Distribution of Roots and 

Rhizomes in Different Soil 

Types in the Pine Barrens 

of New Jersey

GEOLOGICAL SURVEY PROFESSIONAL PAPER 563-C

Prepared in cooperation with the New Jersey 

Department of Conservation and Economic 

Development^ Division of Water Policy and 

Supply; Rutgers University; and the U. S. 

Forest Service
Distribution of Roots and 

Rhizomes in Different Soil 

Types in the Pine Barrens 

of New Jersey

By WILLIAM A. LAYCOCK

HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

GEOLOGICAL SURVEY PROFESSIONAL PAPER 563-C

Prepared in cooperation with the New Jersey 

Department of Conservation and Economic 

Development, Division of Water Policy and 

Supply; Rutgers University; and the U. S. 

Forest Service

UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1967
UNITED STATES DEPARTMENT OF THE INTERIOR 

STEW ART L. UDALL, Secretary

GEOLOGICAL SURVEY 

William T. Pecora, Director

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 - Price 30 cents (paper cover)
CONTENTS

Definition of botanical terms__ 

Abstract__. ________________

Introduction. _____________________________

Purpose and scope_------______-______.

Acknowledgments. _____________________

Location and general features of the area. 

Previous studies.______________________

Methods used to study root systems. 

Root and rhizome systems. _ 

Vertical distribution of roots- _ _

Root and rhizome systems___________________________

Roots and rhizomes of the most common shrubs-__- 

Upland shrubs____________________________

Gaylussacia baccata (black huckleberry)____

Vaccimum vacillans (lowbush blueberry) 

Quercus ilicifolia (scrub oak)_____________

Quercus marilandica (blackjack oak)_______

Quercus prinoides (dwarf chestnut oak) _ _ _ _

Gaultheria procumbens (teaberry)__________

Transition zone shrubs._____________________

Kalmia angustifolia (sheep laurel)-_---____

Clethra alnifoUa (sweet pepperbush) _______

Lyonia mariana (staggerbush) ____________

Gaylussacia frondosa (dangleberry)________

Myrica pensylvanica (bayberry)___________

Ilex glabra (inkberry)____________________

Roots and rhizomes of less common shrubs_________

Kalmia latifolia (mountain-laurel)___________

Hudsonia ericoides (golden heather) and Leiophyllum buxifolium (sand myrtle) ___________

Lyonia liguslrina (maleberry)_______________

Comptonia peregrina var. asplenifolia (sweet 

fern) ____________________________________

Vaccinium angustifolium (low sweet blueberry) _

Amelanchier canadensis (serviceberry) and Pyrus

melanocarpa (black chokeberry)___________

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Underground rhiz ome growing tips ________________ Cll

Seedlings ___________-__-_-_____--_----_-_---_-- 11

Relation of root distribution to different soil types. _____ 11

Soil profiles.----------------------------------- 11

Lakewood sand 9706._.______________ 12

Lakewood sand, clay substratum variant 9A16- 12

Downer sand, leached phase 9E16.__________ 14

Lakeland sand, leached A2 phase 9Y16_______ 14

Lakehurst sand 9726___________________ 14

Lakehurst sand, thick A2 variant (grading toward Leon sand)________________________ 15

Leon sand 9736__________________ ._ 15

Additional sites: Lakewood sand 9706__ ______ 15

Additional site: Leon sand 9736_____________ 16

Development of roots.__________________________ 16

Number and area of roots in the profile-_______ 16

Number and area of roots in the various

horizons._ ______________________-_-----_- 17

AQ horizon.___-___-_---_-------_---_--- 17

AI horizon.-_---_----_----------------_ 17

A2 horizon_____________________________ 18

BI horizon._-_------_-----------------_ 18

B2 and other lower horizons._____________ 19

Distribution of roots in different vegetation

types _____-_-____-___-_______---_----- 19

Distribution of roots in 6-inch layers___-____-_ 19

Distribution of roots of different sizes and types. 20

Roots of different sizes._________________ 20

Roots of different types__________________ 20

Effect of decaying roots in the soil._______________ 21

Effect of soil texture on root distribution. _________ 21

Relation of root distribution to the water table.________ 22

Effects of fire---..--------------------------------- 24

Effects on roots and rhizomes_______-__-__-__--_- 24

Effects on ground-water supplies__________________ 24

Summary. __________________---_-_-__-____-----_-_- 26

Selected references._________________________________ 27
IV CONTENTS 

ILLUSTRATIONS

Page 

FIGURE 1. Map of New Jersey showing the Pine Barrens and area of this report________________________________ C2

2-4. Photograph-of 

2. The rhizome system of Gaylussacia baccaia-- __________________________________________________ 5

3. The Vaccinium vacillans root-______________________________________________________________ 6

4. A Quercus ilicifolia taproot_______-__--____-_------_-__------_______________________________ 6

5. Diagram of the different types of root systems of Quercus ilicifolia- ____________________________________ 7

6-10. Photograph of 

6. A Kalmia angustifolia root__ ________________________________________________________________ 8

7. A Clethra alnifolia rhizome. _ ________________________________________________________________ 8

8. The top view of a Lyonia mariana clone_____________________________________________________ 8

9. A Lyonia mariana root____i______________-___-__________--________-_______________________ 9

10. The root stock and larger roots of Kalmia latifolia.... __________________________________________ 10

11. Diagram of root systems of Hudsonia ericoides and Leiophyllum buxifolium. _____________________________ 10

12. Photograph of an extensive rhizome system of Lyonia fo'gwsinr_a__--------___-_---_____________________ 10

13. Graph showing the comparison of the number and area of roots per square foot in profiles of the different

soil types______________________________ ________________-_____________________________________ 18

TABLES

Page 

TABLE 1. Mechanical analysis and permeability data of the soils studied -.-----_-____-_----------_-__---------- C13

2. Presence and abundance of trees and shrubs immediately surrounding the soil pit in each soil type-_________ 13

3. Actual number of roots and number and total cross-sectional area of roots per square foot of vertical profile

in each horizon and in the entire profile--____________________-_-_-________--_-_-_-_-_-_---------__ 16

4. Analysis-of-variance computations for determining differences between the number of roots per square foot

in the entire profile among the various soil types._____________--_-__-______-_-_------____--__-_--__ 17

5. Results of multiple-range test comparing the average number of roots in the entire profile and in each horizon

and the average area of roots in the entire profile among the seven soils having comparable vegetation __ 17

6. Percentage of total number and area of all roots in the profile found in the A0 and At horizons._____________ 18

7. Results of multiple-range test comparing the average number of roots in the entire profile and in each horizon 

and the average area of roots in the entire profile among the three Lakewood sand sites supporting different 

vegetation. ___--____________________________-_________-____--____-____-___---__-___-.-___----_- 19

8. Total number of roots and number of roots per square foot in each 6-inch layer of the soil profiles. _________ 20

9. Number of shrub, pine, and oak roots more than 0.2 inch in diameter in the A0-Ai horizons and in the entire

profile. _-__-_______-_-_____________________-_-___-_____-_------_-______--_-__--------------_-_ 21

10. Average number of shrub, pine, and oak roots more than 0.2 inch in diameter in five soil types having oakpine vegetation and a good shrub cover and in three soil types having only pine and shrub vegetation____ _ 21

11. Relation of roots of the Pine Barrens shrubs to the water table.-______________________________________ 23

12. The effect of the July 1955 wildfire on the shrub cover.____________________________________________ 24

13. Scientific and common names of plants of the Pine Barrens mentioned in the paper_____________________ 25

14. Summary of the characteristics of the root and rhizome systems of the Pine Barrens shrubs studied._______ 26
DEFINITIONS OF BOTANICAL TERMS

Definitions of botanical terms used in this paper are based

mainly on Eames and MacDaniels (1947) and Fuller and Tippo

(1954).

Aerenchyma : In a physiological sense, any loose aerating tissue.

Aerial stem: A stem that grows above the soil (see "rhizome").

Axillary bud: A bud borne in the axil of a leaf. The axillary 

buds of a rhizome originate in the axils of the scale leaves 

on the rhizome growing tips.

Cambium : Layer of meristematic cells between secondary xylem 

and secondary phloem tissue that contributes new cells to 

both.

Clone: A population resulting from vegetative (asexual) reproduction of a single individual.

Internode: The length of stem between two successive nodes.

Lateral roots: Branch roots that arise from a primary root 

system or taproot.

Meristematic tissue: A tissue whose cells are capable of frequent division and which is thus responsible for the first 

phase of growth.

Node : The part of a stem from which a leaf and a bud arise.

Nodule: On the roots of certain plants, an enlargement within 

which nitrogen-fixing bacteria or fungi live.

Parenchyma rays: Narrow vertically elongated bands of parenchyma cells that extend radially in stems from the pith 

through the xylem and in some stems through the phloem.

Perennating bud: A terminal or axillary structure on a stem 

or rhizome consisting of a small mass of meristematic tissue 

and often covered by protective scales. The part of a plant 

from which new stem growth originates.

Phloem : A plant tissue, consisting primarily of sieve cells, sieve 

tube cells, and phloem parenchyma, that conducts food in 

the plant. In woody stems and roots the phloem generally 

is outside the xylem'.

Pith: The parenchyma occupying the central part of the stem 

inside the xylem.

Rhizome: A horizontal underground stem, often rooting at the 

nodes. Rhizomes may resemble roots superficially; however, they are true stems with nodes, internodes, buds, and 

often leaves.

Rhizome growing tip: The underground nonwoody terminal 

part of actively growing rhizomes that continues the elongation of the rhizome. See section on "Underground Rhizome 

Growing Tips" (p. Cll) for a more detailed description.

Root : That part of the axis of most plants that is nongreen and 

grows beneath the surface of the soil. Roots lack the nodes, 

internodes, and leaves that are characteristic of stems. The 

principal functions of roots are absorption of water and dissolved minerals, anchorage, conduction of material, storage 

of food, and vegetative reproduction.

Rootstock: A rhizome. In the plants Kalmia latifolia and 

Lyonia mariana, an enlarged underground woody structure 

from which both roots and aerial stems arise.

Root system : The entire mass of roots produced by a plant.

Roots, fibrous: Nonwoody roots.

Roots, woody: Roots whose main bulk is secondary xylem 

(wood).

Scale leaves: Reduced, nongreen leaves.

Stem : That part of the plant axis consisting of nodes and internodes and bearing leaves and often reproductive structures. 

(See "aerial stem" and "rhizome.")

Taproot: A stout vertical root that continues the main axis of 

some plants. Taproots of woody plants generally are larger 

than the other roots and extend rather deep into the soil.

Xylem : A complex plant tissue, consisting of vessels, tracheids, 

and other cells, that conducts water and dissolved salts in 

the plant. Wood is composed of secondary xylem.

HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

DISTRIBUTION OF ROOTS AND RHIZOMES IN DIFFERENT SOIL TYPES IN THE

PINE BARRENS OF NEW JERSEY

By WILLIAM A. LAYCOCK

ABSTRACT

The Pine Barrens, which consists of upland forests and 

lowland swamps, covers approximately 2,000 square miles of the 

Coastal Plain of New Jersey. The root and rhizome systems 

of selected shrubs of this region were studied as part of the 

New Jersey Pine Barrens Hydrologic research project to determine the effects on the present and future ground-water supplies 

of changes in forest composition caused by controlled burning.

The form, depth, and lateral extent of the root and rhizome 

systems of 20 species of shrubs which grow in the upland forest 

and in the transition zone between the upland and lowland 

areas of the region are described. Two species of shrubs 

(Kalmia angustifolia and Lyonia mariana) in the transition 

zone have phreatophytic characteristics. The roots of these two 

species penetrate as deep as 40-58 inches to reach the underlying 

water table. Roots of the other species of shrubs may or may 

not extend to the water table.

The Ao soil horizon contains the highest number of tree and 

shrub roots per square foot, and the Ai horizon contains the 

next highest number. In upland soils, numbers of roots decrease 

sharply from the Ai to the A2 horizon, increase slightly in the Bi 

horizon, and then decrease with depth below the Bi horizon. 

The increase in the Bi .horizon does not occur in the poorly 

drained soils. The highest total numbers of roots in the entire 

profile were found in soils having thin, imperfectly leached 

A3 horizons.

Sites with shrubs had significantly more roots, especially in 

the Ao and Ai horizons, than similar sites having no shrubs. A 

decrease in shrub cover caused by controlled burning, and the 

resultant decrease in roots, might permit more water to reach 

the water table.

INTRODUCTION

The study reported here is part of the New Jersey 

Pine Barrens hydrologic research project, begun in 

1951 as a phase of the cooperative program of the U.S. 

Geological Survey and the New Jersey Department of 

Conservation and Economic Development, Division of 

Water Policy and Supply. Other cooperating agencies 

include Kutgers, The State University of New Jersey; 

the Northeastern Forest Experiment Station of the 

U.S. Forest Service; and several local organizations. 

The hydrologic research project was started to determine the effect of changes in forest composition caused

by controlled burning 011 the present and future groundwater supplies of the area. Two small watersheds in 

the Lebanon State Forest, New Jersey McDonalds 

Branch watershed (1,480 acres) and Middle Branch 

watershed (1,590 acres) were selected as study areas. 

Kecording gaging stations were placed at the mouth 

of each watershed. A network of observation wells was 

established on each watershed, and a rain-gage network 

was installed to include the watershed areas. After a 

period of calibration, one of the watersheds will be 

subjected to controlled burning, and the other will be 

kept free from fire. A wildfire in 1955 burned about 

450 acres of the eastern end of McDonalds Branch 

watershed (McCormick, 1955) so an extended period 

of calibration may be needed before changes in silvicultural practices can be started.

