University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange
Masters Theses Graduate School
3-1968
The Ecology of Pieris floribunda Benth. and Hook., an Ericad, in a Pine-Heath Community in the Great Smoky Mountains
Caroline Triplett Wingfield University of Tennessee - Knoxville
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Recommended Citation Wingfield, Caroline Triplett, "The Ecology of Pieris floribunda Benth. and Hook., an Ericad, in a Pine-Heath Community in the Great Smoky Mountains. " Master's Thesis, University of Tennessee, 1968. https://trace.tennessee.edu/utk_gradthes/3208
This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council:
I am submitting herewith a thesis written by Caroline Triplett Wingfield entitled "The cologyE of Pieris floribunda Benth. and Hook., an Ericad, in a Pine-Heath Community in the Great Smoky Mountains." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Botany.
Edward E.C. Clebsch, Major Professor
We have read this thesis and recommend its acceptance:
H.R. DeSelm, James D. Caponetti
Accepted for the Council: Carolyn R. Hodges
Vice Provost and Dean of the Graduate School
(Original signatures are on file with official studentecor r ds.) Decembe r 15, 1967
To the Graduate Council :
I am submitting he re with a thesis writte n by Caro l ine Triple tt Wingf ie ld entitled .,The Eco logy of Pieris floribunda Benth. and Hook. , an Ericad, . in a Pine -He ath Community in the Gre at Smoky Mountains. " I recomme nd that it be acce pted for eighteen quar te r ho urs of credit in pa rtial fulfillme nt of the requirements for the de gre e of Maste r of Science , with a ma jor in Botany .
fkYML f(!_ �dJ Ma jor Profe ssor
We have re ad this thesis and recommend its acce ptance :
Acce pted for the Counci l:
� £�--zt V1ce Pres1dent for Graduate Studies and Re search THE . EC OIDGY OF PIERIS FLORIBUNDA BENTH. AND HOOK. , AN ERIC AD,
IN A PINE-HEATH COMMUNITY IN THE GREAT SMOKY MOUNTAINS
A Thesis
Pre se nte d to
the Gra dua te Council of
The Unive rsity of Te nnessee
In Partial Fulfillme nt
of the Re quireme nts for the De gre e
Ma ste r of Sc ie nce
by
Caroline Triple tt Wingfie ld
Ma rch 1968 AC KNOWLEDGEMENTS
The author wis hes to expre ss si nce re appreciation to the othe r
gra duate stude nts in the Bota ny De partme nt for the ir advice and criti cism of the the sis and for the ir ass is ta nce in completing the fie ld
work.
Special tha nks are exte nded to my fa the r, Dr. Harve y N. Wingfie ld,
Jr. and Mr. M. D. Ke rby, Jr. for the chemical analys is of the soil sample s.
For identification of the lichens in the study area, the author wishes to thank Mr. !s ao Yos himura .
The author is grateful to he r ma j or professor, Dr. Edwa rd E. C.
Clebsch, and also to Dr. H. R. DeSe lm and Dr. Jame s D. Capone tti for the ir cri ticism of the thesis.
The he lp extende d to the author by the sta ff of the Great Smoky
Mounta ins Nationa l Pa rk is greatly appreciated. Tra ve l ne ce ssary for this study wa s partia lly supporte d through contra ct No. 14-10-0117-634 be tween the Na tiona l Pa rk Se rvice and The Unive rs ity of Te nnessee .
This assistance is gratefully acknowle dge d.
ii
769367 TAB IE OF CON'IENTS
SECTION PAGE
I. INTRODUCTION. 1
Objectives. 1
The Study Area. 1
Vege tationa l Studies. 9
II . METHODS • • 15
III . RES ULTS 19
Frequency of Trees .. 19
Density and Basal Are a of Trees . . 21
Fre quency and Density of Shrubs . . 25
Herbace ous Cove r .. 25
Pie ri s floribunda 27
Envi ronme ntal Study . 29
IV. DISCUSSION AND CONCLUSIONS. 43
V. SUMMARY •. 48
LITERATURE CITED . 50
54 APPENDIXES. . • .
A. PROCEDURE FOR THE PREPARATION OF SOIL SAMPlES . 55
57 B . SUMMARY OF TREE TAXA IN DIAMETER ClASSES BY PI.DT. • .
65 c. SUMMARY OF SHRUB TAXA IN DIAMETER ClASSES BY PI.DT •
iii US T OF TAB lES
TABlE PAGE
I . Pe r Cent Freque ncy of Tree Species in the Tree Stra tum,
Unde r One Inch Diamete r and As Seedlings ..... 20
II . Me an De nsity Pe r Plot and Pe r Cent To ta l Basal Are a of
Trees in the Study Are a 22
III . Species Pre sent and The ir Frequency in the He rbaceous Cove r . 26
IV. The Me an, Stand ard De viation and Range of Several
Cha racte rs of Pie ris floribunda . .... 28
V. Va lue s of Compone nt s of Re gre ss ion Equations of Tempe rature s. 37
VI . Soil Prof iles and pH Va lue s from the Bullhe ad Tra il Pine -
He ath and a Pine -He ath at 2800 Feet Elevation Studied
by McGinnis 40
VI I . Ava ilab le Cations of Soils in the Study Area. 41
iv US T OF FIGURES
FIGURE PAGE
1. Re product ive Structure s .of Pieris floribund a, Benth . and
Hook . (a) Flowe r, X5; (b) Capsule, X4; (c) Seed, lOX
(from Wood, C. E. , 1961) . . . . . 4
2. World Distribut ion of the Genus Pie ris (from Li, Hi-Lin,
1952) ...... 5
3. Pieris floribunda Growing Along Blue Ridge Pa rkway Ne ar Mt .
Pisgah, North Carolina (S pring, 1967) . . . 7
4. Bu l lhe ad Trail in Study Are a (Fall, 1966) . 10
5. Ae ria l Photograph of Bullhe ad Trail in the Vicinity of the
Study Are a 16
6. A Comparison of Diame te r Distribut ion of All Stems in Two
Pine -He ath Stands : the Study Area and a Stand Inve st i-
gated by Whit taker (1956) ..... 23
7. (a) Pinus pungens in Pine -He ath Community Studied by Whittaker
.(1956) . (b) � · punge ns in Study Are a ...• ...... 24
8. Ave rage Max imum Tempe rature s for Five Stations in Study Are a
for the One Foot Leve 1, Litte r, and Soil . . 30
9. Ave rage Minimum Tempe rature s for Five Stations in Study Are a
for the One Foot Leve1, Litte r, and Soil 31
10 . Comparison of Ave rage Max imum Tempera ture s for Th ree Areas
in Gre at Smoky Mounta ins Nat iona l Park : Park He adquarte rs,
Study Are a, and Ne wf ound Gap . 33
v vi
FIGURE PAGE
11 . Comparison of Ave rage Minimum Te mperature s for Three Are as
in Great Smoky Mount ains Nat iona l Pa rk: Pa rk He ad-
quarte rs, Study Area , and Ne wf ound Gap .
12 . Re lation of Ne wfound Gap and Study Are a Maximum (a) and
Minimum (b) Te mperature s . 35
13 . Re la tion of Park He adquarters and Study Are a Max imum (a)
and Minimum (b) Te mpera ture s 3 6
14 . A Comparison of the Cumu lative Rainfall for Three Location s
in Gre at Smoky Mounta ins Nationa l Pa rk: Ne wfound Gap ,
Study Area, and Pa rk He adqua rte rs .... 39 I . INTRODUCTION
Objective s
A membe r of the he ath family , Ericaceae , Pieris floribunda
Benth . and Hook. is endemic to the Southe rn Appa lachian Mountains, its
distribution be ing concentrated in the highe r elevations of the Great
Smoky Mount ains Na t iona l Park.
For ma ny ye ars these sma ll shrubs have be en noted grow ing bes ide
the trails in the Pa rk in some of the most xe ric hab itats , especia lly
pine -he ath communities , along with othe r ericaceous plants . By close
examination of the clima tology, soils and associated ve ge tation of
the se habit ats, it was hoped tha t some clues might be found as to
what factors allow �- floribunda to survive a�d re produce in the se
xe ric habitats . Through inve stigat ion of the above and. ce rtain aspects
of the aute cology of Pieris, the ve geta tiona l role of this he ath shrub
in this particular community might be clarified .
The Study Area
The Gre at Smoky Mount ains of we stern North Carolina and eastern
Te nne ssee are an area of gre at environmenta l and ve ge tationa l divers ity .
Mt . LeC on te , with a pe ak elevation of 6593 feet, is one of the highe st
mounta ins in the. re gion . Located on it s wes tern slope is the Bu llhead,
the site of this study.
Whittaker (1956) de scribe s fifteen ve ge tation types as be ing
pre sent in the Great Smoky Mount ains Nat iona l Park. The ma jority of
1 2 the se would be encounte red on asce nding Mt. LeConte . The pine -heaths , with which thi s paper is conce rned , are characte rized by pine woods wi th a dense unde rstory of he ath shrubs. The y are most freque nt on sout he rn exposure s between 3000 and 40 00 feet in elevation . The se pine-he aths occur predominantly on ridge s and may extend from the cove hardwood zone to the ve ry lowe r limit s of the spruce -fir zone. Such a wide distribution is to be seen on the Bul lhe ad Trai l. The topo graphic distribution of the se pine-he aths is comparable to that of the heath balds , but at a lowe r elevation than the se (Cain , 19 3la).
The parent rocks of most of the soils of the Great Smoky
Mountains are quartzites , slate s and sandstone s (Had ley and Goldsmith ,
1963). Gene ra lly, the soils are acid with the gre ate st acidi ty occurring in the highe st elevations and most exposed site s (Whittaker,
1956). Cain (193lb) found that a pine-he ath at 3400 feet elevation in the Gre at Smoky Mountains had an ave rage soil depth of six inche s and an average pH of 4.9 for the surface soils wi th a range from 5.6 to 4. 1, and an ave rage pH of 5.0 for the subsoil with a range of 5.8 to 4.5.
