif-

ferent base points. The east transect started from an

exceptionally large burr oak tree in the north-east part of

the stand. The central and west transects began from large

cedar elms in the south part of the stand. Figure 6 is an

aerial view of this stand.

All of the stands studied lie in what would be called the

second bottom or the upper part of the first bottom. Such

lands typically are subject to infrequent overflow and are

"covered by heavy, luxuriant hardwood forests" (Tharp, 1926).

During the spring of 1969, Denton Creek overflowed the lower

stand and a wide low area of the upper stand only once. The

upper Elm Fork stand was not flooded during the study.

20

Because of the proximity of the Shallow creek, however, th©

sampling area of the lower stand on Elm Fork was inundated

several times. In all cases the period of submergence of the

land was probably for no more than a few hours, and then only

to a shallow depth. The four stands were all located on flat,

poorly-drained land. Following rains and especially after

floods, numerous temporary pools of stagnant water remained.

The pools, being of different depths, lasted from several days

to a few months.

Soils in the four stands seemed to show little difference

in color, texture, or composition. Both the A^ and the Bi layers

were composed of dark gray-brown fine soil which was predomin-

antly clay. Data and analysis of the soils are presented in

Chapter V.

The herbaceous and frutescent layers of vegetation were

very similar between most of the stands. Patches of greenbriar

bramble, deep grass, and coralberry thicket were encountered.

The Denton Creek stands and lower Elm Fork had fairly dense

crown covers produced by 35- to 50-feet-tall trees. This 1 .

resulted in less of the thick weed and grass ground cover.

The upper Elm Fork stand, though was characterized by large

and tall but sparse trees (figure 6). More light penetrated to

the ground there, and consequently the ground cover was much

denser. Less greenbriar occurred in this stand, but the

coralberry thickets were much more extensive and well-developed.

An important characteristic of all of the stands as far as

21

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22

this study was concerned was the lack of extensive recent

destruction of the vegetation. Only infrequent cattle-

grazing was noted. This occurred only in the Denton Creek

stands. These may have been incidents of. a few cattle

crossing through a break in a fence. Overall, the four

forest stands studied appeared relatively undisturbed,

CHAPTER BIBLIOGRAPHY

Denton County Courthouse Records, 1969, Denton County Land Ownerships, Denton, Texas,

Tharp, B, C, 1926, Structure of Texas vegetation east of the 98th meridian, Univ. Tex, Bull, No, 2606, 97 p.

r -

CHAFTER IV

METHODOLOGY

Intercept Transect for Sampling Mature Trees

To achieve adequate and balanced sampling within stands,

three transects were spaced to cover a wide area. Effort was

exerted to avoid ecotones and ecologically unusual pockets

of vegetation within the stands. Transects were laid out with

the use of a pocket compass which was accurate within about

five degrees. Trees lying on the transects were marked with

a double band of masking tape near eye level. Hackberry trees

that had crowns which intercepted the transect received a

single band. Trees were coded by transect and assigned

numbers from one through fifty. Diameter breast high of each

hackberry was measured with a standard diameter tape. Tree

heights were estimated as accurately as possible without the

use of a direct measuring device.

The length of each transect was arbitrarily set as the

distance required to intercept the crowns of 50 hackberry

trees having trunk diameters of 1% inch or more. Transect

length was estimated by pacing. An attempt was made to make

paces consistently as close to 1 meter length as possible

without actual tape measure,

23

24

For measuring the lateral growth of the tree trunk, cross-

section cuts were made. Sections were returned to the labora-

tory, where they were sanded smooth on one surface. Rings were

counted and measurements were made with the aid of a dissecting

scope

Belt Transect for Sampling Reproductives

Hackberry plants smaller than 1% inches diameter breast

high were considered reproductives and subjected to a belt

transect sampling procedure. The transect size was 1 meter

wide by 100 meters long. Belt transects were laid along the

right side of each line transect and were placed so that

they would not be close to one another. They were run through

areas having roughly equal quantities of high and low mature

hackberry density. Figures 8 through 11 in Chapter V include

the locations of the reproductive transects. The letter "a"

indicates where the transect began and the letter "b", where

it terminated.

During the investigation, it became apparent that grouping

all reproductives together was less than adequate. The

decision was made to divide the young plants into three sub-

classes, These were seedlings, plants from 2 years old to

1 meter high, and those from 1 meter high to 1% inches diameter

breast high. Seedlings were very numerous but also showed a

high mortality rate. After the first year, the main compe-

tition comes mainly from dense herbaceous and low frutescent

layer growth. Above one meter height, competition is limited

mainly to the tree crowns forming the forest canopy. Data and

discussion in the next chapter demonstrate the value of such

a dividing of the reproductive class.

Phenology

The phenology of the hackberry was studied to a limited

extent. Extensive rains and other conflicts prevented regular

observations of all of the flood plain stands used in the

study. The factors considered were bud break, flowering,

leafing,and fruiting. Observations were made from March

through May of 1969. The set of phenological data is pre-

sented in Chapter V.

Soils

Soil samples were collected with a cylindrical auger.

In preparing to take the sample, surface litter was first

cleared away. The top few inches were sampled as the

layer. About 6 to 10 inches down, the soil texture became

finer and the soil was more compact. Samples at this depth

were considered to be from the layer. In the laboratory,

the samples were dried for at least 24 hours at 110° C.

Fifty-gram samples were mixed with 5 milliliters of 1 normal

sodium hydroxide and 5 milliliters of sodium oxalate solution.

This was allowed to soak for 15 minutes, then the mixture was

blended in a malt blender for 10 minutes. The suspension was

then mixed with distilled water to form a volume of 1 liter.

Density of the solution was measured at 40 seconds, 50

minutes,and 2 hours,with a Bouyoucos hydrometer calibrated in

26

grams of suspended soil particles per liter of suspension.

Bouyoucos (1930) indicated that sands settle out before

40 seconds and that total colloids (clay and fine silt up

to about .008 millimeter particle diameter) remain suspended

after 15 minutes. Only fine clays (.002 millimeter) remain

at 2 hours. Bouyoucos stated that the wilting coefficient

may be obtained by multiplying per cent total colloids by

.2835. Moisture equivalent is derived by multiplying the same

figure by .6515. Data regarding flood plain soil samples are

considered in the next chapter, ,

CHAPTER BIBLIOGRAPHY

Bouyoucos, G. J. 1930. The indirect determination of various soil characteristics by the hydrometer method. Soil Sci. 30:267-272.

CHAPTER V

RESULTS

Statistical Treatment of the Data

Variation was encountered between individual trees,

transects within single stands, stands on the same stream,

and between streams. To accurately attribute variation to

the proper level, the F test was used to indicate whether or

not real differences existed in various parameters of the

populations studied.

Table II summarizes the analysis of variance for balanced

repeated subsampling. This form was adaptable to the design

of the investigation. Denton Creek and Elm Fork, the streams

compared, represented the A class. Small letters in the table

symbolize the number of components in a given class; in this

study, "a" equaled two. The B subclasses within A were the

two stands on each stream. The C sub-subclasses within B

were the three transects per stand. The fifty trees measured

in each transect constituted the basic observations; "y"

symbolizes the value of each observation^ and "r" represents

the number of observations. Explanations of other symbols used

in Table II include the following: DF-— degrees of freedom;

S S — sum of squares; MS — mean square; T — total for a given

class; N—» total number of observations in the experiment;

C m — correction of the mean.