PURPOSE AND SCOPE

The purpose of the present study was to determine 

(1) the form, depth, and lateral extent of the root and 

rhizome systems of the upland and transition-zone 

shrubs of the region and (2) the vertical distribution 

of roots of trees and shrubs in different soil types found 

in the uplands and the transition zones of the two 

experimental watersheds. Transition zone is used in 

this paper to designate the zone between the upland and 

lowland areas. The water table in the transition zone 

is about 2-5 feet below the surface most of the year, and 

the characteristic plant community is the pine transition community described by McCormick (1955). The 

most common soil types in the transition zone are the 

Leon sand and the Lakehurst sand, thick A* variant.

Knowledge of the characteristics and distribution of 

root and rhizome systems of shrubs is important in 

watershed management. Because only a small amount 

of overland flow occurs in the Pine Barrens, shrub roots 

are less important in soil stabilization and erosion 

prevention than in areas where these factors are prob01
C2 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

lems. However, a dense stand of shrubs undoubtedly 

absorbs and removes large amounts of water from the 

soil. The density of shrubs in upland areas in this 

region is greatly reduced by controlled burning (Little 

and Moore, 1945). This reduction or any other factor 

that decreases the number or changes the distribution 

of roots in the soil may increase the amount of water 

available to meet transpirational requirements of other 

vegetation or to replenish the ground-water reservoir. 

A fuller knowledge of the characteristics of the roots 

of the shrubs may also lead to methods of controlling 

shrub density.

ACKNOWLEDGMENTS

Special thanks are due Murray F. Buell, professor of 

botany at Rutgers, The State University of New Jersey, 

for his advice, assistance, and encouragement. For 

their many courtesies and assistance in this study, the 

writer wishes to thank Alien Sinnott, E. C. Khodehamel, 

Seymour Subitzky, and other members of the staff of 

the Ground Water Branch district office, Trenton, N. J., 

and H. C. Barksdale, branch area chief, Atlantic Coast 

Area.

LOCATION AND GENERAL FEATURES OF THE AREA

The Pine Barrens of New Jersey consists of about 

2,000 square miles of woodland on the Coastal Plain in 

the southeastern part of the State (fig. 1). 

4' The upland vegetation of the region consists of 

Various mixtures of oak (white oak, Quercus alba 1 ', 

black oak, Q. velutina; chestnut oak, Q. prinus; and 

others), pine (pitch pine, Pinus rigida; and shortleaf 

pine, P. echinata) , and scrub oak ( Q, tticifolia). The 

lowland plant communities include dense southern 

white cedar swamps (Chamaecyparis thy aides) ^ hardwood swamps (red maple, Acer rubrum var. trilobwn; 

black gum, Nyssa Byl/vatica; and others), and pitch pine 

lowlands (McCormick, 1955; Little and Moore, 1953).

The history of the region is one of recurrent fires and 

and repeated and extensive disturbance by man. Fires 

have kept most forest stands on a 25- to 50-year cycle 

since 1800 or earlier (Little and Moore, 1945). The 

forests have been cut frequently since the 17th century 

to supply wood for nearby cities, steamships, and railroads as well as for various local industries, such as bogiron works, glass making, and charcoaling (Cranmer, 

1952; McCormick, 1955).

Because of the prevalence of wildfires, many of the upland forest stands consist of oaks of sprout origin mixed 

with pine (Little and Moore, 1945). These stands produce little timber and consequently have little commercial value (Moore, 1939). Light controlled winter

1 Nomenclature of all plant species follows Fernald (1950).

fires remove most of the litter creating seed-bed conditions favorable for pine reproduction (Little and 

Moore, 1945; Little and others, 1948; and Little, 1953). 

Larger pines are fire resistant and survive these controlled fires, but the above-ground parts of most of the 

associated oaks are killed. Subsequent cutting of the 

oak sprouts and burning at intervals result in almost 

pure stands of pine, which are more valuable than mixed 

stands. This controlled burning also reduces the occurrence and damage of wildfires (Moore and others, 

1955).

Lebanon State 

Forest boundary

20 MILES 

J

FIGURE 1. Map of New Jersey showing the Pine Barrens (after 

Harshberger, 1916) and the area of this report.
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C3

The principal geologic formation underlying the Pine 

Barrens is the Cohansey Sand of Miocene (?) and Pliocene (?) age. Along the west and northwest, however, 

the Pine Barrens are underlain by the upper beds of 

the Kirkwood Formation of Miocene age (Tedrow, 

1952). Except for a few lenses of clay in the Cohansey 

Sand, both formations are composed of quartz sands and 

gravels in thin outcrop areas (Kiimmel, 1940). Several discontinuous younger deposits of sand and gravel 

(Beacon Hill gravel, and Bridgeton, Pensauken, and 

Cape May Formations) occur in the region (Kummel,

1940).

The thick sandy strata that underlie the Pine Barrens have been proposed as a future source of water 

because they form a large natural reservoir with a possible specific yield of about 20 percent of their volume 

(Barksdale, 1952). The average annual precipitation 

in the region is slightly more than 45 inches (White,

1941), and very little runs off as overland flow because 

of the highly permeable sandy soil and gentle slopes 

characteristic of the region. Barksdale (1952) estimated that about 20 inches of the annual rainfall would 

be available for water supply and that more than a billion gallons per day could be pumped from these formations by a network of wells without depleting the storage in the reservoir below its annual recharge potential.

Because the sandy strata underlying the Pine Barrens may be important for future water supplies, it is 

desirable to know which plants are phreatophytes 

plants whose roots extend either to the water table or 

to the capillary fringe above the water table, and thus 

insure a more definite and continuous supply of water 

for the plants (Meinzer, 1927). Phreatophytes have 

been studied mainly in the arid parts of the Western 

United States. Eobinson (1951, 1958) stated that 

phreatophytes cover about 16 million acres in the 17 

Western States and may release 20-25 million acre-feet 

of water into the atmosphere annually. Studies of 

phreatophytes in the Eastern United States include the 

work of Hoover (1944), Dunford and Fletcher (1947), 

Trousdell and Hoover (1954), and Hewlett and Hibbert (1961) who determined the effects of removing 

trees and streambank vegetation on streamflow and 

water-table level in North Carolina.

The amount of ground water now being used by 

phreatophytes in the New Jersey Pine Barrens is probably not important because there is little demand for 

this water, but as the water becomes more essential to 

the economy of the region, the use of water by 

phreatophytes may have to be reduced.

PREVIOUS STUDIES

Many workers have studies plant ecology and silvicultural methods in the New Jersey Pine Barrens. So 

far as known, the earliest comprehensive report which 

describes the forest conditions in the region was prepared by Pinchot (1899). Stone (1912) studied the 

flora and Harshberger (1916) studied the ecology of 

the region. In recent years, other papers concerning 

special problems on plant ecology and the effects of 

controlled burning on the vegetation in the general area 

of the present study have been published by Buell and 

Cantlon (1950, 1953), Cantlon (1951), Buell (1955b), 

and Moul and Buell (1955). A vegetation map and a 

detailed description of the plant communities on the 

two watershed areas was prepared by McCormick 

(1955). Bacho (1955) mapped the surficial geology of 

the two watersheds, and Markley (1955) described and 

mapped the soils.

The root and rhizome systems of some of the Pine 

Barrens shrubs have been described by the following 

writers: Comptonia peregrina var. asplenifolia and 

Myrlca pensylvanica ( Youngken, 1919; Hall and Mack, 

1960); Ilex glabra (Holm, 1929), and Vaccinium angustifolimn (Hall, 1957). Coville (1910) and Mahlstede and Watson (1952) studied the roots of V. corymbosum, and Braun (1936) described the roots of 7. verticillata. Both species are found in lowland areas in

the Pine Barrens but were not included in the present?

w study. *?

' Harshberger (1916) described the roots of many New* 

Jersey Pine Barrens species, including most of those 

studied in the present report. His descriptions tend to 

be superficial but as far as they go they are correct, with 

the exception of Hudsonia ericoides and Leiophyllum 

~buxifolium. These two species are discussed on page 

CIO.

The root systems of many species of Pine Barrens 

trees also have been studied previously. Some of these 

studies should be mentioned here even though the present study did not include any trees. McQuilkin (1935) 

studied the root systems of pitch pine and shortleaf pine 

in the Pine Barrens, and Stout (1956) studied the root 

systems of chestnut oak, white oak, and red maple in 

New York.

METHODS USED TO STUDY ROOT SYSTEMS 

ROOT AND RHIZOME SYSTEMS

Various methods of excavating root systems were 

tried during the study. Hand excavation of root systems from the side of a pit as described by Weaver

225-469 O 6e
C4 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

(1919,1920) and Hey ward (1933) was tried but found 

to be unsatisfactory because it did not accurately depict 

the lateral extent of the rhizome system of most of the 

shrubs. Exposing root systems by removing the soil 

from the sides of a pit with a stream of water (Stoeckeler and Kleunder, 1938; Tharp and Muller, 1940) was 

also tried and abandoned for the same reason. An 

attempt was made to remove the soil from the root systems with a stream of water, starting from the surface 

of the soil instead of the face of a pit (Cheyney, 1929, 

1932; Preston, 1942), but this method also failed because 

of insufficient water pressure.

The method finally adopted is almost the same as 

the one used by Cannon (1911), Chadwick, Bushey, and 

Fletcher (1937), Duncan (1941), and Specht and Ratson (1957). It consisted of digging with hand tools, 

starting from the surface of the ground and working 

downward. The soil was removed from the roots and 

rhizomes with a small trowel and a shovel. The horizontal and vertical extent of the roots was drawn to 

scale on graph paper, and the diameters of roots and 

rhizomes, the presence and distribution of small woody 

or fibrous roots, and other pertinent data were recorded. 

Representative root systems of each species were photographed in place or on a white board having a 6- 

inch grid to show the scale. At each site where shrub 

roots were excavated, the characteristics and dimensions 

of the soil horizons were recorded, and various relations 

of root distribution to the soil horizons were noted. In 

areas that have a shallow water table, the position of the 

roots in relation to the water table was recorded.

VERTICAL DISTRIBUTION OF ROOTS

Root distribution studies were made in each of seven 

upland and transition-zone soil types (see p. 11). At 

least one site in each soil type was studied in a pine or 

mixed oak-pine forest stand with a good understory of 

shrubs. Additional sites with no shrub cover were 

studied in the major upland soil (Lakewood sand) and 

transition-zone soil (Leoii sand) to determine the effect 

of different forest types and the presence or absence of 

shrubs on number and distribution of roots. The primary site in Lakewood sand was in an oak-pine stand 

with a good understory of shrubs. Root distribution in 

this soil was also studied at two additional sites in a pure 

pine stand; one site had a good shrub cover and one 

had no shrubs. For comparison purposes, these three 

sites will be referred to as the oak, the pine-shrub, and 

the pine-shrubless sites of the Lakewood sand. The 

primary site in the Leon sand was in a pure pine stand 

having a good shrub understory. One other site in this 

soi] was studied in a turf bald area in a pine stand with

no shrubs. This site will be referred to as the Leon sand 

turf bald site.

The method used to study root distribution was the 

same as described by Scully (1942). A 4- by 4-foot soil 

pit, 4 feet deep, was dug at each site. The pits were so 

located that each wall was 10 feet or more from the 

nearest tree trunk. Exposed roots on a 3-foot-wide 

section in the center of all four walls were counted 

and charted on graph paper to the depth of the pit. A 

1-square-foot frame, divided into 3-inch squares, was 

used to subdivide the wall and to facilitate the counting 

of roots. The frame was placed on each square foot of 

the pit starting from the surface. Within each square 

foot the soil horizons were drawn to scale on graph 

paper and the roots were exposed, counted, and charted 

according to the following diameter classes: 0.01-0.05 

inches, 0.06-0.10, 0.21-0.30, 0.31-0.40, 0.41-0.50, 0.51- 

0.60, 0.61-0.70, 0.71-0.80, 0.81-0.90, 0.90-1.00, and more 

than 1.00 inch. Roots more than 0.2 inch in diameter 

were identified as oak, pine, or shrub roots, but no 

distinction was made between shrub roots and rhizomes. 

The relative abundance of tree and shrub species 

immediately surrounding the pit was also recorded.

Counts on each of the four sides of the pit at each site 

were considered as independent observations. The average numbers of roots per square foot for the entire profile for each of the seven soil types were compared using 

an analysis of variance. An F value was calculated to 

determine whether variation in numbers of roots between soil types was greater than variation within types 

(Snedecor, 1956). If the computed F was significant, 

at the 5-percent probability level, the differences between the various means were tested for significance by 

the multiple-range test described by Duncan (1955).

The mean number of roots per square foot in the A15 

A2 , and B horizons in the various soil types were compared by the same method. No statistical comparison 

between sites was made of the roots in the A0 and Bx 

horizons because these horizons were rather thin or not 

present in all the soil types. However, roots in these 

horizons were included in the profile totals and the roots 

in the B 1 horizon were included in the figures for the 

total B horizon. Accurate counts of the smallest woody 

roots (0.01-0.05 inch) were difficult to make in the A0 

horizon because of the many very small fibrous roots 

intermingled with the humus.

The median value of each diameter class was used to 

compute average area in that class. This average area 

multiplied by the number of roots in each horizon and 

in the entire profile gave the exposed cross-sectional area 

of roots. Differences in the mean area of roots per 

square foot in the profile among the various soil types 

were compared statistically as just described.
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C5

In addition to the root-distribution studies, soil 

samples were collected from each soil pit with a U.S. 

Geological Survey sampler (Smith and Stallman, 1955). 