The climate of a pine-he ath at an elevati on of 4000 feet falls within the pe rhumid class of the Thornthwaite (1948) climatic classi fication. Pre cipit ation at this elevation is between 78 inche s and
89 inche s per ye ar , based on a five ye ar me an (Shanks , 1954). Accord ing to Tanne r (196 3) , the is othe rms of dai ly maxima on north-f acing slope s follow the altitudinal contour line s. Howeve r, on south-f acing slope s , the isothe rms are pe rpendicular to the contours. For examp le , 3 a ridge exte nding down a mountainside which would probably be occupied by a pine -he ath or he ath bald, wou ld have an isothe rm conne cting its uppe r and lowe r limits .
Pieris
The nomenc lature of the species of Pie ri s follows that found in
Bai ley (1930). Fa lser (1952 ) dis cus sed the various characte rs employe d to de limit the larger plant group s in the Erica le s, espe cially the mega sporogenesis and the deve lopme nt of the me gagame tophyte in the
Andromedeae .
The entire ge nus may be cha racte rize d by the followi ng: the fl le aves alte rnate, short pe ti oled, entire or serrulate: flowe rs in of ten panicled raceme s; calyx- lobe s va lvate or di s tinct; stamens ten; anthe rs ob tuse, wi th a pair of awns ne ar the base or the fi laments two-toothed be low the apex: capsules wi th five dehiscent va lve s; seeds line ar-oblong, not wi nged, wi th membranous te sta" (Bai ley, 1930).
Figure 1 illustrates the typical flowe r, fruit and seed of Pie ri s floribunda.
The genus Pie ri s is quite dive rsified in many re spects, being both deciduous and eve rgreen, varying from small shrubs to trees 40 feet in height and with a geographical range wi th one ce nte r in eastern
Asia and the othe r in the easte rn ha lf of the United States. In the
United States, Pie ri s' range exte nds from We st Virginia, we stern
Vi rginia, we stern North Carolina, to eastern Te nne ssee, and northe rn
Ge orgia . The world dis tribution of Pi eris is shown in Figure 2. 4
{a)
{b) (c)
Figure 1. Re product ive structure s of Pie ris floribunda, Benth . and , Hook . (a) Flowe r, XS; .(b) capsule, X4; (c) seed, XlO (from Wood C. E., 196 1). 5 6
Pieris floribunda is considered as ende mic to the Una ka range
of easte rn Te nne ssee and we ste rn North Carolina, with its distribution
ce ntering in the Gre at Smoky Mountains (C ain, 1930). Whittaker (1956)
found tha t the dis tribution of P. floribunda in the Smokie s ce ntered
in xe ric sites and at time s extended into subxe ric and subme sic one s.
Us ually �· flor ibunda is limited to elevations above 4000 fe et in the
Smokie s, but sc attered plants ha ve bee n se en along the Bu llhead Trail
extending as low as 3000 fe et in elevation. Along the Blue Ridge Pa rk
way in North Carol ina, P. floribunda occurs at lower eleva tions as is
se en in Figure 3.
Pieris is cu ltivated as an orna menta l shrub in many locations;
P. floribunda and P. mariana are used in the northe rn Unite d Sta te s whe re the y are va lue d for the earline ss of the ir flowers. �· japonica, which wa s introduce d from Ja pan, and � - formos a, from the Ea stern
Himalayas, are cons idered the mos t be autiful. P. fo rmosa is re stricte d to the southe rn re gions of the Unite d Sta te s whi le �- japonic a may appear as far north as Ma ssachuse tts, but in tha t environme nt, the flowe rs are usua lly winte r killed (Ba iley, 1930).
The migration and evolution of the Androme de ae in No rth Ame rica has be en considered by Lem s (1962). He ight growth in the Androme de ae is achie ved by a succe ssion of lateral buds since the te rm ina l shoot me ristem ha s a limited life span. The se que nce of a "mo rphoge ne tic cyc le " inc lude s the fo llowing: (1) early bud gr owth, wi th de ve lopme nt of sca le le aves; (2 ) growth of leafy shoots; (3) inflore sce nce fo rma ti on and forma tion of the flower buds ; (4 ) me iosis, pollen and ovu le Figure 3. Pieris floribunda growing along Blue Ridge Parkway near Mt . Pisgah , ...... North Carolina ( spring, 1967). . 8 maturation; (5) flower opening, subsequent pollinat ion, and fertiliza tion; (6) fruit maturation; and (7) dehis cence of fruit and seed dis persal . The time of interruption of th is sequence by dormancy is the criterion Lems uti lizes to distinguish three main types of deve lopment in North America among the Andromedeae.
The cyc le of Pieris is as follows. In May and June new lateral shoots are produced and by August the leaves are mature and the in florescences have formed (Lems, 1962). The anthers over winter in the microspore mother-cell stage. These reach the tetrad stage before the ovu les have develope d further than the megaspore mother-cell stage
(Palser, 195 1). Flowering occurs in the following spring even though meios is occurred in the previous Ju ly and August. Maturation of the fruit usually is by Ju ly. Over wintering in th is condition may also indicate the tropical origin of these spec ies where flower dormancy became a means of su rvival upon migration.
The one- season cyc le, in wh ich the whole reproductive cyc le is completed in one year, is said to be the bes t adaptation to the alter nation of summer and winter seas ons. Oxydendrum exhib its such a cycle.
Other members ·of the Andromedeae from South and Central America (�·�·,
Lyonia) need two complete growing seas ons for one "morphological cyc le," and Lems (1962) specu lates that as these tropical Andromedeae migrated northward, surviving the winter seas on was accomplished thus ly: acceleration of the cycle, dormancy of flowers, and de lay of inf lorescence formation . For Pier is floribunda, survival seems to have been accomplished by dormancy of the flowers (Lems, 1962). 9
Ve ge tationa 1 Studies
It ha s been note d by Whittaker (1956) that most ma ture pine stands in the Great Smoky Mountains are of mixed specie s whi le im- mature one s are usually single -spe cie s stands . The pi cture in Figure
4 was taken from the trai l in the Bullhe ad pine-heath whe re the stand . 1 1s pre d om1nant. 1 y �p· pungens.
According to Cain (1937) fire is the leading factor in the main- tenance of pine -heaths . As de ciduous trees ma ke their appe arance he re, it can be seen that as they increased in numbe r, the pines wou ld de - crease and fina lly be eliminated. The refore , the pine-heath is mos t li ke ly a transitory stage . However, si nce its duration may be more than a century and may be pe rpe tuated at times by fire s, Cain con- side rs it an edaphic or topographi c climax .
Whittaker (1956) di s tinguishes two pine-he ath communities in the Smokie s on the basis of thei r dominants: pitch pine (Pinus rigida) and table mountain pine (�. pungens). The pitch pine he ath is usua lly found be tween the elevations of 2200 to 32 00 feet. Que rcus coccine a is usua lly pre sent and at times may share domi nance wi th the pine.
2· prinus and Castanea dentata are almos t always present along wi th
Acer rubrum and Oxydendrum arboreum. Shrub cove rage range s from 40 to 70 per cent and the he rbaceous cove r usua lly range s from 5 to 20 pe r cent . Kalmia latif olia and Vaccinium vacillans or V. hi rsutum usually dominate the shrub stratum wi th Andropogon scop arius, Pteridium
1 Nomenclature follows that of Fernald (1950). 10
Figure 4. Bullhead Tra il in study area (fall, 1966) . 11 aqui linum var . latiscu lum , Epigaea repens , Gaulthe ria procumbens dom inating the he rbace ous layer. The table mountain pine-heath occurs toward the upper limits of the pine-heaths . At the se highe r elevations , the y are characte rized by low sta ture and density. The mos t preva lent spe cie s in the tree stratum after Pi nus pungens are �- rigida , Que rcus coccinea , Q· prinus , Castanea dentata , Nyssa sylvatic a, Ace r rubrum ,
Oxydendrum arboreum , Robinia pseudo-acacia , and Sassafras albidum .
Ka lmia latifolia and the Vaccinioideae are the dominants of the shrub stratum wi th a total shrub cove r of 60 to 90 pe r ce nt. Whittaker states that Pieris floribunda may be a dominant at the highe r elevations .
Galax aphylla , Epigaea repens and Gaulthe ri a procumbens are the major specie s in the he rbaceous laye r wi th a cove rage of only 5 to 20 per cent .
Whittaker (1966) found tha t the above-ground ne t annua l produc
2 ti on is 420-650 g ./m . for fore st he aths of xeric slope s and forests of hi ghe st elevations as compared to 1000-1200 g ./m .2 for mature clim ax forests of me sic envi ronm ents . He also found that shrub production is usua lly highe r in xeric envi ronments , being 20- 145 pe r ce nt of tree production in forest he a ths.
In the southeastern portion of the Blue Ridge Escarpme nt , a study was conducted by Racine (1966) of pine ridge communitie s. He found a two to three inch immature mor humus layer composed of a li t te r and fe rmentation zone but lacking the humus zone. The soil itse lf is characterized by low nutrient content , the calcium concentration neve r exceeding 50 p.p.m . and potassium neve r above 80 p.p.m. 12
Racine (1966) des cribes two community types for these ridges, the pine community and the pine-oak community. The pine community was found to occupy the dr ies t ridges with scattered individua ls of
Quercus coccinea, Nyssa sy lvat ica, Quer cus pr inus and Acer rub rum.