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W II cd i s a

S a II C/3 i a •

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it)

w » O w t *4 E

U 1 <J) 6 o u k *0 a J2 v u c II

^ ^ n4 i CM CM CM cd a

a b c m

CM N H H H CD fcs CM

H

/ %

r4 ^4 *~4 t-l rl H t i l l 1

fc* a b c r & w v-/ cd o

cd *o cd

CO a a <5 « o c o £ CO *rl o •H (U a) d a w •H 4J <D CO «rl «rl Cd 4~> cd & CO «C «Xh ^ U •r-l 4J Cd ^ u r-4 0) k 0) rM »H <D Cd k cdCQ O J 3 01 P k > ,0 0 o < 03 U O H O

E # < 3 E # • • £ N i

A

B

C

R

o

VD ON

* CO CO

m e o u \sa

29

Population Parameters of Density

Densities of the hackberry populations were measured by

the lengths of transects, which contained fifty trees each.

The mean density was assumed to be inversely proportional to

the transect length. Table III lists the lengths of the tran-

sects in the study and the analysis of variance of these data.

TABLE III

LENGTHS OF TRANSECTS CONTAINING FIFTY HACKBERRY TREES

Stand Transect Denton Creek Elm Fork

Lower A 312 m. 263 m.

B 261 234

C 249 195

Upper A 171 349

B 168 340

C 131 287

ANALYSIS OF VARIANCE

Source of Variation

DF SS MS F

Streams 1 11,782 11,782 0.69 n.s.

Stands 2 34,093 17,047 17.5 **

Transects 8 979

!;•'

30

Significance levels in this and other tables aire indicated

in the following ways. If the probability of a real difference

was not at least 95 per cent (Bliss, 1967), the F value was

declared not significant and indicated by "n.s." A 95 per

cent probability of a real difference was accepted as signi-

ficant and indicated by an asterisk (*); a probability ex-

ceeding 99 per cent (highly significant) was indicated by a

double asterisk (**).

Analysis of variance for the data in Table III showed very

little difference attributable to variations between streams.

Transect lengths within stands were more or less uniform.

Highly significant difference existed between stands, however.

Inspection of the data indicates short transect lengths in

the upper Denton Creek stand and long transects in the upper

Elm Fork.

Raw data regarding individual tree location on the tran-

sects were translated into maps. Figures,8 through 11 show

transect locations in stands and where trees occurred along

these transects. Transect data from which the maps were

produced are included in the Appendix, Section A, Locations

were defined to the nearest meter. Distance from the base

and lateral distance from the transect line were recorded for

each tree.

Most transects were characterized by localized variations

of hackberry density. Typical distribution patterns included

two or three main clusters of hackberry trees per transect.

I

• *. • •

k •

• . C V

31

H A

w

* •••J # . . . a i'^Vi

v *

• t k . .

%

•• — C

%

Om. Lmm

SO i 100 mmmJ

Fig. 8 -- Hap showing locations of hackberry trees sampled in the lower Denton Creek stand* Codes for symbols may be found on page 35.

32

Fig. 9 — Map showing locations of hackberry trees sampled in the upper Denton Creek stand. Codes for symbols may be found on page 35.

33

N A

0 * *•

• 1.1 • • * •

• • A • % •# •

«tk • I I ••• •

f •

* » • ? :

• • b « v

n

## • # #

2>P

O m. Lm

Scale SO . I

too — J

• • ' •

Fig. 10 — Map showing locations of hackberry trees sampled in the lower Elm Fork stand. Codes for symbols may be found on page 35.

34

\

Fig. 11 n.m Map showing locations of hackberry trees sampled in the upper Elm Fork stand. Codes for symbols may be found on page 35

35

The clusters were separated by rather distinct sparse zones.

Extremes in clustering are illustrated by maps of upper Denton

Creek transects. Transect B shows a strong clustering pattern

while transect C demonstrates a relatively even pattern of

hackberry tree distribution.

Other pertinent transect information was recorded on the

maps. Dashes followed by the letter "C" indicate locations of

clearings, the lengths of which were discounted from the total

transect lengths. The letter "P" with a dash represents stag-

nant water pools in which no trees grew. Small letters "a"

and MbM were used respectively to show the beginning and end

of the reproductive transects. An "x" indicates where soil

samples were taken.

Population Parameters of Biomass

Diameter Breast High Size Distribution

Phillips (1959) stated that "area covered by tree trunks

at 4.5 feet from the ground (breast height, the height at

which diameters are taken in American forestry)... givesa

good estimate of the relative importance of trees on a cover

basis.1' Cross-sectional areas were derived from measurements

of diameter breast high. Graphs of the distribution of

diameter sizes of trees in stands provides a basis for com-

parison, Figures 12 through 15 show these graphs. The graphs

reveal rather definite patterns regarding size distribution

within the populations. Certain similarities among all four

graphs suggest a periodic phenomenon. For example, peaks may

36

Number of

Trees

Dia- . . . . 5 . . . . 10 . . . . 15 . . . . 20 . . . . 25 - over meter (in.)

Fig. 12 — Size distribution of hackberry trees in lower Denton Creek stand.

Number of

Trees

20

15 _

10 _

0 Dia- . . . . 5 . . . . 1 0 . . . . 1 5

meter (in.) 20 * • • • 25 - over

Fig. 13 — Size distribution of hackberry trees in upper Denton Creek stand.

37

Number of

Trees

Dia- . . . . 5 . . . . 10 . . . . 15 . . . . 20 . . . . 25 - over meter (in.)

Fig. 14 — Size distribution of hackberry trees in lower Elm Fork stand.

Number of

Trees

Dia- . . . • 5 . . . . 10 meter (in.)

• • 9 # 15 . . . .20 • 4» • 25 - over

Fig. 15 — Size distribution of hackberry trees in upper Elm Fork stand.

38 (s, L

be noted in all of the graphs for the 4- and 6-inch diameter

sizes. If this is accurate, conditions favorable to repro-

ductive establishment occurred somewhat periodically. Such

conditions probably involved sufficient moisture, but with-

out serious flooding.

Observation of general trends in the graphs indicates

what may be important differences among the stands. The

lower Denton Creek graph (Figure 12) illustrates a prepon-

derance of small trees, mostly 6 inches and less in diameter.

The upper Denton Creek hackberry population is dominated by

the 2- to 8-inch size range. The range from 3 to 12 inches

accounts for most of the lower Elm Fork hackberry trees. The

4- to 14-inch range in the upper Elm Fork stand contains the

bulk of the hackberry trees there.

The size distributions noted suggest that succession is

occurring in the Denton County flood plain forests. If the

trends indicated by the graphs are correct for the entire

population in each stand, the conclusion may be drawn that

the lower Denton Creek stand is the ecologically youngest

forest of the four. At the other end of the succession

spectrum is the upper Elm Fork stand, ecologically the closest

to the climax state.

If the vegetation was in a stable phase of succession,

however, Figure 12 indicates that mature trees of the lower

Denton Creek stand were susceptible to some limiting factor

or complex of factors. Such a factor is timber-cutting by

man. The only indication that this may have occurred was

39

the presence of a grown-over, one-lane dirt road which

passed through part of the sampling area. No stumps were

observed, thus indicating that timber had not been cut

recently.

Figure 13 does not show a sharp decrease in tree numbers

until the eight-inch size is reached. This may correspond

with the years around 1930 when butane and gas fuels were

first used in place of wood in Denton County.(Swafford, 1969).

One other important factor may be noted in figure 15.

Over three times as many trees above 15 inches diameter were

found in the upper Elm Fork stand as in all of the other

stands combined. These trees were taller by 20 feet or more

than trees in the other stands. Large diameter size and

height were also noted^for other species such as cedar elm

and burr oak. The only theory postulated to explain this

phenomenon is that this represents a higher level of suc-

cession than that found in the other stands.