Relatively undisturbed vertical samples were obtained 

in sections of clear plastic tubing 6 inches long and 2 

inches in diameter. At each site continuous samples 

Avere taken from the top of the mineral soil to the lower 

limit of the root-study pit except in thick and homogeneous horizons for which one or two samples were considered to be representative of the entire horizon. Coefficients of permeability for each sample Avere obtained by 

the A7 ariable-head and constant-head permeameter methods (Wenzel, 1942; Smith and Stallman, 1955) by the 

U.S. Geological Survey hydrological laboratory, DenA^er, Colo. The percentages of the different grades of 

sand and gravel in the samples Avere determined by 

Aveight analysis of particles separated out by sieves, and 

the combined percentages of silt and clay particles were 

determined by the hydrometer method. Particles were 

divided into the folloAving size classes: clay, less than 

0.004 mm; silt, 0.004-0.0625 mm; very fine sand, 0.0625- 

0.125 mm; fine sand, 0.125-0.25 mm; medium sand, 0.25- 

0.5 mm; coarse sand, 0.5-1.0 mm; very coarse sand, 1.0- 

2.0 mm; gravel, greater than 2.0 mm.

ROOT AND RHIZOME SYSTEMS

Root systems of each species studied Avere excavated 

to determine the distribution and most common form of 

the roots and rhizomes. Only the shrubs of the upland 

zone and transition zone communities are described. 

Some of the species studied also occur in the loAvland 

zone communities, but the species that occur only in 

loAvland areas Avere not studied. The relative abundance 

of each species, determined from field observations and 

from data on shrub coA^er given by McCormick (1955), 

are described by the terms "very abundant," "abundant," "common," "rare," and "very rare." Plant community names folloAv the classification given by McCormick. The scientific and common names of plants 

mentioned in this report are given in table 13 (p. 25).

Buell and Cantlon (1953) found that frequent controlled burning reduced cover of Gaylussacia baccata 

more than Vacciniwn vacillans. Special attention Avas 

giA^en to the roots and rhizomes of these species to determine Avhy they differ in ability to recover after burning.

BOOTS AND RHIZOMES OF THE MOST 

COMMON SHRUBS

UPLAND SHRUBS

GAYLUSSACIA BACCATA (BLACK HUCKLEBERRY)

Black huckleberry is abundant in all upland communities, common in the pine loAvland and pine transition 

communities, and common in the cedar SAvamp and hardAvood SAvamp communities. Se\7eral aerial stems arise 

from an extensi\7 ely branched rhizome system (fig. 2). 

In areas ha\7 ing an A0 horizon the rhizome usually is 

partly in this layer and partly in the top inch of the A± 

horizon, but in areas ha\7ing no A0 horizon the rhizome is 

in the top 2-3 inches of the mineral soil (A± horizon). 

The diameter of the rhizome usually is }4-% incn but 

may be as much as 2 inches. Indi\7 idual short roots 

occur all along the rhizome, and on some rhizomes there 

is a cluster of fibrous roots around the base of each aerial 

stem in the A0 horizon or the top part of the A! horizon. 

Larger roots as much as 2 feet long originate near a fork 

of the rhizome or near the base of an aerial stem. These 

roots usually are confined to the A0 or A! horizons, but 

they sometimes extend as deep as 8 inches. The characteristics of the root and rhizome system of Gaylussacia 

toccata and the other shrubs studied are summarized in 

table 14 (p. 26).

FIGURE 2. Part of a much-branched rhizome system of Gaylussacia taccata.

VACCINIUM VACILLANS (LOWBUSH BLUEBERRY)

Lowbush blueberry is abundant in the upland communities, common in the pine transition community, 

and rare in the loAvland communities. Several to many 

aerial stems, connected by an extensive branching 

rhizome, arise a feAv inches to seA^eral feet apart. The 

rhizome is %-% inch in diameter and is usually found 

in the top 2 inches of the A! horizon, but some occur as 

deeps as 6 inches. Unlike the rhizome of Gaylussacia 

baccata, the rhizome of Vaccinium vacillans seldom 

occurs in the A0 horizon, e\7en Avhere this horizon is Avell 

developed. A feAv small roots are scattered along the 

rhizome, and dense clusters of fine short fibrous or 

Avoody roots occur at the base of the aerial stems. A 

Avell-deA7eloped root may arise near the base of an aerial 

stem or near the fork of a rhizome (fig. 3) and may ex-
C6 HYDEOLOGY AND ECOLOGY, PINE BAEEENS, NEW JEESEY

tend as deep as 25 inches; a few reach a depth of about 

48 inches. The top part of this type of root and the part 

of the rhizome from which it grows may be nearly 2 

inches in diameter, but the root tapers rapidly and is 

much-branched near the end. In areas where the water 

table is near the surface, any well-developed roots that 

are present extend horizontally instead of vertically, 

and the finely branched end parts may be in the A0 

horizon.

FIGURE 3. A root of Vaccinium vacillans that extended 13 inches 

deep into the soil, then branched, both branches extending 

horizontally in the Bi horizon. The top of the board represents the ground surface, and the grid is 3 inches.

QUERCUS ILICIFOLIA (SCRUB OAK)

Scrub oak is very abundant in some upland communities, and scattered individuals are found in the pine 

transition community. The aerial stems come from the 

thickened, often irregular, upper portion of the taproot 

that usually is 2-4 inches thick but may be as thick as 

7 inches. Five main patterns of roots are found: (1) 

one main taproot that extends downward 20-36 inches 

having lateral roots only near the surface of the ground; 

the main taproot branches at the bottom to form an 

extensive network of roots; (2) one main taproot, as 

described above, that also has several well-developed 

horizontal or oblique laterals along its whole length 

(fig. 4); (3) one main taproot that extends obliquely; 

(4) two or more main roots that grow vertically or 

obliquely; and (5) one taproot that forks within a few 

inches of the surface; then the twro branches extend 

horizontally at a depth of 4-8 inches. Figure 5 shows 

these five types of root systems. Types 1, 2, and 4 are 

most common, and types 3 and 5 are rare.

The roots of the scrub oak do not grow into the water 

table even in areas where the water is within 1 or 2 

feet of the surface. The plant occasionally grows in

such areas, but the root system is always very shallow 

(type 5, fig. 5).

FIGURE 4. Taproot of Quercus ilidfolia (type 2, fig. 5). 

QTJERCUS MARILANDICA (BLACKJACK OAK)

Blackjack oak generally attains tree size, but in frequently burned areas it sometimes grows in the same 

shrubby form as scrub oak. Only the roots of the 

shrubby forms were studied. The upper part of the 

taproot is similar to scrub oak, but a large vertical taproot, similar to type 2 described for Quercus ilidfolia 

(fig. 5), is always present and has short or well-developed laterals at various levels.

QUERCUS PRINOIDES (DWARF CHESTNUT OAK)

Dw^arf chestnut oak is common in the upland or the 

extreme upland side of the pine transition community. 

The upper part of the taproot resembles that of the other 

oaks and there are two general patterns of roots: (1) 

a taproot that extends vertically as deep as 4 feet and 

has well-developed laterals and (2) a very extensive
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C7

FIGURE 5. The different types of root systems of Quercus 

ilicifolia.

main root that extends obliquely, similar to type 3 described for Quercus ilicifolia (fig. 5). One plant examined had a root that extended obliquely 10 feet, at 

which distance it was about 2 feet deep, and then 

branched, the longest branch being more than 7 feet long. 

One or more roots of Q. prinoides commonly extend to 

the water table if it is within 3-4 feet of the surface.

GAULTHERIA PROCUMBENS (TEABERRY)

The very small teaberry shrub is abundant both in the 

pine transition community and the upland communities 

that have an A0 soil horizon. Many single aerial stems 

are connected to a rather straight but occasionally 

branched rhizome. The distance between aerial stems 

is 5-12 inches, and the diameter of the rhizome is about 

%6 inch. The rhizome is entirely in the A0 horizon 

or partly in this horizon and partly in the top inch of

the A! horizon. Small finely divided fibrous roots are 

scattered along the rhizome, and generally one small 

root originates at the base of each aerial stem.

TRANSITION ZONE SHBTJBS

KALMIA ANGUSTIFOLIA (SHEEP LAUREL)

Sheep laurel is very abundant in the pine transition 

community and is common in the parts of the upland 

communities adjoining the pine transition community.- 

Many aerial stems are connected by a much-branched 

brittle rhizome. The aerial stems arise singly or in 

groups and may be several inches to 2 feet apart on the 

rhizome. The rhizome can be as much as % inch in 

diameter and is very irregular in direction and pattern, frequently doubling back and crossing over itself. 

The rhizome may be partly or completely in the thick 

A0 horizon in the pine transition community where 

this shrub is so abundant. Short fibrous roots are 

scattered along the rhizome, and dense clusters of fibrous roots occur at the bases of the aerial stems and 

on the rhizome within a few inches of the stems. These 

fine roots become enmeshed with each other and with 

the organic matter of the AO and the top part of the 

A! horizon. This intermeshing, together with the 

complex, brittle rhizome system, forms a very firm sod 

which makes it impossible to excavate and remove much 

of the rhizome system intact. Inasmuch as part of the 

rhizome grows in the A0 horizon, fires in the past may 

have severed parts of a rhizome and isolated groups 

of aerial stems. All these factors make it difficult to 

determine the number of aerial stems connected by a 

common rhizome and to establish whether a complex 

stand is actually only one clone.

Many of these shrubs have roots that originate near 

the base of an aerial stem and extend to or below the 

water table. The water table in the pine transition 

community fluctuates throughout the year, but during 

the summer it is about 18 inches below the land surface 

at the side nearest the cedar swamp and 36-40 inches 

below the surface on the upland side. The root shown 

in figure 6 extended more than 13 inches below the 

water table, and the roots in the water table were very 

lightweight and corky after drying, evidently containing much aerenchyma.

In the past, blocks of sod held together by the roots 

and rhizomes of sheep laurel were cut and used by charcoalers to cover stacks of wood to exclude air during 

the charcoaling process. Similar blocks of sod were 

used in making cranberry-bog dams. These practices 

left circular turf balds which are still quite distinct and 

free of shrubs although the charcoal industry became inactive 75-100 years ago (McCormick, 1955).
C8 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

FIGURE 6. Root of Kalmia angustifolia that extended 40 inches 

below the soil surface and 13 inches below the water table.

CLETHRA ALNIFOLIA (SWEET PEPPERBUSH)

Sweet pepperbush is abundant in the hardwood 

swamp, common in the cedar swamp and pine transition 

communities, and rare throughout the upland. Aerial 

stems arise singly or in pairs from a branching rhizome 

system and may be as close together as 3-4 inches or as 

far apart as 8 feet. In areas where the A0 horizon is 

very thin or absent, the rhizome is in the top 2 inches of 

the Aj horizon, but where a thick A0 horizon is present 

the^ rhizome may be partly or completely in this layer. 

The diameter of the rhizome ranges from % to % inch. 

Small short roots are scattered along the rhizome and 

clustered at the base of the aerial stems. Longer roots 

may arise on the rhizome near the base of an aerial 

stem. These roots generally extend horizontally, but 

they may extend to the water table in the pine transition community (fig. 7).

FIGURE 7. Part of a rhizome of Clethra alnifolia having a root 

that extended 22 inches into the soil.

LYONIA MARIANA (STAGGERBUSH)

Staggerbush is common in the pine transition community and the lower edges of the upland communities 

bordering it. Aerial stems arise singly or in groups 

from an extensive rhizome system in the AX horizon. 

A few small, short roots are scattered along the rhizome 

or clustered at the bases of the aerial stems. The shrub 

often forms small clones having a few to many aerial 

stems connected to a central rootstock. One well-developed clone (fig. 8) had several roots that originated 

from the thick rootstock and extended 40 inches to the 

water table. Groups of aerial stems connected by a 

rhizome, but not in such a compact clone, also usually 

have a deep root that departs from a thickened area on 

the rhizome. One small clone of Lyonia mariana had 

the deepest penetrating root of any of the shrubs studied. This root extended 58 inches to the water table

FIGURE 8. Top view of a clone of Lyonia mariana,. This clone 

had several roots that extended 40 inches to the water table.
DISTRIBUTION OP ROOTS AND RHIZOMES IN SOIL TYPES

where it was broken during excavation (fig. 9). These 

deeper roots generally are sparsely branched near the 

surface but may have many branched and rebranched 

laterals at lower depths.

' c \ ,^r

- * " ->**~<| ^J^ W P -»!

v--^ 1 *^U ^L' " *** * '^1 's,R* ?r- *','> # r. <i"d* ^ *-

,> ' ».: v- Jm~ ->SBtoi?* «.-% *

f u!v^ 4 ^ !;*>""

*M> sr A- \. >^

x«K

^ , n *" '* '- 

.**>';'< .

 «..f;^?"

*. <

FIGURE 9. Root of Lyonia mariana, that extended 58 inches to 

the water table where the root was broken during excavation.

The rhizomes of all the other species studied are 

smooth, but those of Lyonia mariana have small, 

spirally arranged woody projections along their entire 

length. Examination of transverse sections of the 

rhizome revealed that these projections are broad parenchyma rays that are continuous with the pith. They 

probably originated as auxiliary buds and were continued by the cambium as the rhizome increased in 

diameter.

GAYLTISSACIA FRONDOSA (DANGLEBERRY)

Dangleberry is abundant in the cedar swamp, hardwood swamp, pine lowland, and pine transition communities and is common but scattered in the upland

communities. Two or more aerial stems arise from 

an extensive branched rhizome system. The stems may 

be closely spaced on the rhizome, but they usually are 

2-6 feet apart. The rhizome ranges from % to % inch 

in diameter and may be entirely in the A0 horizon or 

partly in this horizon and partly in the top 2 inches of 

the AX horizon. The rhizome may be completely devoid 

of small roots or it may have a few small short roots 

scattered or in patches on the rhizome. On some shrubs 

a root as much as 48 inches long originates near the base 

of an aerial stem or near the fork of a rhizome, but 

generally the roots are less than 9 inches long. All 

roots occur in the same level as the rhizome.