A heath of Ka lmia latifolia or Vac cinium vac illans may occur in patches. The pine-oak commun ity is characteristic of les s xer ic ridges. There is a higher pr oportion of oaks in comparison to pines and the heath is much more prevalent. This community seems to be more close ly related to the pine -heaths of the Great Smoky Mountains than the pine commun ity. Coope r (1963) and Rodgers � 1965) found this same relationship to be true of other pine communities in North Carolina wh ich they investigated.
Wi lliams and Oosting (1944) in a study of the vegetation of
Pi lot Mountain, North Carolina, found Pieris floribunda to be the dominant shrub spec ies occurring with Ka lmia latif olia, Rhododendrum catawb iense, Smi lax rotundifolia, and Vac cin ium corymbosum var. pa llidum . Pilot Mountain is in the northwestern Piedmont of North
Carolina and is iso lated from the Blue Ridge. The peak elevat ion is approximately 2000 feet. Pinus pungens, �· rigida, Oxydendrum arboreum, Ny ssa sylvatica, Acer rub rum, Quercus borealis var. maxima and Robinia pseudo-acacia constitute the tree stratum. All factors ex cept altitude corres pond to what Cain (193la) refers to as sub climax pine-heaths in the Great Smoky Mountains.
In a study of the vas cu lar flora of the Southern Appalachians,
Ramseur (1960) found Pieris to be present in three different 13 commun itie s: in a he ath ba ld in the Plott Ba lsam Mountains , a shrub ba ld on the Pisgah Ridge and in the fire cherry , grassy bald , he ath bald , and shrub bald commun it ies in the Balsam Mounta ins. He dis tingu ishe s the shrub bald from the he ath bald in that specie s of shrubby trees usua lly found at lower altitude s are preva le nt in the shrub ba ld .
Davis (1930) classifies the ve ge tation of the Black Mountains of North Carolina into three formations , the spruce -f ir forest , the northe rn ha rdwood fore st and the Appa lachian forest. He further sub divide s the Appa lachian forest forma tion into three minor commun it ie s, the cove climax , the me sic slope , and the xe ric slope and ridge as soci at ions .
The cove climax associat ion is composed of southe rn hardwood specie s and cha racte ristica lly ha s an unde rstory of he ath shrubs. It is difficu lt at time s to dist inguish be tween the cove climax assoc ia tion and the me sic slope association . The me sic slope association wa s also found to inte rgrade into the xe ric slope and ridge associa tion at its uppe r limits . Howeve r, this association is se t off from the othe r two be cause of the scarcity of he mlocks and pine s and the abundance of oaks . An unde rstory of he ath shrubs is pre sent he re also.
The xe ric slope and ridge association is limite d to the dry slope s and ridge s and is characterized by the dominance of pine s and a fe w oaks .
The pine s may ofte n form pure stands . The unde rstory of he ath is pre se nt and may be extremely abundant at times . 14
Davis found Pie ris floribunda with a mode rate percentage of frequency or abundance in the mesic slope associa tion and to be both this and locally abundant as a consociation or clan in the xeric slope and ridge association . I I . :METHODS
Spe cime ns of Pieris from he rbaria in the Great Smoky Mountains re gion we re examine d and the collection sites noted. From this , a list was compiled of locations of Pieris floribunda within the Great
Smoky Mountains Na t iona l Park and the se locations we re visited. The pine -heath community traversed by the Bullhead Trail , Mt . LeConte , was chosen from all the others for the study area because of its large size and the abundance of Pieris . It is located approx imate ly two and one ha lf miles east of Che rokee Orchard .
The Bullhead Tra il in the study area exte nds from 4110 feet to
42 50 feet elevation . The pine-he ath itse lf lies on a south-facing slope , exte nding from the top of the ridge to varying distance s down slope as can be seen in the aerial photograph of the area in Figure
5. At its upper boundary along the trail , the pine -heath me rge s with a he ath bald.
A tota l of forty sets of ne sted square plots was established in a line pa ra lle l to the Bullhe ad Trail . A compa ss wa s used to ma ke adjacent plot edge s parallel. Plots we re space d 50 feet apart .
Twe nty of the plots we re establishe d in disturbed trail edge ve ge tation to te st its effect on Pieris de nsity. The y we re placed adjacent to and with one edge on the trail. A table of random numbe rs was used to de termine on which side of the trail to place them. The large r plots we re .OS acre (46 feet, 8 inche s on a side ) with .02 acre
(31 feet, 7.5 inche s on a side ) and .01 acre (20 feet , 10 .5 inche s on
15 16
a. Study area b. Heath bald c. Open oak d. Cove hardwood
Figure 5. Aerial photograph of Bullhead Trail in the vicinity of the study area.
Source: TVA aerial photograph AOB-15L-91, April 19, 1954. 17
a side ) plots placed in one corne r of each of the .OS acre plots . The
se cond twenty se ts of plots of this same description we re placed at
dis tance s greate r than SO feet from the trail. A table. of random
numbe rs .wa s used·to de termine the distance and direct ion (up or down
slope ) from the trail. A clinome ter wa s used to de te rmine the slope
of each plot and the length of the side s was adjusted accord ingly .
Within each .OS acre plot, the d·.b.h. (diameter at breast he ight) of each tree wa s me asured and it s he ight estimated . The .02 acre ·plot wa s used origina lly to me asure the diameter of the shrub
laye r (at one foot from ground surface) . Be cause of the uniformity
of the shrub laye r, it s samp ling size wa s diminished to .01 acre .
The diamete r of the large st stem, the total numbe r of stems, and the maximum he ight of each shrub was recorded. Be cause of the nature of
the shrub laye r, a smaller plot, one-ha lf the area of the .01 acre
plot, wa s de s ignated to me asure the diameter of every stem present .
All va scular taxa pre sent we re listed and the pe rcentage ground cove r wa s estima ted for the he rbace ous layer in the .01 acre plot .
The numbe r of fruit pe r plant, the numbe r of runne rs pe r plant
and the growth·form, whe ther ve rtical, horizontal or inte rmediate,
wa s also re corded for Pieris .
Soil samples we re taken from six locations within the study
area and the thickne ss of litte r, fe rmentation layer, and humus wa s me asured at each site . The pH of each layer was me asure d with a Lee ds
and Northrup pH me te r us ing a soil to wa te r ratio of one to one
(Jackson, 19S8) . The sample s we re pre pa red and analyzed for calcium, 18 magnes ium, pota ssium, sodium, manganese and zinc content according to the procedure des cribed in Appendix A.
At four sites with in the study area, maximum-m in imum thermometers were placed at three diff erent levels: one foot above the litter, in the litter and at six inches below the litter surface. A prec ipitation ga uge wa s pla ced in a clea r area along the ridge. Rea dings from the se instruments were recorded from October 1966 through September 1967 . . Germination ex periments were conducted with seeds of Pier is which had been col lected in September and October of 1966 from plants in the study area . The ex periments were conducted under controlled tempe rature and photoper iod conditions in the laboratory. The day length wa s set at 16 hour s day l ight and 8 hours da rknes s with the temperature va rying between 74° F. and 76° F.
The seeds were pla ced in petr i plates on mo ist filter paper,
100 seeds per plate. The seeds were stratif ied, two plates being left without stratif ication, and each month therea fter, two addit iona l plates were removed from the cold room and placed under controlled tempe rature and lighting . The cold room wa s kept at 6° C.
A tota l of 131 fruits wa s ex amined and the number of seeds per fruit wa s recorded for ea ch. Forty-five fruits were stud ied micro scopica lly and the number of seeds with viab le embryos wa s noted. III . RES ULTS
I The data conce rning each tree species we re comb ined for plots adjacent to the trail and those located at va rious distance s from the tra il after the Student 's "t " te st at the 95 pe r cent leve 1 of signif i- cance (S teel and Torrie, 1960) showed no sign if icant differences to exist be tween the total basal areas of the se two locations . A summary
I of de nsity of tree taxa by diameter classes may be found in Appendix B.
Frequency of Trees
The fre quency of the spe cies in the tree stratum is shown in
Tab le I, inc luding the frequencies of the se same species unde r 1.0 inch in diameter and as seedlings .
Pinus punge ns is the on ly tree species to exhib it a frequency of 100 pe r cent with Ny ssa sylva tica and Ace r rubrum having the next two highe st frequencie s of 77.5 pe r ce nt and 72 .5 pe r ce nt re spective ly .
The se thre e species also have the highe st frequencies of trees le ss than 1.0 inch in diame te r. Howeve r, the frequency of the se spe cies as seedlings is quite diffe re nt . Ace r rubrum ha s the highe st fre- que ncy of 62 .5 pe r ce nt with Ame lanchie r arbore a and Que rcus prinus having the next highe st freque ncie s.
!lex montana and Viburnum cassinoide s we re found in the two plots closest to the he ath bald at the uppe r exte nt of the pine -heath, and are judged atypica l of pine -he ath stands.
19 20
TABLE I
PER CENT FREQUENCY OF TREE SPECIES IN THE TREE STRATUM, UNDER ONE INCH DIAMETER AND AS SEEDLINGS
Per Cent Frequency Tree Under One Seed- Taxon Stratum Inch D.B.H. lings
Pinus J2Unf2ens 100 .0 42 .5 17.5 Nyssa sylvatica 77.5 45.0 12 .5 Acer rubrum 72 .5 30.0 62 .5 Quercus 12rinus 45.0 12 .5 25 .0 Oxydendrum arboreum 40 .0 5.0 10.0 Robinia 12seudo-acacia 32.5 * 5.0 Hamamelis virginiana 30.0 17. 5 22.5 Castanea dentata 15 .0 17.5 10.0 Tsuf2a canadensis 15 .0 17. 5 20.0 Magnolia fraseri 10 .0 * 5.0 Sassafras albidum 10.0 7.5 15 .0 Betula lent a . 7.5 7. 5 10.0 Arnelanch ier arborea 7.5 10.0 35.0 Halesia carol ina var. monticola 5.0 * * !lex montana 5.0 2.5 * Picea rubra 2.5 2.5 2.5 Quercus rubra 2.5 2.5 15 .0 Faf2us f2randifolia 2.5 * 5.0 Acer 12ens�lvanicum * 10.0 2.5 Quercus velutina * 2. 5 * Clethra acuminata * * 7. 5
*Species absent. 21
Density and Basa l Area of Trees
The me an dens ity and per cent tota l basa l area of the tree spec ies may be found in Tab le II. As can be seen, five spec ies are
the mo st preva lent. Pinus pungens is dominant with Nyssa sy lvatica,
Acer rubrum, Quercus pr inus and Oxydendrum arboreum the next mos t numerous .