An unusually large hackberry tree was intercepted by

transect C in the lower Elm Fork stand. This tree had a

diameter of 31 inches. Laughlin (1947) listed 29.5 inches

as the maximum diameter for C,,. laevigata. A photograph of

the tree is shown in figure 16. Dividing the diameter by

the mean growth rate which was determined for the lower

EUm Fork stand resulted in an age of 262 years — dating

the tree back to 1706,

40

• « : % *

K.xJfEX

mwm ty- H- :.- . V i vvift

H W

'2? J B B K M

Fig. 16 -- View of the largest of all trees sampled - a 31-inch diameter breast high hackberry found in transect C in the lower Elm Fork stand.

41

The next two largest trees encountered in the study were

23.5 inches (upper Elm Fork, transect A) and 20^5 inches

(lower Elm Fork, transect C) in diameter. The largest trees

in the Denton Creek stands were two 15-inch trees, one in

each stand.

To correctly interpret graphs in Figures 12 through 15,

a factor introduced by the sampling method should be con-

sidered. Small trees had small crowns. Therefore they had

to grow somewhat close to the transect line in order to be

included in the sample. Proportionally fewer small trees

Number of

Trees

Dia- . . . . 5 meter (in.)

10 15 20 25 - over

Fig. 17 — Diameter breast high for 600 hackberry trees sampled by intercept transects.

42

than large ones were intercepted. Figure 17 shows the dia-

meter breast high distribution for all 600 hackberry trees

measured.

-- Tfcees in the range from 1% to 3 inches were incurred less

often than had been expected. This is due primarily to the

sampling method. A plot or areal method probably would not

produce this result, especially if it is a real sampling

error. The advantage of the line transect method which

resulted in its use in this study was the short time required

and the facility of covering the sampling area.

Basal Area

As an indicator of biomass, basal area was calculated for

each of the 600 trees sampled. Transect totals for the data

are shown in Table IV along with the analysis of variance.

TABLE IV

HACKBERRY BASAL AREA TOTALS — 50-TREE TRANSECTS

Stand Transect Denton Creek Elm Fork

Lower A 858 in.2 2286 in.2

B 1297 2483

C 1754 3193

Upper A 945 4802

B 1495 3974

C 1918 3515

43

TABLE IV — Continued

•ANALYSIS OF VARIANCE

Source of Variation DF SS MS F

Streams 1 239,454 239*454 7.59 n.s.

Stands 2 63,121 31,561 5.78 *

Transects 8 43,693 5,462 3.29 **

Trees 588 1,952,467 1,660

Total basal area of the sampling on Denton Creek stands

was 8,267 square inches, while that for Elm Fork was 20,252

square inches. Although these values are wide apart, no

difference was demonstrated between streams. This was due

mainly to the low number of degrees of freedom. The F value

indicating difference at the 5 per cent level is 18.5 when

numerator and denominator degrees of freedom are 1 and 2,

respectively. The data were such, however,as to show signi-

ficant difference between stands and highly significant

difference between transects. Further tests would be required

to pinpoint which stands and which transects varied signi-

ficantly from the population bulk.

Basal Area Density

Since hackberry basal area totals were demonstrated not

to be different between streams, the question was asked if

interaction of basal area and density would produce other

results. Such a biomass density would be a better measure

44

of the extent to which conditions allow a species to develop

than individual density would be. Accepted units of square

inches for basal area and meters for transect length resulted

in the unit of square inches per meter for the basal area

density. Table V contains the derived data and the analysis

of variance,

TABLE V

HACKBERRY BASAL AREA DENSITY

Stand Transect Denton Creek Elm Fork

Lower A 2.75 in2/m 8.69 in^/m

B 4.97 10.61

C 7.04 16.37

Upper A 5.53 13.76

B 8.90 11.69

C 14.64 12.25

ANALYSIS OF VARIANCE

Source of Variation

DF SS MS F

Streams 1 72.7 72.7 4.18 n.s.

Stands 2 34.8 17.4 1.63 n.s.

Transects 8 85.9 10.7

45

Although considerable variation appeared to exist, the

diversity of the data allowed no difference at either the

stream or stand level. Therefore, in this case, no bioraass

density variations were clearly evident.

Tree Height

As an added means of measuring biomass, consideration

was given to the parameter of height. Variations were

observed between stands. Average tree height ranged from

27.1 feet in the lower Denton Creek stand to 38.4 feet in

the upper Elm Fork stand. Average tree heights per transect

and the analysis of variance are given in Table VI.

TABLE VI

AVERAGE TREE HEIGHT PER TRANSECT

Stand Transect Denton Creek Elm Fork

Lower A 23.2 ft 29.2 ft

B 26.8 32.5

C 31.2 30.8

Upper A 30.1 38.1

B 32.9 38.2

C 34.2 38.8

46

TABLE VI — Continued

ANALYSIS OF VARIANCE

Source of Variation DF SS MS F

Streams 1 72.6 72.6 1.14 n.s.

Stands 2 126.3 63.2 10.9 **

Transects 8 46.6 5.82

No difference was demonstrated between stream populations,

Variation between stands was sufficient to result in highly

significant difference at this particular level. This may be

understood by noting that very little variation occurred with-

in stands. Thus a very low mean square value resulted at the

transect level. When divided into the mean square between

stands, the F value was highly significant.

An Observation

Before leaving the topic of biomass parameters, a pattern

occurring between stands and repeating within the different

parameters may be noted. Table VII contains the stand totals

for data studied in this section of the thesis. Values in-

crease in the progression from the lower Denton Creek stand

to upper Denton Creek, to lower Elm Fork, and finally to the

upper Elm Fork stand. This is the same progression which was

postulated regarding succession. Only one exception to the

pattern occurred — between the upper Denton Creek and the

lower Elm Fork totals for average tree height. Analysis

47

TABLE VII

STAND TOTALS FOR BIOMASS PARAMETERS -NUMERICAL VALUES ONLY

Parameter LDC Stand

UDC LEF UEF

Basal Area 3,909 4,358 7,962 12,291

Basal Area Density 14.76 29.07 35.67 37.70

Tree Height 81.2 97.2 92.5 115.1

of correlation would be needed to demonstrate the extent of

reliability of the consistency which appears. Such a pro-

cedure was not performed during the course of this study.

Community Parameters

Per Cent of Total Tree Density

Other trees which intercepted the transects were counted

so that percentage of total tree density attributable to

hackberry might be calculated. The values obtained are con-

tained in Table VIII with the analysis of variance. (

The F values indicate no difference between streams for

the factor under consideration. It may be noted, though,

that all values but one among all of the Elm Fork transects

were consistent. Nevertheless, sufficient variation existed

between stands, expecially on Denton Creek, to result in a

significant F for the comparison between stands. Lower Denton

Creek percentages were low because of many cedar elms there.

48

TABLE VIII

PER CENT OF TOTAL TREE DENSITY REPRESENTED BY HACKBERRY

Stand Transect Denton Creek Elm Fork

Lower A

B

C

30.3 %

22.3

29.1

58.1 %

61.7

59.5

Upper A

B

C

34.7

43.9

53.9

57.3

50.5

57.3

A M iLYSIS OF VARIANCE

Source of Variation DF SS MS F

Streams

Stands

Transects

1

2

8

I4I2.7

463.7

259.1

1412.7

231.9

32.4

6.09 n.s.

7.16 *

Per Cent of Total Basal Area

Besides counting th$ trees of other species intercepting

the transects, the diameter breast high was measured to the

nearest inch for each tree. This set of data is recorded in

Section B of the Appendix. From the diameters, basal area was

figured and totaled for each transect. The percentage of

49

total basal area represented by hackberry was calculated.