MYRICA PENSYLVANICA (BAYBERRY)

Bayberry is rare and is found mainly in the pine 

transition community, but some isolated plants are 

found in upland areas. One or more aerial stems arise 

from a rhizome which is %6~% inch in diameter. The 

shrub usually occurs where an A0 horizon has formed, 

and the rhizomes may be completely in it or partly in 

it and partly in the top half inch of the AI horizon. 

A few short roots grow along the rhizome, and longer 

roots, as much as 12 inches in length, are occasionally 

found. Some roots extend as deep as 20 inches in the 

pine transition community and as deep as 24-30 inches 

in the upland communities. A nodular swelling was 

found on one root system.

ILEX GLABRA (INKBERRY)

Inkberry is rare to common in all the lowland communities and in the pine transition community but is 

very rare in the upland communities. Several aerial 

stems arise singly or in groups from a rhizome that 

ranges in diameter from %6 to y2 inch. The rhizome 

grows in the A0 horizon or the upper 2 inches of the 

AX horizon. A few small fibrous or woody roots occur 

along the entire rhizome. Larger roots, as much as 

48 inches long, occur at infrequent intervals and may 

extend to the water table if it is near the surface.

HOOTS AND KHIZOMES OF LESS COMMON SHRUBS 

KALMIA LATIFOI/IA (MOTJNTAIN-LATJREiL)

Clumps of mountains-laurel are scattered throughout 

the cedar swamp, pine transition, and upland communities. Many aerial stems come from an irregularly 

shaped knobby solid rootstock 10 inches or more in its 

largest dimension and several inches thick (fig. 10), and 

many small fibrous roots occur at the base of each aerial 

stem. Larger roots grow from the sides and bottom of 

the rootstock and extend either vertically or obliquely 

downward from a few inches to more than 30 inches 

deep. The size of the roots at the junction with the
CIO HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

rootstock ranges from y16 to 2 inches, but the roots are 

extremely brittle and it is almost impossible to trace 

them to their end. In very old plants the central 

rootstock may be rotted apart and separated into various 

groups of aerial stems connected to one or more roots. 

This species is probably less abundant in the area now 

than in the past because plants have been removed for 

ornamentals and the rootstocks have been dug to make 

tobacco pipes (McCormick, 1955).

FIGUEE 10. Rootstock and larger roots of Kalmia laUfolia.

HUDSONIA ERICOIDES (GOLDEN HEATHER) AND LEIOFHYLLTJM BUXIFOLITJM (SAND MYRTLE)

Hudsonia, ericoides is a small shrub which is rare in 

most of the upland communities but is abundant along 

roads and in clearings. Leiophylluon ~buxifolium is a 

small prostrate shrub that occurs mainly in the pine 

transition community. The low bushy aerial parts of 

these plants arise from a single group of roots. One 

small woody root commonly extends about 6 inches deep, 

and a group of fibrous roots originates just below 

ground level and extends obliquely downward 1-4: inches 

(fig. 11). The only evidence of a root graft in the 

species studied was found in H. ericoides. Two

FIGUBE 11. Diagram of root system of Hudsonia ericoides and 

Leiophyllum ~buxifolium.

branches of a woody root of one plant had grown 

around and apparently fused with the woody root of 

another plant.

Harshberger (1916) stated that both these species had 

rhizomes; however, numerous plants of both species 

were excavated and no evidence of a rhizome was found.

Maleberry is common in the hardwood swamp, pine 

transition, and pine lowland communities but very rare 

in the upland communities. The description given for 

the root and rhizome system of Gaylussacia frondosa 

(p. C9) applies to this species except that the aerial 

stems of Lyonia ligustrina may be as much as 13 feet 

apart on the rhizome (fig. 12).

FIGURE 12. Part of a very extensive system of Lyonia ligustrina. The grid on the board is 6 inches.

COMPTONIA PEREGRINA VAR. ASPLEINIFOLIA (SWEET

FERN)

Sweet fern is rare in the upland communities, the pine 

transition community, and the pine lowland community 

but is common in disturbed areas such as gravel pits. 

An irregularly branched rhizome, %-% inch in diameter, gives rise to one or more aerial stems that are 

usually 2-12 inches apart. The rhizome generally occurs in the upper 2 inches of the Ax horizon. A few 

small short sparsely branched roots are scattered along 

the rhizome, and a few longer roots may extend as deep 

as 10 inches.

VACCINIUM ANGUSTIFOLITJM (LOW SWEET 

BLT7EBERRY)

Low sweet blueberry does not grow in most areas on 

the watersheds in the Lebanon State Forest, but it may 

occur in some upland communities and in the pine lowland community. Two or more aerial stems arise from 

a thin rhizome %-%6 inc^ m diameter. The rhizome
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES Gil

grows both in the A0 horizon and the top inch of the 

A! horizon. Small short fibrous or woody roots as 

much as 6 inches long are scattered along the rhizome 

and grouped at the bases of aerial stems or near a fork 

in the rhizome. A few roots as much as 3 feet long 

and extending 3-5 inches deep are fairly common.

Hall (1957) found a distinct taproot in Vaccinium 

angustifolium var. laevifolium in Canada. In the Pine 

Barrens this type of deep-growing root was found in V. 

vaciUans but not in V. angustifolium.

AMELANCHIER CANA»ENSIS (SERVICEBERRY) AND 

PYRTJS MELANOCARPA (BLACK CHOKEBERRY)

Serviceberry and black chokeberry are rare, occurring 

mainly in the lowland communities or in the pine transition community. One to several aerial stems arise 

from a branching rhizome system in the A0 horizon and 

the upper inch of the AI horizon. The rhizomes range 

from %6 to % inch in diameter in Amelaxncfiier canadensis and are as much as 14 inch in diameter in Pyrus 

melanocarpa. A few small short fibrous or woody 

roots are scattered along the rhizome, and occasionally 

a longer root, as much as 15 inches long, arises near the 

fork in a rhizome and extends 3-4 inches deep.

UNDERGROUND RHIZOME GROWING TIPS

Underground rhizome growing tips are the nonwoody 

terminal parts of actively growing rhizomes. They 

were found 011 at least some plants of all the rhizomatous species studied. Eoot tips were not studied. The 

rhizome growing tips are usually white or yellowishwhite and range from 1 to 4 inches in length and from 

Vie to ys inch in diameter at the base. Spirally arranged scale leaves, which are the same color as the tip, 

are always present. The leader of the rhizome that 

terminates in the growing tip is the same diameter as 

the base of the tip and generally does not taper much 

between the junction with the rest of the rhizome and 

the base of the growing tip. The leader may be a few 

inches to several feet long and usually is lighter in color 

than the rest of the rhizome, especially near the growing 

tip. Scale leaves similar to the ones on the rhizome 

growing tip occur on the leader near the tip, but these 

leaves become less and less distinguishable as the distance from the tip increases.

One or two rhizome growing tips commonly occur on 

a rhizome branch that has previously terminated in an 

aerial stem. They arise from axillary buds just back 

of the point where the rhizome turns upward and in 

some species these tips may arise and grow entirely in 

the A0 horizon. Trevett (1956) described in detail the 

process of rhizome elongation and origin of new aerial 

stems of Vaccinium angustifolium and related species.

Some rhizome growing tips turn upward and give rise

225-469 O 66 3

to new stems. Numerous rhizome growing tips may 

arise from the same region of a rhizome but of these 

tips only one or two appear to be vigorous and evidently 

dominate the others. The underground rhizome growing tips of Comptonia peregrina var. asplenifolia., Gaultheria procumbens, and Myrica pensylvanica have the 

same aroma when crushed as the leaves, but the woody 

parts of the rhizomes have no aroma.

Underground growing tips commonly found in Kalmia angustifolia suggest that this shrub is capable of 

extending vegetatively into areas unoccupied by vegetation. However, K. angustifolia has not reinvaded 

the turf bald areas, which remain almost free of any 

shrubs. The reason for the absence of vegetation in 

these areas are not known.

SEEDLINGS

All small shrubs that appeared to be seedlings were 

carefully excavated. However, almost all small shrubs 

of the rhizomatous species were simply new aerial stems 

from a rhizome. One seedling of Lyonia mariana and 

one seedling of CletJira alnifolia were the only ones of 

rhizomatous species found. Numerous seedlings of 

Qercus ilicifolia were found in many areas and many 

were still attached to the acorn. Many small Hudsonia 

ericoides plants were found which presumably were of 

seedling origin. The ecological significance of the lack 

of seedling reproduction of most shrub species in the 

Pine Barrens is not known. Additional research is 

needed to determine if these species produce viable seed 

and, if they do, to determine why seedlings do not become established, particularly in areas made shrubless 

by burning or bare by removal of shrubs.

RELATION OF ROOT DISTRIBUTION TO DIFFERENT 

SOIL TYPES

SOIL PROFILES

The slopes and lowlands of the experimental watersheds are veneered with deposits of pale-yellow-orange 

sand, primarily remnants of the underlying Cohansey 

Sand, mixed with gravel from the Bridgeton-Pensauken 

complex which caps the tops of most of the divides. A 

small amount of Beacon Hill Gravel is present at the 

eastern end of McDonalds Branch watershed (Bacho, 

1955). Most of the soils of the watersheds are derived 

from the Cohansey Sand, but the Downer sand (proposed name), leached phase, and the Lakeland sand, 

leached A2 phase, which occupy the higher divides, are 

mainly derived from the Bridgeton-Pensauken complex 

(Markley, 1955).

In this report, soil profiles are described as they were 

observed in one soil pit for each soil type with the exception of the Lakewood and Leon sands. Descriptions of
012 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

the soil horizons are based on field observations and are 

similar to those reported by Markley (1955). Terminology follows the U.S. Department of Agriculture Soil 

Survey Manual (1951). The percentage of each watershed covered by the various soil types was given by 

Markley (1955).

Certain characteristics are common to most of the 

soils, namely, a single grain structure, an abrupt boundary between horizons (transition zone less than 1 in.), 

and a smooth (nearly plane) topography of the boundaries between soil horizons. Descriptions of colors 

are quite general and are based on dry-field conditions. 

In most of the well-drained soils the B2 horizon grades 

gradually into the C horizon, and the boundary is so 

diffused that there is no definite demarcation.

Four soil types to which Markley (1955) assigned 

only numbers in the original description are given names 

in this paper. The Lakewood sand, clay substratum 

variant, was originally referred to by Markley (1955) 

as soil type 9A16; the Downer sand (proposed name), 

leached phase, was referred to as soil type 9E16; the 

Lakeland sand, leached A2 phase, was referred to as 

soil type 9Y16; and the Lakehurst sand, thick A2 variant, was referred to as soil type 9526.

The Lakewood sand pine-shrub and Lakewood sand 

pine-shrubless sites are located on McDonalds Branch 

watershed, and the site in the Lakewood sand, clay 

substratum variant, is near an old clay pit just outside 

the watershed boundary near the McDonalds Branch 

gaging station. All other sites are on Middle Branch 

watershed.

Where it could be determined, the depth to the water 

table is included in the description of the soil profiles. 

Where no depth is indicated, the water table is well 

below the bottom of the soil pit (4 ft deep).

Because of the scanty spring and summer rainfall 

in 1957, the depth to the water table in some of the soils 

may be below average. The 1957 precipitation records 

from the network of rain gages in the Lebanon State 

Forest show only about 12.9 inches of rain from April 

through September, but the 1948-57 average of a nearby 

station for this period was 22.1 inches (E. C. Rhodehamel, written commun., 1958). Furthermore, in October 1957, water levels in shallow observation wells in 

Lebanon State Forest were 1-2 ieet below the October 

1956 levels (E. C. Rhodehamel, written commun., 1958).

Results of the mechanical analyses and permeability 

measurements for each horizon of the various soil types 

are given in table 1. Separate percentages of silt and 

clay are not reported for most horizons, and the combined clay-silt percentages appear to be unusually low 

for most of the soils. More than half of all horizons 

contain from 97 to 99.9 percent sand. Samples of Lakewood sand on the controlled-burned plots on the western 

end of Middle Branch watershed were analyzed by the 

Soils Department of Rutgers University. These samples contained 1.0-12.9 percent clay, 2.2-15.4 percent 

silt, and 73.0-96.6 percent sand (S. J. Toth, written 

commun., 1958). Although the soils are not necessarily 

comparable, the values for the Lakewood sand from the 

burned plots are consistently higher in silt and clay and 

lower in sand than the values shown in table 1 for the 

other soil samples.

The names of the plant communities at each site are 

based on the vegetation map prepared by McCormick 

(1955). The presence and abundance of the trees and 

shrubs immediately surrounding the soil pit is given 

in table 2.

LAKEWOOD SAND 9706

The well to excessively drained Lakewood sand, 

formed on coarse unconsolidated siliceous sand, is highly 

leached, rather acid, and has a low moisture-holding 

capacity and low nutrient status (Tedrow, 1952). It 

is the most common soil type on the watersheds, covering 25 percent of Middle Branch watershed and 45 percent of McDonalds Branch watershed. At the site studied the AGO horizon was 1 inch thick and the A0 horizon 

was % inch thick. The At horizon extended from 0 to 

2% inches and was black to dark gray. The light-gray 

A2 horizon extended from 2% inches to 121/2 inches. 

The irregular Bj horizon had a strong-brown color and 

a very weak blocklike structure, and ranged in thickness 

from 0 to iy2 inches, the average being about 14 inch. 

Extending downward from about 13 inches, the B2 horizon was strong yellow at the top and with depth graded 

to darker yellow or yellow brown and showed no evidence of mottling. All horizons contained slightly more 

than 97.0 percent sand (table 1). An extremely small 

amount of gravel was present in all the horizons, but 

this soil type often contains much more gravel 

(Markley, 1955). The permeability ranged from 8.0 

inches per hour in the Bt horizon to 22.0 inches per hour 

in the B2 horizon (table 1). The site chosen for study 

was in a chestnut-oak community, and the abundance 

of the trees and shrubs immediately surrounding the 

soil pit is given in table 2.