The diameter s of the tree spec ies were placed in classes to correspond with ones used by Whit taker (1956) to character ize the growth and su rviva l of trees into the larger size classes in various mo isture gradien ts. A loga rithmic and linea r graph·of tree spec ies
in the Bullhead Tra il pine-heath as compared to the pine-hea th used by Wh ittaker is shown in Figure 6. As can be seen in the figure, 59.6 per cent of the stems in the stand were within the sma lles t size class
(1 .0-3.0 inches) wh ile Wh ittaker found approximately 66 per cent to fa ll within this cla ss . In the size class 16-18 inches, Wh ittaker found approxima tely 0.36 per cent of the stems as compared to 0.16 per cent in the study area . This large number of stems in the sma l ler size classes and sma ll number in the large size classes wou ld imp ly a cont inuous reproduction and replacement in both st ands.
Wh ittaker states that reproduct ion in the pine st ands in the
Smokies is cyclic . Th is periodic reproduction of the stand is indi cated .in Figure 7a by the large number of stems in the sma ll diameter classes and the large number also in the 8, 9, and 10 inch classes for
Pinus pungens . Using these same diameter classes for P. pungens in the study area gives a rather cont inuous decrea se in the number of 22
TABLE II
MEAN DENSITY PER PLOT AND PER CENT TOTAL BASAL AREA OF TREES IN THE STIJDY AREA
Per Cent Total Basal Taxon Density Area
Pinus pungens 44.95 85. 05 Oxydendrum arboreum 17.75 1. 15 Nyssa s2:1vatica 12. 60 5.12 Acer rubrum 3.93 2.75 Hamamelis virginiana 3.60 4(1. 00 Quercus prinus 2. 08 3. 79 Robinia pseudo-acacia Ll.OO Ll.OO Castanea dentata <1.00 ..c1.00 T.suga canadensis <1. 00 <1.00 Magnolia fraseri <1.00 �1.00 Sassafras albidum ..::.1.00 <1. 00 Betula lenta <:1.00 .c::l.OO Amelanchier arborea �1.00 �1. 00 Halesia carolina var. monticolor ..::.1.00 .c.1.00 Ilex montana ..:::1. 00 L.l.00 Viburnum cassinoides <1.00 �1.00
Picea ---rubra <1.00 <1.00 Quercus rubra <-1.00 �1.00 Fa�us �randifolia <1. 00 <1. 00 23
17.0 I 16.0 ' \ Study area 15.0 ' ' ' 14 .0 \ Pine-heath stud ied by \ Whitt�ker · ( 1956) 13 .0 \ \ \
10 .0 9 .0 8 .0 7 .0 6 .0 '0 5 .0 s:: cu � 4.0 rn � 0 3.0 � s:: 11' C) 2.0 � 11' �
1.0 0.9 0.8 0. 7 0.6 0.5
0.4 \ \ 0. 3 \ \ 0.2 \
0.1�----�--��--�----�----�----�'��---- 1� 4- . 7- . 10- ' 13- 16- 19- 22- 3.9 6.9 9.9 12 .9 15.9 18 .9 21.9 24 .9 Diameter classes (inches)
Figure 6. A comparison of diameter distribution of all stem s in two pine-heath stands: the study area and a stand investigated by Whittaker (1956) . 24
500
(b) (a) en s
200 0 1 Diameter in inche s
en s
C. Ka lmia latifolia had a 100 per cent frequency in the shrub stratum.
Rhododendrum maximum, Va ccinium sp. and Pier is floribunda had fre quenc ies of 75.0, 85 .0, and 72 .5 per cent respectively. The dens ity of these shru bs was ca lculated by us ing the mean number of stem s wit hin plot s and not the number of clumps of the spec ies. Th is was thought to be a bet ter es tima te becaus e it was diff icu lt at times to distinguish one clump from another . Pieris floribunda had the highest dens ity of 97 .5 stems per plot . Va ccinium sp. had a dens ity of 32.6,
Ka lm ia latifolia, 86.6 and Rhododendrum max imum, 3.2 .
Herbaceou s Cover
The taxa cont ribut ing to the herbaceous cover and their fre quencies are lis ted in Ta ble III . Such taxa as Aster sp ., Gerardia flava, Andropogon scoparius, Ha benaria ciliaris and Solidago sp. were found to be present on ly along the edge of the tr ail. Epigaea repens,
Ga lax aphylla and Ga ulther ia procumbens were the mos t preva lent taxa. 26
TABLE III
SPECIES PRESENT AND THEIR FREQUENCY IN THE HERBACEOUS COVER
Taxon Frequency
Andropogon scoparius 12.5 Aster sp. 2.5 Chimaphila maculata 5.0 Epigaea repens 95.0 Galax aphylla 92.5 Gaultheria procumbens 90.0 Gerardia flava 10.0 Habenaria ciliaris 5.0 Lycopodium obscururn 40.0 Medeola virginiana 12.5 Melarnpyrum lineare 40.0 Monotropa uniflora 2.5 Pteridium aquilinurn 55.0 Solidago sp. 22.5 Trillium undulaturn 12.5 Vaccinium sp. 45,0 27
The most nume rous liche ns in the study area we re Ce traria tucke rmanii, Pa rme lia caperata, Pseudevernia consocians, Alectoria bicolor and Usnea comosa.
Pieris flor ibunda
The Student's "t .. te st at the 95 pe r ce nt leve l of significance wa s used to te st the significance be tween the me asurements re c orde d for Pie ris floribunda in plots adjacent to and off the trail. No sig nif icant diffe rence wa s found for.the tota l numbe r of stems nor the numbe r of fruits pe r plant be tween the se two areas . The data there fore we re comb ined as be fore . Howe ver , a highly significant differe nce wa s found be tween the ave rage diame te rs in the se two areas . The ave rage stem diameter in plots off the trail wa s 0.62 inch wh ile in plots along the trail, the ave rage stem diameter was 0.45. The ave rage numbe r of runne rs pe r plant wa s found to be significant ly diffe rent at the 80 pe r ce nt leve 1 of sign ificance . The ave rage numbe r of runne rs wa s
8.13 for plots off the trail and an ave rage numbe r of 5.59 for plots along the trail . The standard deviation and range of each of the se me ans may be found in Tab le IV .
From fruit colle cted along the Bullhe ad Trail in the fall of
1966, it wa s found that the re is an ave rage of 32.2 seeds pe r fruit,
20.9 of the se ha ving fully deve loped embryos . The standard de viation and range of the se me ans may be found in Table IV also. In the field, it wa s de te rm ined that Pieris had an ave rage of 59.4 fruit pe r plant .
It may be concluded from this that one Pie ris plant would probably have 28
TABlE IV
THE MEA N, STANDARD DEVI ATION AND RANGE OF SEVERAL CHARACTERS OF PI ERI S FIDRIBUNDA
Standard X Deviation Range
Off trail plots diameter 0. 62 0. 62 0.1-3.0 in .
Number of runners 8.13 8.94 0-50
On trail plots diameter 0.45 0.40 0.1-2 .0 in.
Number of runners 5.9 10 .15 0-50
Number seeds/fruit 32 .2 4. 12 23-43
Number seeds with developed emb ryos 20 .9 3.46 14-2 7 29 approximate ly 1242 seeds wi th fully deve loped embryos . From this it may be deduced that one acre of thi s pine-he ath shou ld produce approx imate ly twe lve mi llion Pie ri s seeds with fully forme d embryos . Ye t on ly one seed ling pe r acre was found in the samp ling .
Ge rmination experiments conducted in the laboratory with the se seeds gave the followi ng re sults: 17 .5 pe r cent ge rmination for those wi thout stratification , and 20.0 pe r cent ge rmination for those wi th one month cold treatment. During the se cond month of stratification , the seeds be gan germinating in the cold room . The se we re remove d from the cold room and a 19 .7 pe r ce nt ge rmination was obtained.
Envi ronmental Study
The maximum tempe rature s re corded at the five stations in the study area we re ave raged for each time pe riod for each of the three leve ls ( one foot , li tter , and soil) to give one maximum temperature for the study area for that time inte rva l. Thi s was also done for the minimum tempe rature s and the re sults are shown in Figure 8 and
Figure 9.