Table IX contains these percentages and the analysis of

variance of the data.

TABLE IX

PER CENT BASAL AREA ATTRIBUTABLE TO HACKBERRY

Stand Transect Denton Creek Elm Fork

Lower A 13 % 42 %

B 17 41

C 31 42

Upper A 19 39

B 36 41

C 23 31

ANALYSIS OF VARIANCE

Source of Variation DF SS MS F

Streams 1 784 784 19.1 *

Stands 2 31 41 0.84 n.s.

Transects 8 393 49

As the analysis of variance indicates, difference at the

5 per cent level of probability existed between streams.

This means that samplings from a random population would

result in a greater F value in fewer than 5 per cent of all

such cases. This was the only set of data in the investigation

50

which attributed significant difference to the conditions

existing in the flood plain stands between Denton Creek and

Elm Fork.

Observation of the data in Table IX indicates that the

hackberry population in the Elm Fork stands accounts for

about 40 per cent of the total basal area in the stands.

This parallels the conclusion about the stage of succession

which the stands are going through. As a species is being

replaced, individuals of that species grow large, but their

reproduction diminishes. Under this condition the species

retains a considerable portion of the basal area total.

Tree Ring Study

To obtain further information regarding the success of

the hackberry population in different stands, trunk cross-

sections of twenty-four trees were cut. The amounts of

radial growth for the twelve-year period from 1957 through

1968 were measured and compared between trees, stands and

streams. The segment thicknesses for each tree studied are

listed in Table X.

The analysis of variance shows no difference at either

the stream or stand level. Wide variation between trees

probably was the cause of the statistical results. Average

tree-ring width ranged from 0.59 to 4.94 millimeters per

annulus. Mean width for Denton Creek trees sampled is 2.36

millimeters while only 1.34 millimeters for Elm Fork trees.

These values indicate that trees along Denton Creek were

51

TABLE X

TWELVE-YEAR TREE-RING SEGMENT THICKNESS

Stand Tree Thickness Stand Tree Thickness

Lower A- 2 24.2 mm Lower • A- 9 10.2 mm Denton A-14 10.7 Elm A-22 24.3 Creek B- 3 39.7 Fork B-33 7.1

B- 7 19.0 B-38 9.6 C- 3 21.9 C-23 25.7 C-15 34.6 C-38 29.9

Upper A-11 9.9 Upper A-21 13.9 Denton A-24 59.3 Elm A-44 17.1 Creek B- 5 17.0 Fork B-12 10.5

B-17 23.0 B-23 7.4 C-37 46.0 C-10 21.2 C-46 35.7 C-40 26.7

ANALYSIS OF VARIANCE

Source of Variation DF SS MS F

Streams 1 5.46 5.46 10.5 n.s.

Stands 2 1.03 0.52 0.37 n.s.

Trees 20 28.08 1.40

growing at almost double the rate of trees along Elm Fork.

Such a growth rate was unexpected because average Denton Creek

tree size was about half of the average Elm Fork size. An

explanation for this phenomenon is that overstory competition

may have inhibited growth of the sample trees which were from

three to six inches in diameter breast high. Factors of suc-

cession may account for this slow-down in radial growth.

52

Reproductive Study

Data regarding reproductive plant counts and transects

are included in Table XI. Three conclusions can be drawn

from these data. First, the sampling units were too small to

obtain sufficient information, especially regarding post-

seedling reproductives. Secondly, the sampling technique

lacked precision. Finally, a high mortality rate existed

during the seedling stage.

The data for reproductive class III in the lower Denton

Creek stand show wide variation. Reliability of these data

is consequently very low. An increased sampling area would

provide more uniformity among results.

Regarding the precision of the sampling, the techniques

used resulted in a lack of reproducibility. Repetition of

sampling in classes II and III of all upper Elm Fork tran-

sects and of transect C at upper Denton Creek resulted in only

one unchanged datum out of eight. The lack of precision

was due to the inexact manner of laying out the belt transects.

To gain precision in sampling, the limits of the transect

should be accurately defined, and plants should be carefully

counted. These extended efforts, however, would require much

more time than that which was expended.

The number of plants in each reproductive class was

generally lower by about half in the Elm Fork stands than in *

the Denton Creek stands. The numbers of seedlings were

significantly greater than the numbers in the other classes.

53

TABLE XI

HACKBERRY REPRODUCTIVESa

Stand and Date'3 Reproduc tive Classc

IVf 4"*« 45* Q Transect Transect

Date'3

I II III ri£li»UF©S Base®

Lower Denton

A 29 May 30 7 10 22 0 m.

Creek B 29 May 30 7 0 16 70

C 29 May 40 11 2 32 100

Upper Denton

A 30 May 41 9 6 29 0

Creek B 30 May 8 6 10 21 50

C 4 May 508 8 6 35 0

C 30 May 70f 0 8 6 35 0

Lower Elm Fork

A 30 May o h 9 1 17 0 Lower Elm Fork B 30 May 4 301

1 33 0

C 30 May 8 50 2 25 50

Upper Elm

A 23 Apr 83 2 2 13 0

Fork A 31 May 18 6 4 13 0

B 25 Apr 41 / '

4 0 7 50

B 31 May w 7 6 7 50

C 25 Apr 42 7 4 24 187

C 31 May 7 2 1 24 187

a Numbers of young hackberry plants occurring in belt

transects (100 x 1 m.) lying along one side of the intercept tiTwiiniSc trs 0

1969 sampling date.

54

TABLE XI, Continued

c Three size classes of reproductives: I - seedlings; II - 2 years old to 1 m. high; III - 1 m. high to 1% inches diameter breast high.

^ Number of mature hackberry trees whose crowns inter-cepted the reproductive belt transect.

e Distance of base of reproductive belt transect from base of intercept transect.

^ Host were very young seedlings; area showed signs of disturbance by flood, armadillos and cattle.

^ Variation from above dat;um probably due to sampling error. Other examples of such discrepancies may be noted in the upper Elm Fork data in this table.

In Low area subject to frequent flooding; no seedlings of

any woody plant species observed.

* More than half of these appeared to be 2 years old.

Samples repeated after a one-month break indicated a drop

from 1/3 to 1/7 of the original number of seedlings. This

pattern indicates a very narrow ecological amplitude of the

seedlings. The high mortality rate is obviously offset by

a high rate of viable seed production in order to make the

hackberry as dominant^ it is in the flood plain forests.

Phenology

Seasonal factors such as bud break, flowering, leafing,

and fruiting were observed irregularly during the spring of

1969. General observations £r* recorded in Table XII and

specific ones in Table XIII.

From observations noted, the phenological developments

for the lower stands on Denton Creek and Elm Fork were as

55

TABLE XII

GENERAL OBSERVATIONS REGARDING HACKBERRY PHENOLOGY

Stand 1969 Date

Observation

Lower Elm Fork

18 Mar

20 Mar

Buds slightly swollen in tree tops.

Further bud swelling on exposed limbs.