LAKEWOOD SAND, CLAY SUBSTRATUM VARIANT 9A16

The well-drained Lakewood sand, clay substratum 

variant, is developed from a sandy material underlain 

by a clay stratum which in turn is underlain by other 

sand beds (Markley, 1955). It is found only in one 

small area, covering less than 1 percent of the watershed, 

on the eastern end of McDonalds Branch watershed.

At the site studied, the A00 horizon ranged from V2 

to 1 inch in thickness; the A0 horizon had the same
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C13

TABLE 1. Mechanical analysis and permeability data of the soils studied

Soil

Lakewood sand (pine-shrub 

and pine-shrubless site).

Lakewood sand, clay substratum.

Downer sand, leached phase ...

Lakeland sand, leached A: 

phase.

Lakehurst sand, thick As 

variant.

Horizon

Ai.__ ...

Aj... 

Bi-

.... .

Bs ... -

Ai.. 

Ai.... 

Bi_.._ 

B2 ... -

Ai.... 

Aj.-... 

Bi ». _.. 

Bj»._. ...

Du. . .......

DIA,.. 

Ai... 

Bji . 

Bi» 

Di.. 

Ai.... 

Aj.... 

Bu 

Bi..... .

Ai...... 

Aj.... 

Bi-

 

Bs 

Ai... 

A2. 

Bu... 

Bj.... 

Ai 

AsBi. 

Bj....... ....

Ai

Aj ...

Bu. 

Bi. 

Analysis, in percent of 

Clay Silt

2.6 

2.0 

3.0

.8

4.7 

.1 

2.9 

2.4

6.1 

8.8 

10.0 

18.5 

66.6 | 28.8 

9.0

4.4 

3.8 

3.2 

6.7 

9.1

9.3 

4.3 

4.0 

3.8

2.7 

2.6 

2.9 

2.5

2.5 

.7 

2.3 

2.7

2.0 

2.4 

4.7 

1.7

2.5 

1.4 

1.3 

1.0

Total sand

97.4 

98.0 

97.0 

99.2

95.3 

99.9 

97.1 

97.6

93.9 

91.2 

90.0 

81.5 

4.6 

91.0

95.6 

96.2 

96.8 

93.3 

90.9

90.7 

95.7 

96.0 

96.2

97.3 

97.4 

97.1 

97.5

97.5 

99.3 

97.7 

97.3

98.0 

97.6 

95.3 

98.3

97.5 

98.6 

98.7 

99.0

Very fine 

sand

4.8 

5.8 

5.9 

3.3

3.2 

1.3 

3.2 

2.1

4.3 

4.5 

4.2 

5.0 

.4 

1.7

4.9 

5.3 

4.1 

4.4 

5.4

3.4 

5.4 

3.5 

6.0

5.3 

7.0 

5.4 

5.4

.3 

1.1 

1.7

.8

4.1 

5.7 

5.5 

3.2

1.9 

3.1 

.6 

.3

Fine sand

30.4 

32.1 

32.8 

28.7

15.5 

11.0 

15.4 

14.7

19.6 

19.2 

17.0 

17.3 

.2 

8.5

23.9 

24.4 

24.4 

14.5 

18.6

21.0 

25.9 

19.6 

30.3

30.2 

33.9 

30.2 

32.1

7.6 

15.4 

17.6 

19.8

15.0 

35.2 

31.7 

28.5

17.0 

20.6 

17.2 

10.3

Medium 

sand

44.6 

43.2 

41.3 

47.1

51.3 

49.8 

52.0 

52.1

38.6 

35.3 

32.9 

28.4 

1.6 

49.7

43.5 

42.2 

45.5 

20.5 

26.7

38.0 

37.7 

35.6 

40.0

47.5 

43.4 

46.2 

45.2

43.4 

48.1 

46.4 

47.4

60.9 

44.5 

42.4 

44.7

49.7 

43.7 

51.5 

47.9

Coarse 

sand

16.4 

15.3 

15.1 

18.6

21.4 

30.5 

22.0 

20.8

24.3 

23.1 

24.4 

21.8 

1.4 

25.2

19.1 

19.3 

18.0 

21.9 

22.4

23.7 

21.0 

26.7 

15.8

13.6 

12.2 

14.1 

13.7

39.9 

29.4 

25.9 

25.0

16.9 

11.1 

13.2 

16.9

27.3 

25.7 

23.9 

33.0

Very 

coarse sand

1.2 

1.6 

1.9 

1.5

3.9 

7.3 

4.5 

7.9

7.1 

9.1 

11.5 

9.0 

1.0 

5.9

4.2 

5.0 

4.8 

32.0 

17.8

4.6 

5.7 

10.6 

4.1

.7 

.9 

1.2 

1.1

6.3 

5.3 

6.1 

4.3

1.1 

1.1

2.5 

5.0

1.6

5.5 

5.5 

7.5

All gravel

0.1 

.1 

.1 

.1

.6 

1.3 

2.0 

9.6

5.4 

11.8 

19.1 

38.0 

0 

.5

.4 

.3 

3.1 

70.3 

16.7

.3 

.6 

2.1 

2.4

0 

.2 

0 

.1

.5 

4.0 

9.0 

10.5

0 

0 

.5 

1.6

.2 

1.1 

1.0 

4.4

Permeaability 

(in. per 

hour)

10.0 

15.4 

8.0 

22.0

15.4 

20.0 

20.7 

53.4

12.0 

24.0

10.7 

.002

46.8 

42.8 

42.8 

41.4 

8.0

8.0 

7.3 

8.0 

10.7

12.0 

6.0 

12.0 

17.4

24.0 

28.1 

12.0 

18.0

23.4 

17.4 

4.5 

36.4

16.8 

30.7 

4.0 

34.8

1 Top of sample-. 

zBottoir of sample.

TABLE 2. Presence and abundance of trees and shrubs immediately surrounding the soil pit

in each soil type

[VA, very abundant; A, abundant; C, common; S, scarce; R, rare; 0, absent]

Plant

Trees:

Q. stettata.. 

Q.aZtot 

Shrubs:

Q.ilkifolia.-. .......... ...............

Comptonia peregrina var. asplenifolia. ....

Well drained soils

1

C 

C 

0 

A 

0 

0 

0 

0

A

C 

S 

0 

0 

0 

0

c

0 

0 

0

2

A 

C 

0 

0 

S 

0 

0 

0

A 

A

C

c

s

0

s 

c

0

s

R

3

A

S

s

0

s 

s

R 

0

A 

A

S 

C 

0 

0 

0 

0 

0 

0 

0

4

C 

C 

0 

A 

0

s

0 

0

c

A

A 

S 

0 

0 

0 

0 

0 

0 

0

5

A

0 

S 

0 

0 

0 

0 

0

A 

A

0 

0 

0 

0 

0 

0 

0 

0 

0

6

A

0

s

0 

0 

0 

0 

0

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0

Imperfectly 

drained soils

7

C 

C 

0 

A 

0 

0 

0 

0

A 

A

A

S 

0

s

0 

0 

0 

0 

0

8

C 

0

s

0 

0 

0 

0 

0

A

A 

C 

S 

R 

C 

0 

0 

0 

0 

0

Poorly 

drained soils

9

A

0 

0 

0 

0 

0 

0 

R

0 

0 

A 

0 

VA 

C 

S 

0

c

0 

0

10

c

0 

0 

0 

0 

0 

0 

0

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0

1. Lakewood sand (oak site).

2. Lakewood sand, clay substratum variant.

3. Downer sand, leached phase.

4. Lakeland sand, leached A2 variant.

5. Lakewood sand (pine-shrub site).

6. Lakewood sand (pine-shrubless site).

7. Lakehurst sand.

8. Lakehurst sand, thick Aa variant.

9. Leon sand.

10. Leon sand (turf bald site).
C14 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

range, the average being % inch. The AI horizon was 

black to very dark gray and extended from 0 to 2 inches, 

and the gray A2 horizon extended from 2 to 8 inches. 

The Bx soil horizon was not distinguishable. The B2 

horizon was distinguished from the A2 horizon primarily by its strong-yellow color, and the horizon extended from 8 to 18 inches. A zone of sand, silt, clay, 

gravel, and irregular development of ironstone concretions marked the unconformity between the bottom of 

the B2 horizon and the top of the clay layer (Dx horizon) . The light-yellow DI horizon contained 66.6 percent clay, 28.8 percent silt, and 4.6 percent sand (table 

1), had a blocky or columnarlike structure, and extended 

from 18 to 42 inches. The clay layer is a feature of 

deposition, and the upper horizons of the profile did not 

develop from this material. An irregular formation of 

ironstone concretions was found at the boundary between the bottom of the clay layer and the top of the 

strong-yellow sandy layer (D2 horizon). The At, A2, 

top part of the B2 , and D2 horizons contained 90.0 percent sand or more, and the bottom of the B2 horizon 

contained 18.5 percent clay and silt and 81.5 percent 

sand (table 1).

The site studied was in a pine, black oak, and scrub 

oak community; the vegetation immediately surrounding the soil pit is listed in table 2. Several of the shrubs 

at this site Lyonia mariana, Kalmia angustifolia, and 

Ilex glabra are usually confined to areas where their 

roots can extend to the water table and very seldom 

occur in any abundance on upland sites. During the 

growing season in the New Jersey Pine Barrens, an 

average of 8-11 days per month have 0.01 inch or more 

precipitation (Martin and Corbin, undated). The relatively impervious clay stratum of this soil (permeability of 0.002 in. per hr as compared with 24.0 in. per hr 

in the A2 horizon; see table 1) probably retards the percolation of water from these frequent rains and may 

improve the water conditions above the clay layer 

enough to make conditions favorable for these shrubs.

DOWNER SAND, LEACHED PHASE 9E16

The well-drained Downer sand, leached phase, differs 

from the Lakewood sand in that it has a sandy-loam or 

a loamy-sand subsoil and a rather thin A2 horizon. It 

covers 10 percent of the area of both watersheds. At 

the site studied the A00 horizon was i/£-l inch thick, 

and the A0 horizon ranged from y2 to V/2 inches in 

thickness, the average being % inch. The Ax horizon 

was black to very dark gray and extended from 0 to 2% 

inches, and the gray A2 horizon extended from 2^ to 7 

inches. No Bx horizon could be distinguished. The 

B2 horizon extended from 7 to 38 inches and was distinguished from the A2 horizon primarily by its strongyellow color. Much gravel mixed with the sand (70.3 

percent by weight; see table 1) was found from 23 inches 

to the bottom of the B2 horizon. Below the B2 horizon, 

the strong-yellow Dx horizon had a slightly blocklike 

structure. The permeability of the Dx horizon (8.0 in. 

per hr) was much lower than the permeability in any 

other horizon (table 1). Markley (1955) found the Dx 

horizon nearer the surface than the horizon encountered 

here; Markley's DI horizon also was underlain by loose 

sand, but a lower sand layer was not present down to 4 

feet at this site. The site chosen for study was in an 

oak-pine community; the trees and shrubs immediately 

surrounding the soil pit are listed in table 2.

LiAKKTiAND SAND, LEACHED A2 PHASE 9Y16

The well-drained Lakeland sand, leached A2 phase, 

has an extremely shallow leached horizon and covers 8 

percent of the area of Middle Branch watershed and 6 

percent of the area of McDonalds Branch watershed. 

At the site studied the A00 horizon ranged in thickness 

from 1 to iy2 inches, and the A0 horizon was 1 inch 

thick. The Ax horizon was black to very dark gray and 

extended from 0 to 2 inches, and the gray A2 horizon 

extended from 2 to 5 inches. The irregular Bx horizon 

had a strong-brown color and a very weak blocklike 

structure; it ranged in thickness from i/2 to 2% inches, 

the average being 1 inch. Extending downward from 

6 inches, the B2 horizon was strong yellow at the top 

and graded to light yellow brown with depth. According to Markley (1955), gravel is more common in Lakeland sand than in Lakewood sand, but little gravel was 

present at this site. All horizons contained more than 

90 percent sand, and permeability values ranged from 

7.3 inches per hour in the A2 horizon to 10.7 inches per 

hour in the B2 horizon (table 1). The site studied was 

in an oak-pine community, and the trees and shrubs immediately surrounding the soil pit are listed in table 2.

LAKEHURST SAND 9726

The Lakehurst sand is well drained at the surface 

but is imperfectly drained in the subsoil. It occurs 

where the water table is within 4-10 feet of the surface, 

and it covers 32 percent of Middle Branch watershed 

and 20 percent of McDonalds Branch watershed 

(Markley, 1955). At the site studied the A00 horizon 

ranged from i/2 to % inch in thickness, and the A0 

horizon was % inch thick. The AI horizon was black 

to very dark gray and was 2% inches deep. The lightgray A2 horizon extended from 2% to 12 inches. The 

discontinuous BI horizon had a dark-brown color and 

very weak blocklike structure; it ranged in thickness 

from 0 to li/4 inches, the average being i/2 inch. Extending downward from 12% inches, the B2 horizon
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C15

was a strong yellow at the top and became light yellow 

with depth. Indistinct mottling was found at 48-50 

inches, and gravel was also present, mixed with sand 

at this depth. All the horizons contained more than 

97 percent sand, and permeability values ranged from 

6.0 inches per hour in the A2 horizon to 17.4 inches per 

hour in the B2 horizon (table 1). The site chosen for 

study was in an oak-pine community; the trees and 

shrubs immediately surrounding the soil pit are listed 

in table 2.