The air temperatures we re the most ext reme of the three as wou ld be expe cted. The maximum tempe rature for the soil, litter and ai r was re corded during the same time period for all three . For the per iod of Apri l 1, 196 7 to Ap ri l 8, 1967 , 66 .0° F. , 86 .0° F. , and 90. 3°
F. we re recorde d for soil, litte r and air re spective ly. The minimum tempe rature for the litter and air was registered be tween February 11,
196 7 and Apri l 1, 196 7. The litter re ache d a low of 18 .0° F. and the ioo
90 . /'.,..' r:t...... ' 0 80 "\. ' t: ' . .... '\.--- 70 QJ '/ 5-.4 � •••• . ::l ...... / . .. • ...... � : ... . •• . . ctJ / .• :60 ,�/ � • 5-.4 .... ······ v . .. ····· ' . .. • ...... v � • •••• 8 ·-so . . QJ •• ••• E-4 ---- 1 foot leve 1 ··- ··· ·····•···. · -----Litter 40 ···,·····S oi l
Day Month 10 11 4 5 6 8 Year.. .1966 Time
Figure 8. Ave rage maximum temperatures for five stations in study area for the one foot leve 1, litte r, and soil.
w 0 ••• ...... �, �, ...... , -�·· � , ...... · � . ... ········ ··•· . ······ � / - 0
s:: ·� (l) � ::J - .;' I � - ----· /"....._ ...... � ...... I 20 -- � ...... � 8 (l) E-4 1 foot le ve 1 . ----- Litte r
• • • • • • • Soil
Day. :.24 28 r Month 10 11 12 1 4 Ye ar 1966 1967 Time
Figure 9. Average minimum tempera tures for five stations in study area for the one foot le ve l, litte r, and soil.
w ...... 32 air tempe rature fe ll to -9.4° F. The soil re a che d its minimum tempe r ature of 32 .0° F. du ring the pe riod from Nove mbe r 29, 1966 to De ce mbe r 9,
1966.
The air tempera ture s for the study area which we re ob taine d by averaging the maximum re adings and the minimum readings se parate ly from the five stations for each time pe r iod are compa re d to the tempe r ature s from two othe r locations in the Pa rk, Ne wfound Ga p and Pa rk He ad qua rte rs, in Figu re 10 and Figure 11. The maximum te mpe rature and the min imum tempe rature for each time pe r iod for the se two locations we re ob tained from the da ily maxima and the da ily minima. Ne wfound Gap is at an elevation of 5046 feet wh ile the Pa rk He a dqua rte rs station is
1400 feet above sea le ve l. The pine -he ath tempe rature s ge ne ra lly range d be tween those for the othe r two localitie s. The minimum temp erature s more ne arly coincided for the three areas than the maximum temperature s. It shou ld be noted that the maximum tempe rature during th is pe riod from Octobe r 24, 1966 to Septembe r 11, 1967 wa s 90.3° F., re corded in the Bullhe ad pine -he ath .
In Figure s 12 and 13, the maximum and minimum air tempe rature s discussed above for the study area are compared with those of Ne wfound
Gap and Pa rk He adquarters. For each group of points, a le ast square s fit wa s obtained. Regre ssion statistics appear in Tab le V.
It can be seen in the table and graphs that the maximum tempe r ature s for the Bullhead pine -heath are highe r than those for Ne wfound
Gap but are lowe r than those for Pa rk He adquarte rs. An increase of one de gree at eithe r site me ans an incre ase of slight ly le ss than one ,...... Cl.! � 0 _ _ _ I ' - r:: ' _ ,...... ) , _ ___ ' ' __ / ' , - / -- � .• / . . .. • . . • . . ::s / . . • ...... •• • . • +J / ••• .'• .. . . . • • . .. cu • . � • . .. · Q) v . . � . , ...: / · s .. . •• •, . � •• .. • . ·. .. • •. . : . • . .. ,• • • ••• .. .. • Pa rk Headquar.ters _____, -----.Study area
' • ....- • , , Newfound Gap ' Day 1 8 29 14 18 1 11 20 2 18 11 Month 4 5 6 7 8 9 Year _ _ Time
· · Figure 10 . Compa·· rison of average maximum temperatures for three area s in Great:Smoky ·· Mountains· National Pa rk! Pa rk Headquarters, study area, and Newfound Gap .
(...) (...) 70
60
. � so
0
c I ,.- -. _. -...... 4Q ClJ � ::s � 30 ctJ � � 20 a ClJ E-t 10 "' . ·-- '· •• ,. • ••• •. • o J • .. • ,. '� � Park He adquarte rs ------study area • .. -10-l • � •• • • • • • Newfound Gap
Day 242136 20 29 9 Month 10 11 1 6 ·Ye ar 1966 1967 Time
Figure 11. Comparison of ave rage minimum temperature s for thre.e areas in Gre at Smoky Mountains National Park: Park He adquarte rs , study area, and Newfound Gap .
w -1=" 35
0 90 (a)
; 60 Q) s... tV 1\ = �50 Y 0. 88 X + 18.8 "0 =' +-J Cl.l
Newfound Gap, �emperature, oF.
••
.. 50 (b) • • r.. • 0 40 •
Q) s... =' 30 +-J tV s... 20 • 8.e Q) +-J 10
tV Q) s... ctl 0 � "0 1\ =' = +-J -10 y 0.86 X + 8.1 Cl.l
-10 0 10 20 30 40 50 Newfound Gap, .tempe_.ature, 0 F.
Figure 12. Re·1ation of Newfound Gap and study area maximum (a) and minimum (b) temperatures. 36
0 (a)
� 60 � cu
1\ Y = 0 . 7 S X + 12 . 8
so 60 70 80 90
Park Headquarters, temperature, ° F.
60
tJ;.. so (b) 0
• Q) � 40 ;:j � cu � 30 8. 8 Q) . � 20 •
cu Q) � 10 cu >. 'tJ 0 ;:j " � Y = l.OS X .... 3. 6 en •
0 10 20 30 40 so 60 Pa rk Headqua rters, temper ature, ° F.
Figure 13. Relation of Pa rk Headquarters and study area maximum (a) and minimum (b) temperatures . 37
TABLE V
VALUES OF COMPONENTS OF REGRESSION EQUATIONS OF TEMPE�TURES
y X A b r
Minimum
Pine -heath Newfound Gap 8.1 0.86 0.93
Pine -heath Park He adqua rters -3.6 1.05 0.97
Maximum
Pine -heath Newfound Gap 18.8 0.88 . 0.90
Pine -he ath Park He adquarters 12.18 0.75 0.84 38
degree on the Bullhead. The minimum tempe ratures of the study area are
lower than those of Park Headquarters and have practica lly a one to one
slope. The minima for the pine-hea th are higher than those for the
Newfound Gap station , and change at slight ly les s than a one to one
rate.
The cumulative rainfa ll for these same three locations is shown
in Figure 14 for November 6, 1966 through September 11, 1967. Newfound
Gap, with over 80 inches of rainfall for this eleven month period, had
not quite tw ice the amount of precipitation as the pine-heath on Mt .
LeConte. Park Headquarters had slight ly over 50 inches , still above
the 47 inches received in the gauge in the pine-hea th.
Of the soil samples taken from the study area , samples one and two are from sites close to the point of transition from pine-heath
to hea th bald; samples three and four are from the pine-heath; samples five and six are from the lower edge of the pine-heath near the trail , sample six being closes t to the oak forest.
McGinnis (1958) des cribed a soil profile for a tab le mountain pine stand in Cades Cove in the Grea t Smoky Mountains Na tional Pa rk at an elevation of 2800 feet with a shrub cover composed of ericaceous plants. A comparison of McGinnis ' profile with those from the Bullhead
Tra il pine-heath appears in Tab le VI.
The results of the analysis of the soil samples taken from the study area are shown in Tab le VII. Chemical analysis was not conducted on the A00 horizon . 90 ---- Newfound Gap
• • •. • • • Pa rk Headqua rters
80 ------· Study are a
70 CIJ Q) .c g 60 ..... c: .... •••• . so • � ...... ••• ••••••• � . � . 40 ...... /� _.....,._ ...... c: ...... · ...... �� ca .. ...,., • 0:: 30 . ... ; /' .,.. �----., ...... � :;..o' 20 . ..---· .... -.,.·- - 10 ••• • ••• ��---;;...... ••• ·· - "'1i"• �·... �n
Day 1'4 Month 1 4 Year 1967 Time
Figure 14 . A comparison of the cumulative rainfall for three locations in Great Smoky Mountains Na tional Pa rk: Newf ound Gap, study area� and Park Headquarters .
w \0 40
TAB lE VI
SOI L PROFi lES AND pH VA LUES FROM THE BULUIEAD TRAI L PI NE -HEATH AND A PI NE -HEATH AT 2800 FEET ElEVATION STUDIED BY McGI NNIS
Thickness in em. pH Horizon Study Area McGinnis S tudy Area
Aoo Sample 1 2. 5 1. 1 4.5 2 0. 6 4. 7 3 0. 5 4.9 4 0. 5 4. 8 5 0. 5 4. 5 6 0. 5 4. 7
F Sample 1 6. 3 0. 5 3. 7 2 6. 3 3. 4 3 12. 6 3.7 4 6. 3 3. 8 5 7. 6 3.8 6 6. 3 3. 5 a H Sample 1 a 1. 2 2 23. 4 3. 1 3 5. 1 3. 7 4 0.6 4. 2 5 0. 3 4.5 6 12. 6 3. 3 b A l Sample 1 4. 4 2 a 3 4. 6 4 . 4. 8 5 4.8 6 4.7
aHorizon not present in sample.