22 Mar No significant bud break.

27 Mar Buds in most tree tops swollen to one-fourth inch long

Upper Elm Fork

31 May All transect trees in full foliage.

follows: buds broke during the last week of March and the

first week of April; leaves opened during the first week of

April; flowers developed around the end of the first week of

April; fruit development was initiated during the middle of

April, An unexplained phenomenon occurred in the upper Elm

Fork stand. When visited on 1 Hay, 1969, only nineteen trees

out of 150 had any foliage at all. Of these, nine had more

or less normal foliation. One month later (31 May), all of the

sampled trees were in full foliage which was apparently

healthy. No explanation for this delay in phenological

development could be ascertained. Another factor noted during

casual observation was that the flood plain hackberry trees

set little fruit, much less than what is common in isolated

hackberry trees around Denton,

56

TABLE XIII

NUMBER OF HACKBERRY TREES PER TRANSECT EXHIBITING SPECIFIED PENOLOGICAL CHARACTERISTICS

Stream, Stand and Transect

1969 Date

No Growth Budding Leafing Flowering Fruiting

Lower Denton Creek

A 1 Apr 34 16 • • • • • •

C 1 Apr 33 17 • • • • • •

B 8 Apr 1 12 37 23a • #

Lower Elm

B 3 Apr 6 44 • • 6 • •

Fork B 8 Apr # • 6 44 41b

• •

B 22 Apr • • • • 50 • • 44

Upper Elm

A 1 May 8 35° 15 d • •

d 9 •

Fork B 1 Hay 1 46° 4

d • t

d • •

a Two on trees with leaf buds closed; 21 on trees with leaf buds open.

All on trees having leaf buds open.

c Buds showing on very few limbs only,

d Factor was not noted as being either absent or present.

57

Soil Particle Size Analysis

In an effort to locate a cause of variation between

stands and streams, soils were sampled at the A^ and

layers and particle size studied. Indirect measurements

were based upon the differential sedimentation rate of

TABLE XIV

BOUYOUCOS SOIL ANALYSIS - QUANTITY OF A 50-GRAM SAMPLE REMAINING IN SUSPENSION AFTER GIVEN PERIODS OF TIME

Stand and A^ Layer B-j Layer Transect

40 sec. 15 min. 2 hr. 40 sec. 15 min. 2 hr,

Lower A 40 g 29 g 21 8 43 8 35 g 27 j Denton Creek B 39 25 18 44 33 22

C 44 29 20 44 32 23

Upper A 44 35 25 43 33 23 Denton Creek B 43 33 23 38 27 19

C 44 36 27 38 27 21

Lower A 42 30 22 44 35 27 Elm -

Fork B 44 29 21 44 35 25

C 43 27 22 44 31 25

Upper A 44 / 28 19 44 30 23 Elm / /

17 Fork B 41 /v 26 17 39 23 17

C 40 24 16 39 21 15

0 58

various-sized particles from a water suspension. Fifty-

gram soil samples were dispersed according to the method

proposed by Bouyoucos (1930). Grams of the sample remaining

suspended were measured with a Bouyoucos hydrometer at 40

seconds, 15 minutes, and 2 hours after shaking the suspension.

Data obtained are presented in Table XIV.

Characteristics of the B^ layer determined by the 15-

minute readings were stated by Bouyoucos to indicate the

water-holding characteristics of the soil. Analysis of

variance of a comparison of these observations is presented

in Table XV.

TABLE XV

ANALYSIS OF VARIANCE - 15-MINUTE HYDROMETRIC READINGS B^ SOIL LAYER

Source of Variation DF SS MS F

Streams 1 12 12 0.16 n.s.

Stands 2 150 75 7.14 *

Soil Samples 8 84 10.5 •

No difference existed between streams in regards to soil

composition. The F value for between-stands comparisons,

however, did indicate difference significant at the five per

cent level. Little correlation was apparent between this set

of data and that for the hackberry population parameters.

59

Soil particle size was studied as an indication of mois-

ture-holding capacity of the soil. The original assumption

was that variations in soil moisture would affect the hack-

berry populations. Although this assumption is probably true

under other conditions, some pertinent factors were overlooked,

Since the stands occurred in bottomlands, the water table was

probably shallow. The water table was maintained at a

relatively high level because of the proximity of the stream.

These factors would negate the importance of soil particle

size in affecting the water supply available to flood plain

trees.

To complete the Bouyoucos soil study, unfree water and

moisture equivalent percentages were calculated. These values

are shown in Table XVI. According to Bouyoucos (1930), the

TABLE XVI

SOIL MOISTURE FACTORS - BOUYOUCOS DETERMINATION

Data Unfree Water

Moisture Equivalent

Minimum / / 11.9% 27.4%

Mean 17.1 39.2

Maximum 19.8 45.6

percentages of unfree water closely approximate wilting

coefficients. The above values fall in the general range

that is common for clay- and silt-loam soils.

60

CHAPTER BIBLIOGRAPHY

Bliss, C. I. 1967. Statistics in biology, vol. 1. McGraw-Hill Book Co., New York. 558 p.

Bouyoucos, G. J. 1930. The indirect determination of various soil characteristics by the hydrometer method. Soil Sci. 30: 267-272.

Laughlin, K. 1947. Big trees of the midwest. Amer. Midland Nat. 37: 788-793.

Phillips, E. A. 1959. Methods of vegetation study. Holt, Rinehart & Winston, Inc., New York. 107 p.

Swafford, M. L. 1969. Personal interview. 5 Aug. Ponder, Texas,

CHAPTER VI

CONCLUSIONS

Hypothesized difference between Celtis laevigata popu-

lations on two streams in Denton County was found not to

exist to a substantial extent. From F tests of the data

collected, the only significant difference at this level

occurred in the parameter of basal area density. Although

such a difference was found to exist to a significant degree,

variations and patterns of variation were noted.

Variations which were observed between the forests of

Denton Creek and Elm Fork were not definitely explained. Two

causative factors were considered. Soil particle size,

studied as an indication of moisture-holding capacity, was

determined not to be different between streams. No clear

correlation with variations among the hackberry populations

were evident. The anthropeic factors of lumbering and cattle-

grazing were considered, but no strong indication of either

was located. Residents of the localities near the flood plain

stands recollected little pertaining to the study areas

specifically. The only definite information indicated that

fuel wood was obtained from the upper Denton Creek stand prior

to the 1930*s on an irregular and partial basis. Although

evidence is lacking, man*s use of flood plain forests was

believed to be the major cause of existing variations,

61

62

The most significant concept derived from the study is

that the four stands studied may have represented different

phases of flood plain forest succession for the hackberry.

This idea is strongly suggested by the graphs showing size

distribution of the trees in each stand, and it is supported

to varying degrees by the other data. (The stages ranged from

a young, invading type of population in the lower Denton Creek

stand to a maturing population in the upper Elm Fork standj)

Most of the data obtained for various parameters of the

hackberry populations fit into the theory regarding succession.

!|he upper Elm Fork stand sampling had the largest total basal

area, characteristic of a mature tree population. The density

in this stand was low, primarily due to the lack of closely-

growing young trees///The low radial growth rate in the Elm

Fork stands may reflect overstory competition as well as

other factors which no longer favor hackberry tree growth.

Data regarding reproductives indicate the presence of less

favorable conditions for establishment of young hackberry

plants. No explanation was found for the delay in phonological

development of trees in the upper Elm Fork stand. Whatever

factors or conditions caused such a delay may be closely

related to those which resulted in the apparent pattern of

succession.!

In summary, this investigation revealed no major dif-

ferences between flood plain forest populations of the hack-

berry, Celtis laevigata. It did, however, suggest that

63

the stands which were sampled contained hackberry populations

in different stages of succession. As is true of many studies,

this one posed new questions and ideas for continued inves-

tigation.

Further study is needed to determine if the apparent

pattern of succession in the population holds true for the

community as a whole. Whereas these stands which were

studied occur on similar soils, a sandy substrate as on

Clear Creek may produce differences in plant growth. More

evidence should be obtained regarding how the flood plain

forests have been used and to what natural and anthropeic

influences the stands have been exposed. Investigations of

such questions may lead to a more thorough knowledge of

the dynamics of the ecology of the flood plain forest.