LAKEHURST SAN1>, THICK A2 VARIANT (GRADING 

TOWARD LEON SAND)

The deeply leached Lakehurst sand, thick A2 variant, 

is intermediate between Lakehurst sand and Leon sand 

in natural-drainage characteristics and occupies sites 

where the depth to the water table is usually no more 

than 3 to 4 feet (Markley, 1955). This soil covers 

5 percent of Middle Branch watershed and less than 

1 percent of McDonalds Branch watershed. At the site 

studied the A00 and A0 horizons were less than 14 inch 

thick. The Ax horizon was very dark gray to black 

and extended from 0 to 2y% inches. The A2 horizon 

was light-gray to white sand and extended from 2^ 

to 31 inches. The strong-brown B± horizon had a weak 

blocklike structure and ranged in thickness from 1 to 

7 inches, the average being slightly less than 3 inches. 

The light-yellow B2 horizon extended downward from 

34 inches. At the time of the fieldwork (July, 1957), 

the water table was about 50 inches below the surface, 

but it would have been less during a summer that was 

not so extremely dry. All horizons contained more 

than 97 percent sand (table 1), and some gravel extended downward from 16 inches. Permeability values 

ranged from 12.0 inches per hour in the B± horizon to 

24.0 inches per hour in the At horizon (table 1). The 

site chosen for study was in a pine transition community, and the trees and shrubs immediately surrounding the soil pit are listed in table 2.

LEON SAND 9736

The Leon sand is developed where the water table is 

1-2 feet below the surface during the winter and as 

much as 5 feet below during the summer. It covers 

12 percent of Middle Branch watershed and 2 percent 

of McDonalds Branch watershed (Markley, 1955). At 

the site studied the A00 horizon ranged in thickness 

from 1 to 5 inches, and the A0 horizon was 1 inch thick. 

The A! horizon was black to very dark gray and extended from 0 to 3 inches. The A2 horizon was very 

light gray and extended from 3 to 21 inches. The 

strong-brown B! horizon had a weak blocklike structure 

and ranged from iy2 to 6 inches in thickness, the average

thickness being 3 inches. Extending downward from 

24 inches, the B2 horizon had a strong-yellow color with 

depth. All horizons contained more than 95 percent 

sand, and permeability values ranged from 4.5 inches 

per hour in the Bx horizon to 36.4 inches per hour in 

the B2 horizon (table 1). The site chosen was in a 

pine transition community. Pinus rigida was the only 

tree species present, but roots extended into the pit from 

a red maple (Acer rubrum var. trilobum) about 30 feet 

away in an adjoining hardwood swamp. A dense cover 

of Kalmia angustifolia and other shrubs also were 

present (table 2).

ADDITIONAL SITES: LAKEWOOD SAND 9706

Two other sites in Lakewood sand one supporting 

pine with shrubs and the other pine with no shrubs 

were studied to contrast the distribution of roots in 

the same soil at sites having different types of vegetation. The two sites were about 60 feet apart in a pine 

and blackjack oak community. The Lakewood sand 

pine-shrub site had a good shrub cover of Vacciniuan 

vacillans and Gaylussacia baccata, but the Lakewood 

sand pine-shrubless site had no shrubs within 20 feet 

of the pit (table 2). The pine-shrubless site had a 

scattered cover of Carex pensylvanica, but the fibrous 

roots and rhizomes of this species were not included in 

the study. Several acres in this vicinity have little or 

no shrub cover, a condition which may have been caused 

by Indian activities when this locale was used as a 

semipermanent camp (McCormick, 1955). The root 

distribution at these two sites was compared with the 

distribution at the Lakewood sand oak site (p. C12).

The Lakewood sand pine-shrubless site had no A00 or 

A0 horizons, but these horizons were each about y% inch 

thick at the Lakewood sand pine-shrub site. At both 

sites the A± horizon was black to very dark gray and extended from 0 to 2% inches. The light-gray A2 horizon 

extended from 2% to 14 inches, but irregular tongues 

extended into the Bj and B2 horizons as deep as 25 

inches. The irregular B! horizon was strong brown, 

was slightly blocklike in structure, and ranged from 0 

to 2 inches in thickness, the average thickness being less 

than ~y2 inch. Extending downward from 14i/£ inches, 

the B2 horizon was strong-yellow at the top but 

darkened slightly with depth. Because the two sites 

were so close together, soil samples were taken from the 

Lakewood sand pine-shrubless site only. All horizons 

contained more than 95 percent sand, and some gravel 

was mixed with the sand below 16 inches at both sites 

(table 1). Permeability values ranged from 15.4 inches 

per hour in the A± horizon to 22 inches per hour in the 

B2 horizon (table 1).
C16 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

ADDITIONAL SITE: UEON SAND 9T36

An additionnal Leon sand site in a turf bald in a pine 

transition community was chosen, and the root distribution was compared with the distribution in the Leon sand 

in a pine transition community (p. C15). The tree cover 

at the turf bald site consisted only of -Pinus rigida and 

there were no shrubs (table 2). There was a scattered 

cover of Carex pensyl/vanica, but its root distribution 

was not studied. The A00 and A0 horizons were absent, 

and the At horizon extended from 0 to 2% inches. The 

A2 horizon was thicker than at the other Leon sand site, 

extending from 2i/£ inches to 25 inches. The descriptions and dimensions of the B! and B2 horizons at the 

Leon sand site (see p. C15) apply to this site also. At 

the time of the fieldwork (August 1957), the .water table 

was 36 inches below the surface. All soil horizons contained more than 97 percent sand, and there was a small 

amount of gravel below 30 inches (table 1). The permeability values ranged from 4.0 inches per hour in the

BI horizon to 34.8 inches per hour in the B2 horizon 

(table 1).

DEVELOPMENT OF BOOTS 

NUMBER AND AREA OF HOOTS IN THE PROFILE

The total numbers of roots in the profile of the seven 

soil types having comparable vegetation are shown in 

table 3. An analysis of variance indicated that there 

was a significant difference in numbers of roots among 

the sites studied (table 4). The Lakeland sand; the 

Lakewood sand, clay substratum variant; the Lakehurst 

sand; and the Downer sand have the greatest number of 

roots per square foot in the entire profile. Duncan's 

multiple range test (1955) indicated that the total numbers of roots in these four soils were not significantly 

different at the 5-percent level (table 5). However, the 

total numbers of roots in these soils were significantly 

greater than the numbers in the Lakewood sand (oak 

site) and the Lakehurst sand, thick A2 variant.

TABLE 3. Actual number of roots and number and total cross-sectional area of roots per square foot of vertical profile in each horizon

and in the entire profile

[Area per square foot given in square inches]

Soil type Root unit

Horizon

Ao Ai A2 Bi Top 1 ft of 

Bj

Rest of Bs

Total and 

average, 

entire 

profile

Sites having comparable vegetation

Lakehurst sand ____ _ ...................

Lakehurst sand, thick, As variant-- ... ...

Leon sand... _ _ . _

Area per sqft- _____ ____ . ...

No. per sqft.. _________ _ .....

No. per sqft---- ___________

233

311

1.68

335

399

1.25

356

1.48

614

614

3.11

529

1,058

3.15

592

5.09

585

225

1.48

528

176

1.68

526

189

0.82

439

222

1.94

4.QK

193

1.73

650

243

0.95

723

228

2.02

428

42

0.16

498

100

0.59

360

88

0.91

268

99

0.56

<;ru

53

0.69

962

35

0.07

28

0.24

25

83

0.20

220

234

0.75

66

118

0.53

40

14

0.04

98

34

0.23

534

45

0.28

f 708

\ 69

I 0.33

f 947

) 70

I 0.74

927

77

0.47

792

66

0.30

22

2

0.003

100

9

0.09

291

13

0.04

'1,307

54

0.22

2682

35

0.09

1,096

36

0.15

752

32

0.20

2

1

0.0003

2,096

43

0.23

3,377

69

0.36

3,045

63

0.38

3,564

73

0.40

3,138

65

0.44

1,676

35

0.10

2,035

55

0.48

Sites having different vegetation

Lakewood sand (pine-shrub site) __ .. ....

Lakewood sand (pine-shrubless site)---- ...

Actual No . __ _________ . ...

No. per sqft _ _____________

i Data given are for DI horizon. Data for Dj horizon, below the DI horizon are:

Areaoersaft _________________________ ___ . 0.003

193 

508 

3.14

Data 

Ac 

No 

Ar

438 

183 

1.53

228 

107 

0.29

340 

134 

0.24

430 

44 

0.23

181 

14 

0.16

422 

19 

0.03

27 

117 

0.17

19

53 

0.53

8 

4 

0.005

438 

36 

0.19

305 

25 

0.08

19 

2 

0.01

165 

7 

0.02

112 

5 

0.01

1,691 

35 

0.21

845 

18 

0.09

789 

22 

0.04

for DI horizon below 82: tualNo - . _ -174

eaDersaft- . 0.07
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C17

TABLE 4. Analysis-of-variance computations for determining 

differences between the number of roots per square foot in the 

entire profile among the various soil types

Total 

Sum of 

squares

5,610

4,699

911

Degrees of 

freedom.

27

6

21

Mean 

square

783.2

43.4

Calculation:

^=783.2-^-43.4=18.1.

Needed F (5-percent probability) =2.6.

When the cross-sectional area of roots is considered, 

the relative rank of the various soil types is somewhat 

'different (table 3). The Leon sand, which is fifth in 

the number of roots, has the greatest area of roots per 

square foot in the profile. However, differences among 

the various soil types lack significance at the 5-percent 

level (table 5). The two soils with the smallest root 

area the Lakewood sand (oak site) and the Lakehurst 

sand, thick A2 variant also have the smallest number 

of roots.

TABLE 5. Results of multiple-range test comparing the average number of roots in the entire 

profile and in each horizon and the average area of roots in the entire profile among the seven 

soils having comparable vegetation

[Averages followed by common letters are not significantly different at the 5-percent level, as determined by Duucan's 

multiple-range test (1955); for example, the average number of roots per sq ft in the entire profile of the Lakeland sand, 

leached A2 phase, is not significantly different at the 5-percent level from the average number in the Downer sand]

Soil

Lakeland sand, leached Ai phase. --- 

Lakewood sand, clay substratum.

Lakehurst sand, thick As variant -

Av

Entire profile

73 a 

69 a

63ab

55 b

43 c

35 c

jrage number of

At horizon '

222 

176

193

189

228

225

243

'oots per square

A2 horizon

99 d 

100 d

53 c

88d

42 e

35 c

oot

Total B horizon

52 f 

51 f

45 f

AA f

14

24

3

Average area of 

roots (sq in)

per sq ft entire 

profile

0.40g 

.36 h

d.d. P

.38gh

.48g

.23 hi

.10 i

1 For the Ai horizon, the F test in the analysis of variance was not significant at the 5-percent level, so there is no 

significant difference in number of roots in this horizon among the 7 soils.

The relation of the number of roots to the area of the 

roots in the profiles for all soil types and sites is shown 

in figure 13.

NUMBER AND AREA OF ROOTS IN THE VARIOUS 

HORIZONS

The number and area of roots per square foot in each 

horizon in the various soils studied are given in table 3. 

General relations of root distribution in the various 

horizons are discussed in the following sections.

A0 HORIZON

Where it is present, the A0 horizon contains the highest number of roots per square foot of any horizon. 

This organic layer evidently offers rather good conditions for the development of roots and rhizomes. Various authors have observed a similar concentration of 

roots in organic soil layers in other areas. Waterman 

'(1919) found that the roots of shrub species growing on 

dunes in Michigan were largely confined to the leafmold layer on the surface of the sandy soil or to pockets 

of buried organic matter. Proportionately more roots, 

especially finer ones, often occur in the organic layer of 

podzol soils than in other horizons (Swetloff, 1931), 

and roots from lower horizons occasionally extend upward into this organic layer (Partridge and Veatch,

1932). Partridge and Veatch (1931), Beckenbach and 

Gourley (1933), and Costing and Reed (1952) have reported a larger number of roots of various species concentrated in a humus layer or A0 horizon.

A1 HORIZON

The AI horizon is second only to the A0 horizon in 

number and area of roots per square foot except in 

the Lakeland sand in which the Bj horizon contains 

the second highest number of roots. Where no A0 horizon is present, the A2 horizon contains the highest 

number and area of roots. At all sites, the Aj horizon 

probably is the most uniform with respect to texture 

(table 1), organic matter content, and thickness. The 

lack of statistical significance between the mean number 

of roots per square foot in this horizon among the 

various sites (table 5) is further evidence of this uniformity. Coile (1937) and Scully (1942) found that 

the A! horizon contained the highest number of roots 

per square foot in various forest types. According to 

Specht and Ratson (1957), many heath plants in 

Australia have much of their root systems in the AX 

horizon. Other authors have reported concentration 

of tree roots in the A horizon (Korstian and Coile, 

1938; Partridge and Veatch, 1932; and Hopkins and 

Donahue, 1939).
CIS HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

EXPLANATION

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FIGURE 13. Relation of the number of roots to the area of the roots per square foot in profiles for different soil types.

The percentage of the total number of roots found 

in the A0 and AI horizon ranges from 25 percent in the 

Lakewood sand, clay substratum variant, to 65 percent 

in Leon sand (table 6). The percentages of total root 

area in these horizons vary more than the numbers, 

ranging from 15 percent in the Lakewood sand (pineshrubless site) to 65 percent in the Leon sand. The 

following conditions in the upper part of the soil have 

been proposed to explain this concentration of roots: 

better moisture, nutrient, and aeration conditions 

(Lunt, 1934; Stephenson and Schuster, 1937); higher 

content of fine soil particles and organic matter (Lutz

TABLE 6. Relation of roots in AO and AI horizons to total roots in 

entire profile, in percent

Soil Number of 

roots

Area of 

roots

Sites having comparable vegetation

Lakewood sand (oak site).. ._ ____ . _ ............ 39 

25 

29 

30 

33 

39 

65

45 

34 

18 

31 

28 

i 56 

65

Sites having different vegetation

37 

27 

43

49 

i 15 

141

1 No Ao horizon.

and others, 1937); better structure (Lutz and others, 

1937); and better temperature conditions (Swetloff, 

1931; Woods, 1957).