bNot measured. 41
TAB lE VI I
AVAi lABlE CATIONS OF SOliS IN THE STUDY AREA
a a a ga b b Horizon K N==a Ca M Mn zn
F Sample 1 0.87 0.00 5.27 1.78 0.02 1.48 2 4. 79 4.82 1.67 5. 72 0.00 5. 15 3 0.00 2.90 5.55 1.29 0.00 4. 58 4 0.87 4. 17 2 . 22 0.36 0.07 2. 70 5 1.31 0.30 3.61 2.85 0.00 4.38 6 0.44 7.41 16.10 0.36 0.01 3.35
H . Sample 1 c 2 0.00 11.28 1.39 1.43 0.00 2.25 3 4.37 2.57 1.39 0. 72 0. 00 <0.01 4 1.74 2.26 1.39 1.29 0.05 0. 10 5 3.05 1.61 1.39 1.29 0.00 <0.01 6 0.00 3. 8 7 22 .77 0.00 0.00 0.20
Al Samp le 1 5. 68 13.54 3. 33 0. 72 0.00 BExpre ssed in me q . /100 g. �xpre ssed in p.p.m. CHorizon not pre se nt in samp le . dLost du ring analysis . 42 The pH of the F horizon range d from 3.4 to 3.8. In ge neral, the acidity incre ased from the A00 to the F horizon and be gan to de crease from the H to the A 1 . The thic kne ss of the humus wa s the greatest (23.4 em .) for the sample taken adjacent to the he ath bald . Litt le work has be en done on the chemica l ana lys is of soi ls of pine -he ath stands . McGinnis found a conce ntration of 0.98 and 3.80 meq . for potassium and ca lcium , re spective ly , in the H hori zon . The pH was 3 . 8, not too different from that found in the study area. For the A1 , he found potassium to have a concentration of 0.45 me q . and calcium , 0.70 me q. The pH wa s 4. 1, lowe r than the pH for the A 1 in any of the samp le s from the Bul lhead Trail pine -heath . IV. DISCUSSION AND CONCLUSI ONS It is to be expe cted that a pine-he ath wou ld occupy the south and southwe st facing slope s of the mountains of the Smokies . The se areas are both the mos t xe ric and the most extreme with respect to tempe rature in comparison to othe r areas at comparab le elevations . The soil tempe rature s show less seasonal variation than the tempe rature s of the air and litter. This is to be expected be cause the soil functions as an insulator , re taining he at longe r and conse quently staying at a more cons tant tempe rature throughout the year. The tempe rature s of the litter (Figure 8, page 30 , and Figure 9, page 31) are more close ly aligned to those of the air than the soil , but still not as extreme as those of the air. The temperature of the litter wa s cons ide red important be cause it is he re that the seeds of Pie ris ove r winte r and the scarcity of seedlings wa s quite obvious. The only locat ion whe re Pie ris was found to have seedl ings was adjacent to the trail and then on ly in a ve ry small numbe r. Any extreme temperature s in this area could possibly influe nce the numbe r of seedlings present . Freezing . temperature s immediate ly after ge rmin ation of the seedling :cou ld kill the new seedling . Since no dormancy pe riod was observed in the ge rmination of the seeds , it is pos sible that the se seeds might ge rm inate during warm pe riods in the winter and subsequent ly be killed by the re turn of free zing tempe ratures . It shou ld be noted he re that seeds which we re stratified for two months in the laboratory began ge rminating while still unde r the se 43 44 conditions . However, the resulting seed lings were not subjected to freezing temperatures so the ex act effects cannot be stated with cer tainty . Anothe r critical factor in Pieris seed germination is the amount of rainfall rece ived during the winter in the se pine -heath commun it ies . Pine -hea ths are notably xeric habitats, and the amount of rainfall re ceived for the winter months falls be low tha t re ceived at the Pa rk Headquarters we a ther sta tion . The seeds used in the ge rm ination ex periments in the laboratory were kept mo is t for the dur ation of . their stratif ication so aga in it cannot be shown with evidence that des icca tion wou ld injure the seeds, but it seems a good pos sibility of being a cont ributing factor . The soi ls in wh ich Pieris was growing were diverse with res pe ct to the thickness of the first three hor izons . In compa rison to the soil prof ile of the pine-heath reported by McGinn is (1958) , the hori zon s in the study area are cons ide rably dee per . The pine-he ath which McGinnis inve stiga te d was at an eleva t ion of 2800 fe et, sugges ting wa rmer tempe ratures than those of the Bul lhead Tra il pine -hea th . With these lowe r tempe rature s on the Bul lhea d, the accumu lation of litter and undecomposed ma terial shou ld increase be cause of a lowe r rate and shorte r season of decompos ition . The humus and A 1 were not as a who le more acidic than those of the othe r pine -he�th . The grea ter acidity of soils is thought to slow the rate of decompos ition . The pine-heath on the Bul lhead Tra il is very similar to the he ath bald de scribed by McCracken et al. (1962) with respe ct to its 45 low fertility of ca lcium and potassium . Manganese was almost entirely absent from the samples . A high concentration of zinc occurs in the F layer and decreases gradua lly until it almost disappears in the A 1 horizon, but the amount in the F horizon is still lower than the amount norma lly found in soils (S wa ine, 1955) . According to Wh ittaker, this pine-hea th stand shou ld be mainta in ing itself when compa red to the pine-hea th he studied shown in Figu re 6, page 23. Approx ima tely 59 per cent of the tota l number of stems in the stand fell within the 1-3 inch diameter class as compa red to approximately 66 per cent for the stand studied by Wh ittaker. There are in actua lity two tree layers in the Bul lhead Trail pine-hea th, the higher composed of the ma ture pines and the lower layer of dec iduous trees . The frequency of the dec iduous trees in the tree stratum, four spec ies having over 40 per cent frequency (Nys sa sylvatica, Acer rubrum, Quercus prinus and Oxydendrum arboreum) may indicate the inva s ion of the pine-heath by the forests of lower ele vations . The frequency of pine seedlings and those under one inch in diameter is qu ite not iceably sma l ler than the 100 per cent frequency ob served for the mature trees . The dec iduous species have a high fre quency as seed l ings relative to pine but their frequency decreases as they reach sapling size . This is a reversal of what one would expect in a stand wh ich is ma intain ing itself. One wou ld ex pect a grea ter frequency of the dominant species as seedl ings than the others, thes e being pine and the dec iduous spec ies respect ively. The pine-heath is relatively open ex cept for the shrub stratum which is quite dense and 46 continuous throughout. The de nseness of the se shrubs could be a major factor in the maintenance of the pine -heath by diminishing the amount of light which re aches the ground . The light intensity is so low that it cou ld ke ep pine seedlings from be coming established . If this we re true , the numbe r of pine s would slow ly decre ase and the pine-he ath wou ld eventually become a he ath bald . Howe ve r, there is a high fre quency of de ciduous seedling s in the area. As more and more de ciduous trees be come established , the ir shade would cause the numbe r of he ath shrubs beneath them to diminish and it wou ld eventua lly be come a part of the oak forest of lowe r elevations . Whittaker (1956) cons ide rs the pine -heath a topographic climax and use s as evide nce the bimodal size -class freque ncy curve shown in Figure 7, page 24. The same frequency curve for the Bullhe ad Trail pine -he ath doe s not give a bimodal freque ncy curve . While Cain (1937) thought tha t fires in the se pine -he aths he lp pe rpe tuate the dominance of pine , the figure me nt ioned above ind ica te s that this pine -heath ha s had a rather uninte rrupte d growth and re production for a conside rable pe riod . Since this stand ha s re ma ined undisturbed for what appears to be a long time , one wou ld expect it to be invaded by both the he ath ba ld and oak forest species. It seems much more like ly at the pre sent that this particular pine -heath may eventually be come a he ath ba ld be cause of the de nse ericaceous shrub layer already pre sent and the low surv iva l rate of de ciduous seedlings . With a low ge rm ination rate in the laboratory and the almost comple te absence of seed lings in the pine -heath, a fre quency of 72 .5 47 pe r cent and a density of 97.5 for Pie ris we re not to be expected . Howeve r, with an ave rage of five to eight runne rs pe r plant , Pieris is able to ke ep its high degree of cove rage in this area. It repro duces ve ge tative