0

APPENDIX - SECTION A

DIAMETER BREAST HIGH, HEIGHT AND TRANSECT LOCATION

FOR INDIVIDUAL HACKBERRY TREES

64

65

TABLE I

INTERCEPT TRANSECT A - LOWER DENTON CREEK

Tree Number D B H a Height

Transect Distance*5

Lateral Distance0

1 2 3 4 5 6 7 8 9

10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40

7

25 ft, 30 30 15 25 30 15 30 18 18 15 25 20 18 35 18 18 20d

40 40 15 18 35 20 30 25 35 30 18 15 18 15 30 20 15 35 18 30 30 25

1 m. 4 14 30 37 41 46 51 51 53 56 56 59 59 63 71 74 78 79 82 85 99 129 147 168 170 171 171 186 198 204 206 216e

216 217 238® 247 247 263 265

1 1 0 1 0 0 0 4 0 1 1 2 1 2 2 2 2 0 1 3 1 1 0 1 1 1 1 0 0 1 0 1 1 1 1 1 1 0 1 3

m. right right

right

right

left right left right right left right left

left left left right

left right left left

left

left right left left left left

right right

66

TABLE I - Continued

Tree Transect Lateral Number D B H Height Distance Distance

41 5 in. 20 ft. 274 m. 1 m. right 42 1% 15 274 2 left 43 2 18 279 2 left 44 2% 20 282 1 right 45 2 18 288 1 left 46 2 15 295 0 47 1% 15 296 1 left 48 4 25 300 2 left 49 2 15 303 1 right 50 10 in. 35 ft. 312 m. 1 m. right

a Diameter breast high.

b Distance from transect base.

c Distance from transect line.

** Trunk was broken several feet above ground.

e Transect interrupted by clearing. Datum corrected accordingly.

67

, TABLE II I

INTERCEPT TRANSECT B - LOWER DENTON CREEK

Tree Transect Lateral Number D B H Height Distance Distance

I 2 in. 18 ft. 1 m. 0 m. 2 ih 12 2 0 3 4 25 10 2 left 4 9% 45 10 3 left 5 1% 15 27 2 right 6 3% 30 30 2 right 7 5 30 39 2 right 8 3 25 39 1 left 9 10% 35 67a 1 right

10 3 h 35 68 1 left 11 % 20 74 2 right 12 % 18 75 1 right 13 4 30 78 2 right 14 3 25 78 2 left 15 5% 35 78 3 left 16 4 25 81 2 right 17 25 86 2 right 18 2 k 18 91 1 left 19 1% 18 92 0 20 3 18 101 3 left 21 6 20 110 2 right 22 2 14 122 1 right 23 5% 30 124 3 right 24 10 40 144 1 right 25 4 30 164 1 left 26 7 35 168 2 left 27 8% 40 172 3 left 28 3% 20 185 1 left 29 8 35 207 1 left 30 4% 30 211 1 right 31 4 25 217 2 left 32 10 40 217 3 left 33 8 30 218 4 left 34 ; 1% 12 224 1 left 35 14 40 228 3 right 36 1% 20 238 0

right

37 1% 12 238 1 left 38 2% 25 239 0 39 2% 30 239 1 right 40 2 15 241 0

right

TABLE II - Continued

68

Tree Number

Transect Lateral D B H Height Distance Distance

1% in. 12 ft. 244 m. 1 m. left 3 25 245 1 right 2% 25 246 1 right 2 18 247 3 left 9% 40 247 4 right 6 40 249 3 right 12 40 249 4 right uk 40 249 3 left

35 251 1 left 2% in. 20 ft. 261 m. 1 m. right

41 42 43 44 45 46 47 48 49 50

a Transect interrupted by clearing. Datum corrected accordingly.

69

; TABLE III

INTERCEPT TRANSECT C - LOWER DENTON CREEK

Tree Transect Lateral Number D B H Height Distance Distance

1 10 in. 45 ft. 6 m. 1 m. right 2 12% 45 83a 1 right 3 5% 35 84 3 left 4 1% 18 90 0 5 2 20 92 1 right 6 6 35 92 2 right 7 ' 11% 40 98 3 right 8 1% 12 102 1 right 9 2 25 106 1 left

10 2 20 111 0 11 6 35 115 3 right 12 9 35 117 1 left 13 5 30 118 2 left 14 6 35 123 0 15 5 30 124 | 2 right 16 3% 20 126 j 0 17 4 30 129 0 18 10 40 129 2 right 19 3 25 130 0 20 3% 25 130 1 right 21 6 35 133 2,

2® right

22 1% 12 133 2, 2® right

23 3 25 134 2 right 24 4 30 134 2 left 25 6 35 136 1 right 26 3 30 138 1 left 27 5% 35 138 2 left 28 5 35 139 4 right 29 4 24 140 2 left 30 6 35 141 3 right 31 2 15 142 0 32 5% 40 142 2 right 33 3% 30 143 3 left 34 5% 35 143 3 c left 35 1% 15 144 1 right 36 7 40 146 3 left 37 2 12 146 2 left 38 10% 40 153 3 left 39 4 25 161 2 left 40 13 45 165 3 right

TABLE III - Continued </

70

Tree Transect Lateral Number D B H Height Distance Distance

41 15 in. 45 ft. 174 m. 4 m. right 42 6 35 210 0 43 6 35 214 1 right 44 3% 30 219 2 right 45 7 40 219 4 right 46 13*? 45 219 5 left 47 4 30 223 1 right 48 3% 30 236 2 right 49 4 30 245 1 left 50 13% in. 50 ft. 249 m. 2 m. left

a Transect interrupted by two clearings. Datum corrected accordingly.

71

; TABLE IV

INTERCEPT TRANSECT A - UPPER DENTON CREEK

Tree Transect Lateral Number D B H Height Distance Distance

1 3% in. 25 ft. 3 m. 0 m. 2 6 35 3 1 left 3 4% 35 4 2 right 4 4 35 5 0

right

5 4% 35 9 2 . right 6 5 35 13 1 right 7 7% 40 13 3 right 8 3% 25 17 1 right 9 6 40 21 2 right

10 1% 20 23 0 right

11 4 35 32 2 right 12 3 25 34 2 left 13 5 40 34 0 14 7% 40 38 1 left 15 6 30 43 1 left 16 10 40 43 2 left 17 2% 20 48 0 18 12 40 49 3 left 19 5% 35 51 0 20 3 25 57 0 21 1% 15 76 4 right 22 11 40 78 0

right

23 2 12 79 0 24 4% 35 90 0 25 4 . 35 95 1 right 26 2% 18 96 1 right 27 3 25 96 la right 28 2 25 97 3 right 29 3% 30 100 0

right

30 2% 30 101 0 31 4 30 103 2 rifcht 32 2% 20 104 1 left 33 35 109 1 left 34 2% 25 115 2 left 35 3 35 117 0 36 2% 30 118 1 left 37 3% 40 120 1 left 38 3% 35 120 1 right 39 3 35 120 0

right

40 2% 25 121 1 right

TABLE IV - Continued

72

Tree Transect Lateral Number D B H Height Distance Distance

41 2 in. 20 ft. 121 m. 1 m, right 42 4 35 122 1 right 43 3 25 131 2 right 44 3 20 131 0 45 5% 40 136 2 left 46 5% 40 136 0 47 9% 40 137 3 left 48 1% 18 140 0 49 4% 35 143 1 left 50 4 in. 25 ft. 171 m. 2 m . right

a Tree 27 was less than one-half meter from tree 26.