A2 HORIZON

The number of roots per square foot decreases sharply 

from the AI to the A2 soil horizon. The area of roots 

also decreases in all soils but the Downer sand, but the 

decrease in area is smaller than the decrease in numbers. 

The leached condition and lack of nutrients in the A2 

horizon probably is the main factor in limiting number 

of roots found there. The three soils with thin or 

imperfectly leached A2 horizons the Lakewood sand, 

clay substratum variant; the Lakeland sand; and the 

Downer sand have significantly more roots per square 

foot in this horizon than any of the other soils (table 5). 

The higher number of roots in the poorly developed A2 

horizon probably is one reason why these three soils are 

among the top four in number of roots in the entire

profile.

B, HORIZON

In the Lakehurst sand and all the upland soils, the 

number of roots per square foot in the BX horizon is at 

least double the number in the A2 horizon. This increase of roots in the BI horizon was noted by Tedrow 

(1952), who attributed it to a higher concentration of 

available nutrients there. Minerals, organic matter, 

and clay are leached from the upper horizons and
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C19

accumulate in the Bx horizon. This accumulation results in better root development in the BX than in the 

A2 or B2 horizons, at least in the upland soils. The 

number of roots per square foot in the BX horizon does 

not increase in the imperfectly or poorly drained soils 

studied, except for a small increase in the Leon sand. 

The BI horizon is much thicker and better developed 

in these soils than in the well-drained soils, but it is 

also deeper and very near the water table. Poor 

aeration because of this proximity to water in the soil 

probably causes the poor root development in the BI 

horizons of these soils.

The longer roots of many of the species of shrubs 

studied are not necessarily confined to any one soil horizon. However, these roots may show differences in 

shape or in amount of branching in the BX horizon. 

Roots of shrubs within the thick BX horizon of the Leon 

sand are often twisted and may extend horizontally several inches before entering the top of the B2 soil horizon. 

Some roots begin to branch profusely at the point of 

entry into the B! soil horizon (see the root of Kalmia 

angustifolia, fig. 6). The BI horizon of upland soils is 

not as thick as that of the Leon sand, but it also may 

affect root development. The two horizontal branches 

of the root of Vaccinium vacillans shown in figure 3 

were largely confined to the BI horizon of the Lakewood 

sand.

B2 AND OTHER LOWER HORIZONS

In the upland soil types, the top 1 foot of the B2 

horizon generally contains about as many roots per

square foot as the A2 horizon (table 3). The number 

of roots decreases sharply from the top foot to the remainder of the B2 horizon. For the sites with comparable vegetation, the two soils with the shallowest 

water table the Leon sand and the Lakehurst sand, 

thick A2 variant have the fewest roots in this horizon, 

evidently because of the poor aeration in the B horizon. 

The three soils with the thin A2 horizons are among the 

soils having the most roots in the B horizon.

Progressive downward decreases in the number of 

roots in the B horizon evidently is a characteristic of 

most soils. This phenomenon has been reported by 

Swetloff (1931), Yeager (1935), Coile (1937), Garin 

(1942), and others.

DISTRIBUTION OF ROOTS IN DIFFERENT VEGETATIOX

TYPES

The Lakewood sand pine-shrubless site contains significantly smaller numbers and areas of roots in every 

horizon than the other two Lakewood sand sites (table 

7). The Lakewood sand oak site contains more roots 

in the AI horizon, B horizon, and the entire profile than 

the Lakewood sand pine-shrub site, but the difference in 

the area of roots in the profile and number of roots in 

the A2 horizon is not significant between these sites.

The Leon sand site with a good shrub cover has a significantly greater number and area of roots in the entire 

profile and in every horizon than does the Leon sand 

turf bald site with no shrubs.

TABLE 7. Results of multiple-range test comparing the average number of roots in the entire 

profile and in each horizon and the average area of roots in the entire profile among the 

three Lakewood sand sites supporting different vegetation

[Averages followed by common letters are not significantly different at the 5-percent level, as determined by Duncan's 

multiple-range test (1955); for example, the average number of roots per sq ft in the A2 horizon at the oak site is not 

significantly different at the 5-percent level from the average number at the pine-shrub site]

Lakewood sand site

Oak .

Av«

Entire 

profile *

43

35

18

rage number of i

Ai horizon '

225

183

107

'oots per square

Aj horizon

49 a

H a

14

bot

Total B 

horizon 1

24

17

13

Average area 

of roots

(sq in) per 

sq ft, entire 

profile

0.23 b

.21 b

.09

1 All differences are significant for the entire profile, Ai horizon, and B horizon. 

DISTRIBUTION OF ROOTS IN 6-INCH LA.YERS

The actual numbers of roots in the various 6-inch 

layers show the distribution of roots within thick horizons more clearly than the number of roots per square 

foot in the horizon as a whole. However, the data for 

the 6-inch layers encompassing rather thin horizons, 

such as the AI horizon at most sites, differ only slightly 

from the data for the total horizon. As indicated previously, the A0 horizon contains the highest number of 

roots per square foot, where it is present. The top 6 

inches of the mineral soil contains the next highest number (table 8). A further decrease in the number of 

roots from the top 6-inch layer to the second 6-inch 

layer occurs in all soil types, reflecting the drop in the 

number of roots from the AI to the A2 horizon. The 

smallest decreases from the top 6-inch layer to the sec-
C20 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

ond 6-inch layer occur in the three soils with the very 

thin A2 horizons the Lakewood sand, clay substratum 

variant; the Downer sand; and the Lakeland sand.

Comparisons of the cross-sectional area of roots in each 

6-inch layer show the same relationships as the number 

of roots in these layers and are not presented here.

TABLE 8. Total number of roots and number of roots per square foot in each 6-inch layer of the soil profiles

Soil type

Lakewood sand (oaksite)..- _____

ant.

Downer sand ______________

Lakeland sand, leached Aj phase. - _ --

Lakehurst sand.-. __ - ___ - __ -- __

Lakehurst sand, thick A2 variant.---.-.

Lakewood sand Cpine shrubless site) _ -

Unit

No__ 

No. __ -. _ .- ----- -----------

Ao

horizon

233

QI 1

335

1QQ

356

4Q4.

614

614

529

1,058

CQO

5Q9

193

508

0-6

829

1«>B

830

138

816

136

907

J51

714

119

934

156

930

155

720

120

331

55

88

6-12

182

30

544

91

525

88

511

85

286

49

302

50

223

37

154

26

62

10

177

30

12-18

271

45

386

64

445

74

454

76

413

69

200

33

70

12

228

38

106

18

53

9

6-inch

18-24

269

45

404

67

320

53

346

58

419

70

137

23

91

15

221

37

174

29

8

1

layer

24-30

152

25

404

67

241

40

328

54

310

52

58

10

67

11

106

18

92

15

6

1

30-36

69

12

271

45

123

21

279

47

229

38

31

5

62

10

39

7

46

8

20

3

36-42

68

11

186

31

130

22

89

15

139

23

12

2

23

4

23

4

42-48

23

4

17

3

89

15

36

6

99

17

1

7

1

11

o

DISTRIBUTION OF BOOTS OF DIFFERENT SIZES AND

TYPES

ROOTS OF DIFFERENT SIZES

Roots of the smallest size class (0.01-0.05 inch) make 

up 71-89 percent of all roots in the profile in the various 

soil types. Even though they are fewer in number, roots 

more than 0.05 inch in diameter influence the total area 

of roots more than the smaller roots. For example, the 

high area of roots compared to the number of roots in 

the Leon sand (fig. 13) is due to the large proportion of 

larger roots. The pine transition community in which 

the Leon sand was studied has a very dense cover of 

shrubs whose large roots and rhizomes are very abundant in the A0 and Aa horizons. These larger shrub 

roots and rhizomes in these horizons are responsible for 

the high area of roots in the profile.

Further evidence of the effect of larger roots on area 

is shown in the Lakewood sand pine-shrub site and the 

Lakehurst sand, thick A2 variant, which have an equal 

number of roots (fig. 13). The area of roots in the 

Lakewood sand is double that in the Lakehurst A2 variant because of the high proportion of roots more than 

0.05 inch in diameter in the Lakewood sand.

ROOTS OF DIFFERENT TYPES

All roots more than 0.2 inch in diameter at the two 

shrubless sites Leon sand turf bald and Lakewood sand 

pine-shrubless are pine roots. At the other eight sites 

the number and percentage of shrub, pine, and oak roots 

in the entire profile varies considerably (table 9). However, in seven of the eight sites, more than 80 percent 

of all roots larger than 0.2 inch in diameter in the A0 

and AI horizons are shrub roots and rhizomes. Percentages of pine roots in these horizons range from 4 

to 49. Very few oak roots more than 0.2 inch in diameter are found in the A0 and AL horizons, even at sites 

having a large proportion of oak roots in the entire 

profile.

Table 10 contrasts the combined number of differenttypes of roots more than 0.2 inch in diameter in the five 

soils having oak-pine-shrub vegetation with comparable 

data for the three soils having pine-shrub vegetation. 

The three types of roots are about equally abundant in 

the profile at the oak-pine sites. At the three pine sites, 

shrub roots are relatively more important, making up 

71 percent of the total roots in the profile.

Shrub roots make up 71 percent of the total roots in 

the A0 and AI horizons at the oak-pine sites and 90 percent at the pine sites. The studies of individual root 

systems indicated that the majority of the roots and 

rhizomes of most shrubs are concentrated in the A0 and 

AI horizons. This fact is further demonstrated by the 

very high percentages of all shrub roots and rhizomes 

more than 0.2 inch in diameter found in the A0 and 

A! horizons 98 percent in the oak-pine sites and 86 

percent at the pine sites.

If the totals of the different types of roots less than 

0.2 inch in diameter are proportional to those of more 

than 0.2 inch, any differences in the total numbers at 

any two sites having good shrub cover apparently 

would be due to the number of tree roots. Shrub roots 

are concentrated in the AI horizon, and there is no 

statistically significant difference between the total roots 

in this horizon among any of the sites having a good 

shrub cover (table 5). However, as previously pointed 

out, sites having no shrubs do have significantly fewer
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C21

TABLE 9. Number of shrub, pine, and oak roots more than 0.2 inch in diameter in the A0

horizons and in the entire profile

Soil Unit

A0 AI horizons

Shrub Pine Oak | Total

Entire profile

Shrub | Pine Oak | Total

Sites having comparable vegetation

Lakewood sand, clay substratum variant.

Lakeland sand, leached Aj 

phase.

Lakehurst sand, thick A2 

variant. 

Leon sand. ------ --_---_--_-,

No . 

No 

No .... .......

No. 

No......... .......

No .- ....

No - - .

37 

84 

18 

34 

15 

88 

46 

85 

25 

83 

16 

94 

53 

85

5 

11 

26 

49 

2 

12 

8 

15 

3 

10 

1 

6 

8 

13

2 

5 

9 

17 

0 

0 

0 

0 

2 

7 

0 

0 

11 

2

44 

100 

53 

100 

17 

100 

54 

100 

30 

100 

17 

100 

62 

100

43 

54 

18 

18 

15 

23 

47 

41 

25 

28 

19 

79 

66 

68

18 

22 

32 

32 

32 

49 

32 

28 

23 

25 

4 

17 

22 

23

19 

24 

51 

50 

18 

28 

36 

31 

42 

47 

1 

4 

19 

9

80 

100 

101 

100 

65 

100 

115 

100 

90 

100 

24 

100 

97 

100

Sites having different vegetation

Lakewood sand (pine-shrub 

site). 

Lakewood sand (pine-shrubless site) . 

Leon sand (turf bald site) .....

No

No --__--.

No 

44 

96 

0 

0 

0 

0

2 

4 

2 

100 

1 

100

0 

0 

0 

0 

0 

0

46 

100 

2 

100 

1 

100

47 

72 

0 

0 

0 

0

11 

17 

21 

100 

5 

100

7 

11 

0 

0 

0 

0

65 

100 

21 

100 

5 

100

1 Maple root.

TABLE 10. Average number of shrub, pine, and oak roots more than 0.2 inch in diameter in five 

soil types l having oak-pine vegetation and a good shrub cover and in three soil types 2 having 

only pine and shrub vegetation

Roots

Entire profile: 

Average No---- -.._ _- _ _-.

Ao-Ai horizons:

5 sites with oak-pine vegetation 1

Shrub

30 

33

29 

71

Pine

27 

30

8 

22

Oak

33 

37

3

7

All roots

90 

100

40 

100

3 sites with pine vegetation -

Shrub

44 

1 71 

1 

1 38 

90

Pine

12 

20

4 

9

Other

6 

9

1 

1

All roots

62 

100

42 

100

1 Lakewood sand (oak site), Lakehurst sand, Downer sand, Lakeland sand, and the clay substratum variant of the 

Lakeland sand.

2 Lakehurst sand, thick A2 variant; Leon sand; and Lakewood sand (pine-shrub site).

roots in almost every horizon than similar sites having 

a good shrub cover.

EFFECT OF DECAYING ROOTS IN THE SOIL

One or more small roots growing inside a decaying 

root was commonly observed, especially in the A2 horizon. Most of the smaller roots in the thick A2 horizon 

of the Lakehurst sand, thick A2 variant, are growing 

inside decaying roots or are surrounded by a ring of 

organic matter indicating the presence of another root 

at one time. A large decaying root may have as many 

as 12 small roots growing inside it. Any accumulation 

of decaying organic matter in the mineral soil will have 

many fibrous and small woody roots of all species very 

closely intermingled with the decaying particles, a 

condition much like that found in the A0 horizon. This 

phenomenon was also reported by Swetloff (1931), 

Scully (1942), and others.