ly by runne rs and by layering. A significant diffe rence wa s found be tween the diameters and numbe r of runne rs of Pie ris from the two locations of plots , but not be tween any othe r characte ristics of Pieris investigated. The differ ence in diameters and numbe r of runne rs cou ld easily be a function of the age of the plant , those off the trail having been establ ished be fore the trail was cut about thirty years ago. More experiments with the seeds of Pieris are ne cessary to be ab le to show the effects of environmental extreme s as are encountered in an area such as this pine-heath. A comparison of such factors as soils and tempe rature extremes of the Bullhead Trail pine -heath and anothe r location of Pieris as the one s in North Carolina along the Blue Ridge Pa rkway would more than like ly give the answer to many questions still unanswe red about Pieris . Although no conclusive evi dence ha s been pre sented he re , it is still thought that the creation of a dis turbance area is one of the major factors in the establ ishment of Pieris . Afte r estab lishment , Pie ris may continue to ma intain itse lf and even incre ase its cove rage by vegetative re production . V. SUMMARY The role of Pieris floribunda Benth . and Hook . in a pine-hea th community in the Great Smoky Mountains Nationa l Pa rk was studied. The pine-heath was loca ted on the Bullhead of Mt . LeConte at an elev ation of approximately 4100 feet . Forty .05 acre plots were es tabl ished for sampling stand charac teristics and to tes t for dif ferences between Pieris and its surround ings along the trail and Pier is growing in dense shrub cover off the trail. The diameters and number of stems were recorded for both trees and shrubs in addit ion to a specie s list of the herbaceous cover. Special not es were made for Pier is with res pect to number of runner s and numb er of fruits per plant . Germination ex periments were conducted with seeds of Pier is col lected in the study area the previou s fa ll. Pieris was found to have 20 .0 per cent germination under laboratory conditions . The pine-hea th along the Bullhead Tra il is a typical one with respect to environment and veget ationa l compos ition . Its . seasonal maximum and minimum temperatures are more extreme than the lower ele vations yet not as ex treme as the higher elevations in the Pa rk . By use of the derived regression equations, the maximum or minimum temper atures of the pine-hea th may be predicted from either the maximum or minimum temperatures at Pa rk Headqua rters or Newfound Gap . The amount of rainfa ll rece ived in the pine-hea th is lower than that of both Newfound Ga p and Pa rk Headqua rters . 48 49 It is thought that this pa rticular pine -heath is be ing invaded by the he ath bald located at its uppe r limit and will eventually be come a he ath bald if fire does not pe rpetuate the pine-heath . No significant diffe rence was found be tween the two locati ons of plot s with re spect to the density of Pieris , and the re f ore it cannot be concluded that Pie ris require s a disturbance or break in the canopy to be come establ ished. Howe ver, it is still thought that furthe r study may prove this to be true . LITERATURE Cl TED LITERATURE CITED As sociation of Agricultural Chemists . 1945 . (Ed . 6) . Officia l and tentative me thods of ana lysis of the Association of Official Agr i cultura l Chemists . Washington , D. C. Bailey, L. H. 1930 . The standard . cyclopedia of horticulture . The Macmillan Co. , New York. 3 vols . Cain, S. A. 1930 . Certain floristic affinit ies of the trees and shrubs of the Great Smoky Mountains and vicinity. Butler Univ . Bot . Stud. 1:129-150 . 193la . An ecological study of the he ath ba lds of the Gre at Smoky Mountains . Butler Univ . Bot. Stud . 1:177-208. 193lb. Ecological studie s of the ve ge tation of the Great Smoky Mountains of North Carolina and Tenne ssee. I. Soil reaction and plant distribution . Bot . Gaz. 91:22-41 . 1937. A pre liminary guide to the Greenbrier-Brushy Mountain Na ture Trail, the Great Smoky Mountains Na tional Pa rk. Botany De pt. , Univ . Te nn . (mime ographed) . Cooper, A. W. 1963. A survey of the ve getation of the Toxaway Rive r Gorge with some remarks about early botanica l explorations and an annotated list of the vascula r plant s of the gorge area . J. Elisha Mitche ll Sci. Soc. 79(1): 1-22 . Davis , J. H. 1930 . Ve ge tation of the Black Mountains of North Caro lina : an ecological study . J. Elisha Mitche ll Sci. Soc. 45 :291- 318. Fernald , M. L. 1950 . Gray 's Manua l of Bot any . 8th ed . Amer. Book Co. , New York. 1632 + lxiv pp . Hadley , J. B., and R. Goldsmith . 1963. Geology of the Eastern Gre at Smoky Mountains of North Carolina and Tennessee . Ge ological Surve y Professiona l Pape r 349-B . U. S. Gov't. Printing Office , Washing ton , D. C. Jackson , M. L. 1958. Soil chemical analysis . Prentice -Hall, Inc. , N. J. 498 + xiv pp . Lems , K. 1962 . Ad apt ive radiation in the Ericace ae . I. Shoot de ve lopme nt in the Andromede ae . Ecology 43 : 524-528. 51 52 Li , Hui-Lin . 1952 . Floristic re lationships be tween eastern Asia and eastern North America . Trans . Amer. Ph il . Soc. 42 : 371-429. McCracken , R. J. , R. E. Sha nks , and E. E. C. Clebsch . 1962 . Soil morphology and ge ne sis at highe r elevations of the Great Smoky Mountains . Soil Sci. Soc. Am . Proc . 26:384-388 . McG innis , J. T. 1958 . Fore st litter and humus type s of East Tennessee . Master's thesis . The University of Tennessee , Knoxville . Pa lser, Barbara F. 1951. Stud ie s of flora l morphology in the Ericales . I. Organography and vascular anatomy in the And romedeae . Bot . Ga z. 112 :447-485 . 1952 . Studie s of floral morphology in the Ericales. II . Me gas poroge ne sis and me gagametophyte deve lopme nt in the And ro medeae . Bot . Gaz. 114 :33-52 . Racine , C. H. 1966. Pine communities and the ir site characte ristics in the Blue Ridge Escarpment . J. Elishn Mitche ll Sci. Soc . 82 (2) :172-181. Ramseur , G. S. 1960 . The va scular flora of high mountain communit ie s of the Southe rn Appa lachians . J. Elisha Mit che ll Sci. Soc. 76:82- 112 . Rodgers , C. L. 1965. The ve ge tation of Horsepasture Gorge . J. Elisha Mitche ll Sci. Soc. 81 : 103-112 . Sha nks , R. E. 1954 . Clima te s of the Great Smoky Mountains. Ecology 35 : 354-361. Steel, R. G. 1 and J. H. Torrie . 1960 . Pr inciple s and procedure s of statistics . McGraw-Hill Book Co. , New York . 481 + xvi pp . Swaine , D. J. 1955. The trace-e lement content of soils . Commonwe alth Agricultura l Bureaux , Eng l and . 157 + viii pp . Tanner, J. T. 1963 . Mountain tempera ture s in the Southeastern and Southwe stern United States during late spring and early summer. J. of Applied Me teorology 2(4) :473-483. Thornthwa ite , C. W. 1948 . The clima te s of North Ame rica accord ing to a new classification . Geogr . Re v. 21(4) : 633-655 . Whittaker, R. H. 1956. Ve ge tat ion of the Great Smoky Mountains . . Ecol. Monog . 26: 1-80 . 53 1966 . Forest dimens ions and production in the Grea t Smoky Mount ains . Ecology 47 (1):10 3- 121. Wi lliams, R. H., and H. J. Oost ing . 1944 . The vegetation of Pilot Mountain, North Ca ro l ina: A _ community ana lys is . Bull. Torrey Bot. Club 71:23-45 . Wood, C. E. 1961 . The genera of Ericaceae in the Southea stern United States. J. Arnold Arboretum 42 : 10-80 . APPENDIXES APPENDIX A PROCEDURE FOR THE PRE PARATION OF SOIL SAMPlES All samples we re air dried and pa ssed through a 2 mm . sieve . Te n gram sample s we re we ighe d and placed in 250 ml . glass stoppe re d flasks . Fifty ml . of norma l ammon ium acetate adjusted to pH 7.0 , by adding ace tic acid or ammonium hydrox ide as ne cesspry , was added and the flask was shaken in a me chanical shaker for one ha lf hour. The flasks and contents we re allowe d to stand ove rnight . Ce rtain samp le s Filte ring of the le a chings was carried out through a Whatman No . 