73

TABLE V

INTERCEPT TRANSECT B - UPPER' DENTON CREEK

Tree Transect Lateral Number D B H Height Distance Distance

1 9 in. 50 ft. 7 m. 2 m. left 2 2 12 12 2 left 3 2% 20 12 3 left 4 7% 40 12 3 right 5 7k 35 12 4 right 6 3 k 25 14 1 right 7 2 18 19 1 left 8 Ik 45 19 1 a left 9 2 10 19 1 right 10 7\ 40 20 1 right 11 5k 25 23 2 right 12 6% 35 27 4 right 13 6 35 34 2 right 14 10 40 35 2 right 15 7 40 37 0

right

16 2k 18 37 1 right 17 4 35 38 0

right

18 8% 50 45 1 left 19 3 30 55 2 right 20 10% 50 71 1 left 21 ik 25 77 0 22 9k 45 77 4 left 23 4 35 84 1 right 24 5% 35 90 2 left 25 2% 25 91 2 left 26 4 30 95 1 left 27 6 / 40 95 2 left 28 6 y 35 97 2 left 29 2% 7 25 99 2 right 30 2 25 103 0

right

31 4 40 104 0 32 5% 40 105 1 right 33 6 40 107 1 left 34 2 25 107 2 left 35 3 30 108 1 left 36 2 25 112 2 right 37 6% 40 123 < 5 left 38 14% 55 130 0 39 8 30 134 4 right 40 13 35 143 2 right

TABLE V - Continued

74

Tree Transect Lateral Number D B H Height Distance Distance

41 lk in. 18 ft. 153 m. 1 m. left 42 3 30 153 2 right 43 2 25 154 0 44 5k 35 157 0 45 12 45 159 3 left 46 7 35 163 2 right 47 1% 25 165 1 right 48 3 35 166 1 right 49 3 40 167 2 left 50 3 in. 25 ft.

U

168 m. 1 m. left

a Tree 8 was less than one-half meter from tree 7,

75

TABLE VI

INTERCEPT TRANSECT C - UPPER DENTON CREEK

Tree Transect Lateral Number D B H Height Distance Distance

1 2 in. 25 ft. 3 m. 2 m. right 2 5% 35 6 2 right 3 6 35 6 2 right 4 5 35 9 1 left 5 6% 35 20 4 right 6 4% 35 22 1 right 7 9% 35 23 3 left 8 7 35 23 4 right 9 3% 25 30 4 right 10 10% 50 31 6 right 11 7% 35 36 4 left 12 5 40 41 0 13 6 35 42 1 left 14 9 45 44 4 right 15 3 25 44 2 left 16 6 30 54 3 right 17 5% 35 60 0

right

18 6% 35 60 1 right 19 5 30 60 la right 20 12 45 65 4 left 21 8% 40 65 8 right 22 11 45 67 4 left 23 12 40 73 4 right 24 7 35 73 4 right 25 7 35 75 4 left 26 15 45 75 5 left 27 13 40 76 5 left 28 1% 15 81 1 left 29 4 35 90 1 left 30 6% 40 90 0 31 40 91 2 right 32 6% 35 95 1 right 33 6% 35 95 2 right 34 2% 25 99 1 left 35 3 30 100 1 right 36 4% 30 103 2 left 37 5 35 105 0 38 2% 30 110 0 39 3% 30 111 0 40 4 25 113 2 right

TABLE VI - Continued

76

Tree Transect Lateral Number D B H Height Distance Distance

41 7% in. 35 ft. 115 m. 1 m. left 42 9% 35 122 3 left 43 9 45 124 1 left 44 3 20 124 2 left 45 6 35 127 2 left 46 5 30 127 1 left 47 3% 20 129 1 left 48 7 35 129 4 right 49 8 40 131 2 left 50 4 in. 30 ft. 131 m. 1 m. left

& Tree 19 was less than one-half meter from tree 18,

77

TABLE VII

INTERCEPT TRANSECT A - LOWER ELM FORK

Tree Transect Lateral Number. D B H Height Distance Distance

I 10% in. 40 ft. 2 m. 0 m. 2 2% 20 11 1 right 3 8 35 18 3 right 4 6% 35 20 1 left 5 16% 50 20 5 right 6 6 35 24 1 left 7 10% 45 29 1 right 8 15 45 36 5 left 9 4 18 61 4 left

10 9% 35 61 7 left II 12 35 70 3 left 12 9% 40 75 1 left 13 7% 30 87 4 left 14 10% 40 91 8 left 15 14% 45 95 8 left 16 8% 35 98 2 left 17 16% 50 101 3 right 18 6% 35 106 1 right 19 6 35 109 0

right

20 12 40 117 3 left 21 2% 18 118 1 left 22 3 20 127 0 23 3% 25 129 2 left 24 3 25 130 1 right 25 4 25 134 1 left 26 12 135a 0 27 8% 35 138 2 left 28 7% 30 145 3 right 29 1 2h 184 1 right 30 9% 30b 200 2 right 31 3 20 206 2 right 32 1% 12 214 3 right 33 2 18 215 3 right 34 3% 25 217 0

right

35 11 40 220 1 right 36 12 35 223 3 right 37 2 15 228 1 right 38 3 25 234 0

right

39 3 25 234 1 left 40 3 20 247 1 right

78

TABLE VII - Continued.

Tree Transect Lateral Number D B H Height Distance Distance

41 3 in. 25 ft. 249 m. 3 m. right 42 5 30 251 2 right 43 2 18 254 1 left 44 4 25 255 0 45 6 35 256 2 right 46 4 25 257 0 47 4% 25 257 2 right 48 2k 18 258 2 right 49 2 18 260 1 left 50 5 in. 30 ft. 263 m. 2 m. left

a Transect interrupted by a pond. Datum corrected accordingly.

b Tree leaning with trunk at about a 45° angle.

79

TABLE VIII

INTERCEPT TRANSECT B - LOWER ELM FORK

Tree Transect Lateral Number D B H Height Distance Distance

I 7 in. 30 ft. 17 m. 1 m. right 2 14 45 21 0

m. right

3 7% 20 24 1 right 4 10% 35 31 2 left 5 6 25 38 0 6 8 25 38 1 right 7 7 35 43 1 left 8 13% 50 48 1 right 9 12 50 56 0

right

10 12 30 61 1 left II 4 15 64 1 right 12 15% 40 65 5 left 13 8 30 71 5 left 14 10% 45 71 0 15 10% 45 72 , 2 right 16 5 30 75 0

right

17 9 45 77 3 left 18 5% 25 79 1 right 19 6% 35 79 3 left 20 5% 30 83 3 left 21 4% 30 84 1 left 22 4 20 91 3 right 23 11 35 95 1 left 24 9% 35 100 0 25 4 30 101 2 left 26 8 35 101 1 right 27 7 35 103 0

right

28 5% 35 103 2 right 29 7% 35 105 1 left 30 6 35 105 1 right 31 2 10 106 1 right 32 4 30 107 1 right 33 4% 30 108 2 left 34 9 35 114 2 right 35 4 30 116 2 right 36 4% 50 118 3 left 37 8 40 126 2 right 38 4% 25 127 1 left 39 8 35 134 0 40 4 20 139 0

TABLE VIII - Continued

80

Tree Transect Lateral Number D B H Height Distance Distance

41 8 in. 35 ft. 154 m. 0 m. 42 10 35 156 5 left 43 7% 35 157 1 right 44 9% 40 159 2 right 45 9 35 167 1 left 46 8 30 175 2 right 47 6 30 177 4 right 48 Ik 12 178 1 right 49 5k 30 232 0

right

50 6 in. 30 ft. 234 m. 0 m.