42 filter unde r vacuum . The re s idue in the flasks was washed with SO ml . of ammonium ace tate divided into three portions . Each portion was used to wash the re s idue on the filter taking care to le t each port ion pass through the filter bef ore add ing anothe r. The filtrate s we re transfe rred to evaporating dishes and evap orated on a ste am bath as ne arly dry as possible (sample s with con side rable or ganic matte r re sisted going to dryne ss on the steam bath) . Three ml . of norma l HN0 3 and 5 ml . H202 we re added to the re si due s and dige sted on the ste am bath unt il dry . Th is was repeated unt il a clear colorless solution re sulted . (Trace s of iron le nt a slight ly ye llow color to some samp les.) 55 56 The re s idue s we re dissolve d in a little doub le distilled wa ter and transferred to 250 ml . vo lume tric flasks . Doub le distilled water was used to ma ke up to volume . Cations we re ana lyzed in suitable aliquots according to pro cedure s out lined in the sixth edit ion of the A. 0. A. C. under the se c tion on analys is of plants . Blanks we re run for each cation and cor re ct ions made if ne cessary. APPENDIX B SUMMARY OF TREE TAXA IN DIAMETER CL\SSES BY PIDT Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13.6- 16.6- 19.6- No . Taxa 3.5 7.5 10 .5 13.5 16.5 19.5 22 .6 1 Acer rubrum 3 Ame lanchie r arborea 1 Betula lenta 2 !lex mo� 7 Nys sa sylvatica 56 7 Oxydendrum arboreum 1 Picea rubra 1 . Pinus pungens 1 4 1 Viburnum cassinoide s 5 V1 ...... 2 Acer rubrum 2 4 Ame lanchie r arbore a 2 Betula lenta 1 1 !lex montana 1 Nyssa sylvatica 32 9 Oxydendrum arboreum 1 Pinus pungens 1 4 7 8 Robinia pseudo-aca cia 2 3 Viburnum cassinoides 5 3 Acer rubrum . 4 3 Nyssa sylvatica 6 4 Oxydendrum arboreum 13 3 2 Pinus pungens 7 6 2 1 Rob inia pseudo-acacia 1 1 Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13. 6- 16.6- 19.6- No . Taxa 3.5 7.5 10 .5 13.5 16.5 19 .5 22 .6 4 Nyssa sylvatica 9 1 Oxydendrum arbore um 2 Pinus pungens 13 3 5 2 1 5 Acer rubrum 2 Ame lanchie r arbore a 1 Nys sa sylvatica 11 Oxydendrum arboreum 8 Pinus pungens 9 16 12 1 Tsuga canadens is 1 1 6 Acer rubrum 8 Nys sa sylvatica 29 Pinus pungens 18 12 11 3 1 7 Nys sa sylvatica 10 Oxydendrum arboreum 1 Pinus pungens 17 12 2 2 2 Tsuga canadens is 1 8 Nys sa sylvatica 1 Pinus pungens 9 23 6 9 Ny ssa sy1vatica 2 Pinus punge ns 8 11 6 3 Tsuga canadens is 1 10 Nyssa sy1vatica 2 Pinus pungens 12 16 7 5 1 V1 00 11 Acer rubrum 3 Pinus pungens 1 11 9 1 . Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13.6- 16.6- 19 .6- No . Taxa 3.5 7.5 10 .5 13.5 16.5 19 .5 22.6 12 Pinus pungens 83 13 3 13 Pinus pungens 66 18 4 14 Acer rubrum 1 Ny ssa sylvatica 5 Pinus pungens 28 4 5 3 Quercus prinus 1 Rob in ia pseudo-acacia 1 15 Nyssa sylvatica 4 Pinus pungens 94 37 2 Que rcus prinus 1 1 16 Ace r rubrum 6 Ny ssa sylva tica 7 Pinus pungens 41 16 2 Que rcus prinus 8 1 Rob inia £Seudo-acacia 1 17 Acer rubrum 8 2 Betula lenta 1 Hamame lis virgin iana 5 Magnolia fraseri 1 Ny s sa sylvatica 32 1 Pinus pungens 2 1 Que rcus· prinus 1 3 2 Robini� £Seudo-acacia 1 l8 Acer rubrum 3 VI Nyssa sylvatica 2 \0 Pinus punge ns 6 22 8 1 Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13.6- 16.6- 19.6- No . Taxa 3.5 7.5 10 .5 13. 5 16.5 19.5 22.6 19 Acer rubrum 1 Nyssa sylvatica 1 Que rcus prinus 2 Pinus pungens 39 9 5 4 20 Acer rubrum 9 1 Hamame lis virginiana 10 Nys sa sylvatica 11 1 · Pinus pungens 1 1 Quercus prinus 4 3 2 2 Robinia pseudo-acacia 3 2 21 Acer rubrum 2 Oxydendrum arbore um 4 Que rcus prinus 3 Pinus pungens 5 23 11 4 22 Nyssa sylvatica 3 · Pinus pungens 49 45 5 Robinia pseudo-acacia 2 23 Sassafras albidum 1 Pinus punge ns so 9 7 24 Pinus pungens 16 16 25 Acer rubrum 6 castanea dentata 1 Hamame lis virginiana 18 Nyssa sylvatica 13 0\ Oxydendrum arboreum 1 0 Pinus pungens 34 17 6 1 Que rcus prinus 3 Robinia pseudo-acacia 1 Diameter Classes Plot 1- 3. 6- 7.6- 10.6- 13. 6- 16. 6- 19. 6- No . Taxa 3.5 7.5 10 .5 13. 5 16.5 19. 5 22 .6 26 Acer rubrum 2 Castanea dentata 1 Ny ssa sylvatica 2 Pinus pungens 38 6 7 2 27 Acer rubrum 8 1 Castanea de ntata 1 Hamame lis virginiana 15 Ny ssa sylvatica 28 Oxydendrum arbore um 2 3 Pinus punge ns 1 2 4 1 Que reus prinus 2 1 2 Robinia pseudo-acacia 1 2 8 Acer rubrum 2 Nyssa sylvatica 7 Oxydendrum arboreum 1 Pinus pungens 1 4 3 1 1 29 Acer rubrum 16 3 Hale's ia carolina 1 Hamame lis virginiana 11 Ny ssa sylvatica 31 2 Pinus pungens 4 2 4 3 1 Que reus prinus 5 2 1 Sassafras albidum 3 1 30 Ace r rubrum 9 5 1 Hamame lis virginiana 21 Nyssa sylvatica 21 3 0\ . Oxydendrum arbore um 12 6 ...... Pinus pungens 3 3 Que rcus prinus 2 4 Diameter Classes Plot 1- 3.6- 7.5- 10 .6- 13. 6- 16. 6- 19 .6- No . Taxa 3.5 7.5 10 . 5 13.5 16.5 19.5 22 .6 Q. rubra 2 Sassafras albidum 2 . Tsuga canadensis 1 31 Acer rubrum 1 2 2 Halesia carolina 1 4 Hamame lis virginiana 14 Magnolia frase ri .2 Nys sa sylvatica 18 5 . Oxydendrum arboreum 1 1 Pinus pungens 8 2 Quercus prinus 6 3 5 Robinia pseudo-acacia 1 32 Acer rubrum 2 Oxydendrum arbore um 2 Pinus punge ns 5 12 5 5 1 33 Acer rubrum 3 2 3 Ca stanea dentata 1 Hamamelis virginiana 14 Magnolia fraseri 8 1 Ny ssa sylvatica 38 13 . Oxydendrum arboreum 4 Pinus pungens 1 2 Quercus prinus 1 Robinia pseudo-acacia 2 1 Sassafras albidum 1 34 Acer rubrum 1 . Ca stanea dentata 1 0\ N Oxydendrum arbore um 12 Pinus pungens . 72 5 5 2 2 Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13.6- 16.6- 19 .6- No . Taxa 3.5 7.5 10 .5 13. 5 16.5 19 .5 22 .6 35 Acer rubrum 10 1 Castanea dentata 2 Hamame lis virginiana 15 Magnolia frase ri 1 Ny s sa sylvatica 20 Oxydendrum arboreum 2 Pinus pungens 24 6 2 1 Que rcus prinus 1 3 Tsuga canadens is 1 36 Ace r rubrum 2 Ny s sa sylvatica 8 Pinus pungens 56 23 1 2 Rob inia £Seudo-acacia 2 37 Acer rubrum 2 Hamame lis virginiana 3 Nyssa sylvatica 10 _ Pinus pungens 40 29 1 1 Que reus prinus 2 Robinia £Seudo-acacia 1 38 Acer rubrum 1 Hamame lis virginiana 12 Pinus pungens 77 14 3 1 39 Ace r rubrum 7 Fagus grandifolia 1 Hamame lis virginiana 6 Nys sa sylvatica 22 . Pinu s pungens 34 44 2 2 1 � w Diameter Classes Plot 1- 3.6- 7.6- 10 .6- 13. 6- 16.6- 19.6- No . Taxa 3.5 7.5 10 .5 13.5 16.5 19.5 22 .6 40 Acer rubrum 2 Nyssa sylvatica 11 Oxydendrum arboreum 1 Pinus punge ns 52 30 2 1 Que rcus prinus 5 0\ .J:" APPENDIX C SUMMARY OF SHRUB TAXA IN DIAMETER ClASSES BY PI.DT Diame te r Classes Plot .1- .69- 1.27- 1.85- 2.43- No . Taxa .68 1.2 6 1.84 2.42 3.00 1 Ka lmia latifolia 3 9 2 Pie r is flor ibunda 1 Rhodode ndron maximum 4 2 4 3 2 Ka lmia latifolia 10 14 Vaccinium sp. 29 3 Ka lmia latifolia 1 1 Va ccinium sp . 7 4 Ka lmia latifolia 15 8 5 2 Pieris floribunda 9 1 Rhododendron max imum 16 2 Va ccinium sp. 3 3 5 Ka lm ia latifolia 17 14 7 Pier is floribunda 2 1 6 Ka lmia latifolia 16 4 6 3 Pie r is flor ibunda 15 Va ccinium sp. 3 7 Ka lmia latifolia 15 9 1 Va ccinium sp. 30 8 Ka lmia latifolia 13 10 1 Rhododendron maximum 1 2 1 9 Ka lmia latifolia 42 13 Va ccinium sp. 21 10 Ka lmia latifolia 25 17 3 Va ccinium sp. 1 8 11 Ka lmia latifolia 11 17 2 Pie r is floribunda 2 1 1 1 65 66 · Diameter Classes Plot . 1- .69- 1.2 7- 1. 85- 2.43- No . Taxa .68 1.26 1.84 2.42 3.00 12 Ka lmia latifolia 27 20 Pier is floribunda 2 8 5 1 Va ccinium sp. 17 13 Ka lm ia latifolia 27 3 Va ccinium sp. 25 14 Ka lmia latifolia 28 2 Va ccinium sp. 24 15 Ka lmia latifolia 12 3 Pieris floribunda 7 3 2 1 1 Va ccinium sp . 18 16 Ka lmia latifolia 21 1 Pieris floribunda 40 4 Rhodode nd ron maximum 1 17 Ka lmia latifolia 9 4 Pieris floribunda 29 5 1 Va ccinium sp. 26 18 Ka lmia latifolia 4 1 Pieris floribunda 10 2 Rhododend ron maximum 13 3 1 4 1 19 Ka lmia latifolia 33 7 Pieris floribunda 11 3 1 Va ccinium sp. 5 20 Ka lm ia latifolia 13 8 Pieris floribunda 3 Va ccinium sp. 24 21 Ka lmia latifolia 6 1 Pieris floribund a 10 2 1 3 Rhododend ron maximum 3 22 Ka lmia latifolia 9 5 Pieris floribunda 26 9 Vaccinium sp . 4 23 Ka lmia latifolia 15 7 Va ccinium sp. 21 67 Diameter Classes Plot .1- .69- 1. 27- 1.85- 2.43- No . Taxa .68 1.26 1.84 2.42 3.00 24 Ka lmia latifolia 52 3 Pie r is floribunda 7 · 1 Va ccinium sp. 12 25 Ka lmia latifolia 6 7 2 1 Pie ris flor ibunda 1 2 2 Vaccinium sp. 28 26 Ka lmia latifolia 3 12 2 Rhododendron maximum 6 1 1 1 27 Ka lmia latifolia 10 2 2 Pie ris floribunda 5 Vaccinium sp. 9 28 Ka lmia latifolia 1 14 4 Vaccinium sp. 7 29 Ka lmia latifolia 5 5 3 Pieris flor ibunda 3 1 2 Vaccinium sp. 1 30 Ka lmia latifolia 7 5 1 1 Rhododendron maximum 12 4 1 31 Ka lmia latifolia 1 5 1 Vaccinium sp. 1 32 Ka lmia latifolia 9 12 3 33 Ka lmia latifolia 14 26 3 34 Ka lmia latifolia 8 11 3 1 Vaccinium sp. 2 35 Ka lmia latifolia 37 7 Vaccinium sp. 32 36 Ka lmia latifolia 17 12 Pieris floribunda 7 3 2 1 Va ccinium sp. 5 37 Ka lmia latifolia 4 10 3 Pieris floribunda 8 68 Diameter Classe s Plot .1- .69- 1. 27- 1.85- 2.4 3- No . Taxa .68 1.26 1.84 2.42 3.00 38 Kalmia latifolia 22 48 5 Pieris f l oribunda 20 8 5 1 39 Kalmia latifolia 46 18 1 Vaccinium sp. 17 40 Kalmia latifolia 21 4 1