81

TABLE IX

INTERCEPT TRANSECT C - LOWER ELM FORK

Tree Transect Lateral Number D B H Height Distance Distance

I 6% in. 25 ft. 13 m. 5 m. right 2 31 45 17 6 right 3 8 35 19 4 left 4 13 45 25 6 left 5 10% 40 28 0 6 11 35 30 1 right 7 11 30a 31 1 right 8 7% 35 37 3 left 9 5? 30 38 3 left 10 10% 40 44 4 right 11 8 25 49 2 left 12 20% 50 51 2 left 13 10 40 57 1 left 14 8 40 58 4 right 15 8% 40 65 3 right 16 10 35 73 1 left 17 7% 35 73 4 right 18 9 40 76 5 right 19 11% 30 81 1 right 20 6% 25 87 2 right 21 3 15 89 1 right 22 2% 15 92 4 right 23 4 30 94 2 left 24 9% 40 99 0 25 9 35 100 2 right 26 7% 35 103 1 right 27 4% 25 108 3 left 28 4 25 110 1, left 29 8 35 113 1 left 30 6% 30 114 2 right 31 10 40 120 0

right

32 8% 40 124 1 right 33 8% 35 131 . 1 left 34 6% 30 131 4 right 35 6 30 132 3 right 36 6% 30 136 1 left 37 2 15 160 1 right 38 3 15 162 1 right 39 5% 18 167 1 right 40 3 18 167 2 left

TABLE IX - Continued

82

Tree Transect Lateral Number D B H Height Distance Distance

41 4 in. 15a ft. 169 m. 1 m. left 42 1% 15 171 1 left 43 5 25 174 0 44 2% 12 175 1 right 45 7k 35 177 5 right 46 1\ 40 179 5 right 47 1§ 12 179 1 left 48 5% 30 186 1 right 49 5 35 195 1 right 50 10% in. 40 ft. 195 m. 0 m.

A Trunk broken several feet above ground.

83

TABLE X

INTERCEPT TRANSECT A - UPPER ELM FORK

Tree Transect Number D B H Height Distance

1 7% in. 35 ft. 11 m. 2 7 / 30 17 3 13 0 50

' 25 36

4 7 / 0 50 ' 25 37

5 8% 40 39 6 7% 35 47 7 12 40 51 8 8% 35 61 9 8 35 73

10 17 60 75 11 8% 40 79 12 12 55 89, 13 8% 45 94 14 6% 25 104 15 8 35 110 16 5% 30 114 17 11% 55 120 18 14 70 120 19 10 40 124 20 10 35 134 21 4 25 142 22 10% 50 146 23 4 18 153 24 7% 30 180 25 7% 30 210 26 10 35 238 27 10% 45 247 28 17% 50 250 29 13 35 255 30 16% 55 261 31 2% 20 266 32 12 40 270 33 23% 50 271 34 5% 30 272 35 18% 40 278 36 9% 35 281 37 7 30 284 38 18 55 292 39 2 12 292 40 8% 40 295

Lateral Distance

3 m, left 3 right 8 left 4 left 3 right 5 right 3 left 5 right 1 right 1 right 4 right 2 left 3 right 3 right 4 right 3 left 2 left 6 left 4 right 0 0 4 left 1 right 2 left 0 0 6 left 9 left 1 left 1 left 3 right 6 left 4 right 1 left 7 left 2 right 2 left 0 3 right 3 left

TABLE X - Continued

84

Tree Transect Lateral Number D B H Height Distance Distance

41 13% in. 45 ft. 299 m. 7 m, left 42 ll£ 40 300 5 right 43 4 40 302 3 right 44 9% 35 304 4 left 45 Ik 35 304 5 right 46 17% 45 311 1 right 47 16 35 326 7 left 48 6 25 332 1 left 49 15 45 337 2 left 50 3% in. 20 ft. 349 m. 1 m, left

85

TABLE XI

INTERCEPT TRANSECT B - UPPER ELM FORK

Tree Transect Number D B H Height Distance

1 13% in. 50 ft. 12 m. 2 10 40 16 . 3 4 30 19 4 10 45 21 5 13% 50 24 6 7 40 24 7 6% 25 30 8 12% 50 35 9 9 40 37

10 8% 40 46 11 7 40 47 12 3% i 15 50 13 8 30 53 14 8 35 55 15 6% 20 65 16 13 45 81 17 6 25 108 18 9 % 35 142 19 11 35 174 20 13 40 184 21 10% 45 191 22 4 30 193 23 4% 30 193 24 11 45 195 25 5 30 196 26 13% 55 200 27 9 40 200 28 3% 20 203 29 8 30 203 30 8 35 209 31 6 40 213 32 10% 40 214 33 13% 55 216 34 9% 40 226 35 8 30 236 36 8 35 238 37 18 50 255 38 10 35 257 39 16% 35 266 40 9 35 279

Lateral Distance

1 m. 1 4 5 1 3 2 0 2 1 4 2 2 2 4 3 4 4 4 7 3 0 2 2 3 1 2 4 2 5 1 0 2 5 2 2 5 4 I 5

right left left right right left right

left right right left left left left right left right left right left

right left right right left right right right right

left right right left left right right left

TABLE XI - Continued

86

Tree Transect Lateral Number D B H Height Distance Distance

41 17% in. 55 ft. 281 m. 7 m. right 42 10 50 285 0 43 12 55 288 4 right 44 19 70 290 10 right 45 9 40 291 3 right 46 14 60 294 7 right 47 6 35 300 2 right 48 1% 15 329 2 right 49 3 25 339 0 50 2% in. 20 ft. 340 m. 1 m. left

37

TABLE XII

INTERCEPT TRANSECT C - UPPER ELM FORK

Tree Transect Lateral Number D B H Height Distance Distance

I 7% in. 35 ft. 47 m. 3 m. right 2 6 35 48 0 3 11 40 49 2 right 4 6 30 53 3 right 5 8% 30 64 5 left 6 8 35 65 3 right 7 4% 35 66 4 left 8 9 40 67 3 left 9 5% 35 72 4 left 10 5% 30 75 2 right II 6% 35 75 0

right

12 11 45 76 1 left 13 14 55 80 2 right 14 12% 45 80 2 left 15 6 40 84 3 right 16 5% 35 85 2 right 17 6 25 112 3 right 18 8 40 112 4 right 19 5 40 112 1 left 20 4% 25 113 1 right 21 5% 35 115 0

right

22 7% 25 118 3 left 23 4% 20 121 0 24 10 35 132 1 right 25 9% 40 135 5 right 26 5 30 135 1 left 27 8% 45 143 4 right 28 10 40 180 4 right 29 6% 30 186 3 right 30 10 50 195 3 left 31 8 35 197 3 right 32 i % 15 205 1 right 33 19 65 205 2 right 34 5 30 205 2 left 35 11 45 214 1 left 36 5 30 231 1 right 37 16% 50 233 3 right 38 9% 40 237 0

right

39 6% 35 237 3 left 40 7 35 248 4 right

TABLE XII - Continued 7/

88

Tree Transect Lateral Number D B H Height Distance Distance

41 II in. 40 ft. 255 m. 2 m. right 42 9% 40 255 4 left 43 16 50 265 4 right 44 8% 45 270 4 right 45 8 40 273 1 left 46 13% 50 275 2 left 47 16% 70 276 3 right 48 9% 35 277 3 right 49 9% 40 286 1 left 50 18 in. 70 ft. 287 m. 1 m. left

89

APPENDIX - SECTION B

DIAMETER BREAST HIGH OF INDIVIDUAL TREES OF OTHER SPECIES

INTERCEPTING THE 50-HACKBERRY-TREE TRANSECTS

90

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