EFFECT OF SOIL TEXTURE ON ROOT DISTRIBUTION

There are conflicting ideas about the influence of soil 

texture on root development, but most authorities agree 

that root development is generally poorer, in terms of 

number of roots per unit volume of soil, in sandy soils 

than in soils with a higher content of silt and clay. 

Livingston (1906), Aldrich-Blake (1929), Biigsen and 

Munch (1929), and Garin (1942) found that roots in 

sandy soils are longer but have fewer branches than 

roots in finer soils. This condition would result in 

more roots in a finer soil or horizon than in a sandy 

soil or horizon. Turner (1936) and Lutz, Ely, and 

Little (1937) reported that horizons with higher 

amounts of silt and clay contained more roots than 

horizons with lower amounts. Lutz, Ely, and Little 

(1937) also reported that root development was poor 

or absent in soils containing more than 90 percent sand
C22 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

and that when strata of fine-textured material occur in 

sandy soils the majority of the roots are concentrated 

in these strata.

Haasis (1921, 1923), however, found longer, lessbranched roots in a clay soil than in a rocky loam soil, 

and Anderson and Cheyney (1934) found more roots 

on tree seedlings grown in coarse soils. Hopkins and 

Donahue (1939) stated that there is no correlation 

between the percentage of clay in the soil and root 

distribution. These varying results by different investigators were probably due to differences in textures, 

drainage, or compactness of the soils studied.

In the present study the clay layer (Di horizon) 

which underlies the B2 horizon of the Lakewood sand, 

clay substratum variant, greatly alters the distribution 

of roots. The number of roots per square foot in the 

sandy B2 horizon and in the top 1 foot of the clay layer 

are very nearly equal, and there is a small decrease in 

the number of roots from the top 1 foot to the remainder 

of the clay layer (table 3). There is, however, a very 

sharp decrease in roots in the sandy D2 horizon below 

the DI horizon. This decrease seems to indicate that 

the clay is more favorable for root development than 

the sand above and below it and, consequently, offsets 

the normal downward decrease in the number of roots. 

Smaller roots (approximately as much as 0.1 in. in 

diameter) in the clay layer are found only in cracks 

and are very much flattened. Larger roots in general 

have a normal shape and are present throughout the 

horizon instead of only in cracks. Partridge and 

Veatch (1932) noted that roots in clay soils follow 

cracks, and Stephenson and Schuster (193V) found that 

roots in heavy clay horizons were compressed. Scully 

(1942) stated that roots less than 2 mm in diameter 

followed cracks in a sandy-clay B2 horizon and were 

flattened because of the horizon's resistance to 

penetration.

Gravel in a soil may also affect root distribution. 

The taproot or one Quercus marilandica examined in 

Lakewood sand extended downward about 22 inches to 

the top of a layer of gravel, then turned and grew horizontally about 12 feet along the top of the gravel layer.

RELATION OF ROOT DISTRIBUTION TO THE 

WATER TABLE

Poor aeration in .parts of the soil near the water table 

or in poorly drained soils generally causes poor root 

growth of many species. Partridge and Veatch (1932), 

Oskamp and Batjer (1932), and Diebold (1933) found 

that shallow rooting of apple trees is generally a result 

of a high water table. The same situation was reported 

by Hoffman and Schlubatis (1928) for raspberries. 

Stephenson and Schuster (193V) found that poorly

aerated soils contained few roots in the lowest part of 

the profile. Cooper (1926) related the distribution of 

different types of vegetation on alluvial fans to the 

depth of the water table and to aeration of the soil.

In the soils investigated, those at the three sites having 

the shallowest water tables the Leon sand, the Leon 

sand turf bald, and the Lakehurst sand, thick A2 variant have a rather large percentage of the total number 

of roots concentrated in the A0 and A± horizons (table 

6). The soils at these sites have a much thicker A2 horizon than any of the other soils, and this thick, rather 

sterile horizon together with the shallow water table 

and the resultant poor aeration evidently causes this 

poor root development below the A± horizon. Two of 

these soils the Leon sand turf bald and the Lakehurst 

sand, thick A2 variant are among the lowest in total 

root number and root area in the profile, but the Leon 

sand site has the highest area of roots per square foot 

and the fifth highest number of roots per square foot 

in its profile of all sites studied. The Leon sand site is 

located in a pine transition community which has an extremely dense cover of shrubs, mainly Kalmia angustifolia, whose larger roots and rhizomes are very numerous in the A0 and A! horizon (table 9). Even though 

the lower horizons of the Leon sand are wet and probably poorly aerated, the shallow water table is, at least 

in part, responsible for the extremely dense shrub cover. 

K. angustifolia and some of the other shrubs commonly 

growing in the Leon sand in the pine transition community have larger roots which extend to the water 

table and thus are insured an adequate supply of water. 

The roots that extend to the water table evidently 

are not inhibited by submergence or poor aeration.

The shrubs of the region generally fall into three 

categories in relation to the water table: (1) phreatophytes shrubs whose roots usually extend to the water 

table, (2) facultative phreatophytes shrubs whose 

roots extend to the water table in lowland areas but do 

not reach the water table in upland areas, and (3) noiiphreatophytes shrubs whose roots never extend to the 

water table even where it is shallow (table 11). The 

majority of the nonphreatophytes very seldom grow 

where the water table is shallower than 3^ feet. However, Quercus ilicifolia and Vaccinium vacillans grow 

both in upland areas and in areas where the water table 

is near the surface. The roots of both these species penetrate 36 inches or more in the upland communities but 

grow horizontally within a few inches of the surface in 

areas having a high water table. Apparently the roots 

of these species cannot tolerate the conditions in the 

saturated zone of the water table or in the capillary 

fringe above the water table.
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C23

TABLE 11. Relation of roots of the Pine Barrens shrubs to the 

water table

Phreatophytes:

Kalmia angustifolia 

Lyonia mariana 

Chamaedaphne calyculata 1 

Gaylussacia dumosa 1 

Ilex verticillata a 

Leucothoe racemosa * 

Pyrus arbutifolia 1 

Rhododendron mscosum 1 

Vaccinium corymbosum 1

Facultative phreatophytes: 

Amelanchier canadensis 

Clethra alnifolia 

Gaultheria procumbens 

Gaylussacia baccata 

G. frondosa 

Ilex glabra

Facultative phreatophytes 

Continued

Kalmia latifolia

Lyonia ligustrina

Myricct pensylvanica

Pyrus melanocarpa

Quercus prinoides

Vaccinium angustifolium 

Nonphreatophytes:

Comptonia peregrina 

var. asplenifolia

Hudsonia ericoides

Leiophyllum buxifolium

Quereus ilicifolia

Q. marilandica

Vaccinium vacillans

1 Species limited to lowland areas and not included in the present 

study.

Most of the shrubs listed in table 11 as facultative 

phreatophytes are classified as such 'because they grow 

both in the lowland and upland communities. Their 

roots do not extend to the water table in the upland 

areas, but it must be assumed that even superficial root 

systems of the plants in the lowlands do grow into the 

water table or the capillary fringe most of the year. 

However, Quereus prinoides, listed as a facultative 

phreatophyte, does not occur in the lowland communities. In the pine transition community the roots of 

this species may extend to the water table, but in upland 

areas the water table is too deep for the roots to 

reach it.

Exclusive of the strictly lowland species, which were 

not studied, only two species could be classified as true 

phreatophytes, Kalmia angustifolia and Lyonia mariana. K. angustifolia is the most characteristic shrub 

species of the pine transition community and undoubtedly occurs so abundantly there because its roots 

can extend to the water table, which is 18-40 inches deep 

during the summer (fig. 5). L. mariana also occurs in 

the pine transition community and has one or more roots 

that extend to the water table (fig. 7). Both shrubs 

are found in widely scattered locations in upland communities, but the two shrubs seem to be confined mainly 

to areas having a high water table. In some places in 

the> pine transition community, Clethra alnifolia may 

have a root that extends 24 30 inches to the water table 

(fig. 6). However, this species also grows both in upland areas where the water table is very deep and in 

lowland communities where the water table is very near 

the surface, so it must be classified as a facultative 

phreatophyte rather than a true phreatophyte.

Very little is known about comparative use of water

by different species under field conditions. Sartz (1951) 

stated that plants whose roots extend to the water table 

transpire more than plants whose roots obtain moisture 

from other sources. On this basis, it appears that the 

plants in the cedar swamp and other lowland communities whose roots are in the water table or capillary 

fringe most of the year would be much more important 

in the consumption of ground water than the vegetation 

of the pine transition community where not all roots 

extend to the water table. In addition, the lowland 

areas are much more extensive than the pine transition 

community, at least in the Lebanon State Forest 

(McCormick, 1955); therefore any attempt to control 

the use of water by vegetation probably should be 

concentrated on the lowland areas.

Use of water by vegetation can be reduced in two 

ways: (1) lower the water table beyond the roots of 

the plants (consumptive drain would automatically 

accomplish this), and (2) remove species that are heavy 

users of ground water or replace them with species that 

use less water. Hoover (1944) and Hewlett and Hibbert (1961) found that clear cutting of trees on a watershed in North Carolina significantly increased the 

water yield, and Dunford and Fletcher (1947) found 

that cutting the trees along a stream on the same watershed eliminated diurnal fluctuation of streamflow 

during the growing season. Wilm and Dunford (1948) 

reported that cutting of lodgepole pine increased water 

for streamflow, and Croft (1950) found the same thing 

when streamside aspens were replaced with herbaceous 

species. Veihmeyer (1953) and Fletcher and Rich 

(1954) noted that the replacement of shrubs with 

grasses and forbs resulted in an increased amount of 

water available for streamflow. In North Carolina, a 

rise in the water table resulting from the clear cutting 

of loblolly pine was reported by Trousdell and Hoover 

(1954). The wide scale killing of spruce trees by the 

Englemann spruce beetle resulted in a significantly 

greater streamflow on a watershed in Colorado (Love, 

1955).

If necessary, the shrubs of the pine transition community can be controlled to reduce the use of ground 

water. Controlled burning is one method, but only 

severe burning that destroys the litter prevents vigorous 

resprouting of the shrubs of this community. (Little, 

1953; Little and Moore, 1953.) This method alone 

probably would be impractical as a method of control. 

Egler (1949) found that proper spraying with herbicides kills Kalmia angustifolia, which is the dominant 

shrub and probably one of the major users of ground 

water in the pine transition community. The combined 

use of controlled burning and herbicide spraying probably would be the most efficient method of controlling
C24 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

shrub density in this community. Much more needs to 

be known of the water requirements of the phreatophytes and other plants in the Pine Barrens before 

adequate measures can be devised to control or reduce 

their use of water.

EFFECTS OF FIRE 

EFFECTS ON BOOTS AND RHIZOMES

Because of the long history of frequent fires in the 

region, all shrubs of the Pine Barrens undoubtedly have 

the ability to recover after burning. Lutz (1934) 

studied the effects of fire on the pines and some of the 

oaks of the Pine Barrens but did not include any of 

the shrub species. The oaks (Quercus Uicifolia. 

Q. marilandica, and Q. prin&ides) sprout vigorously 

after a fire. This recovery is probably related to the 

massive taproot found in these species.

The rhizomatous shrub species also recover after 

burning, but the rhizomes that occur in the A0 horizon 

are susceptible to fire damage. Parts of the roots or 

rhizomes of all the rhizomatous species except Oomptonia peregrina var. asplenifolia, Lyonia mariana, and 

Vaccinium vacillans extend into the A0 horizon. A 

severe ground fire usually consumes all the organic matter on the surface of the soil, damaging or completely 

destroying the part of the rhizome in the A0 horizon. 

Such a fire could separate rhizome systems, and it is 

therefore impossible to determine the original extent of 

clones of most species. The comp act clone of L. mariana 

(fig. 8) described previously was the only relatively 

complete clone found. A contributing factor to the 

existence of this clone probably is the fact that the 

rhizomes of this species rarely occur in the A0 horizon.

A wildfire in July 1955 burned across several of the 

vegetation lines and quadrats established by McCormick 

on McDonalds Branch watershed. Six of these burned 

upland quadrats were resurveyed in October 1955, 

October 1956, and September 1957. Table 12 shows the 

effect of this fire on Vaccinium vacillans and Gaylnsmcia bacoata, and their recovery after the fire. The 

data represent the average percentage of shrub cover 

on six lines each 10 meters long, and the data for 

unoccupied space represent the average percentage of 

bare space on these same lines. G. baccata made up a 

greater percentage of cover than V. vacillans on the 

original survey. Both species had a very low cover 

3 months after the burn (first resurvey). V. vacillans 

contributed more to the cover than G. baccata 15 months 

after the fire (second resurvey); 26 months after the fire 

(third resurvey) there was more than twice as much 

V. vacillans as G. baccata and the amount of G. baccata 

cover had decreased since the previous survey. The 

summer of 1957 was extremely dry and many of the

Species or unoccupied space

Original

cover

38.2

29.9

21.8

First, 

Oct. 1955

4.8

2.3

86.8

Resurvey

Second, 

Oct. 1956

11.7

15.5

62.3

Third, 

Sept. 1957

7.7

18.2

60.7

aerial stems of the shrubs on the burned area appeared 

to be dead at the time of the third resurvey. The 

mortality rate of G, baccata stems was several times 

that of V. vacillans. Thus V. vacillans not only recovers from fire more quickly, as reported by Buell and 

Cantlon (1953), but it apparently is also more drought 

resistant than G. baccata.

TABLE 12. Effect of July 1955 wildfire on shrub cover 

[Figures are average percentage cover of 6 lines 10 meters long]

Differences in the positions of the rhizomes and the 

depth of roots most probably explain this difference in 

ability to survive after a fire and drought. The rhizome of Vaccinium' vacillans almost always grows only 

in the mineral soil but parts of the rhizome of Gayl/ussacia baccata occur in the AO soil horizon. Any ground 

fire, no matter what its intensity, would damage the 

rhizomes of G. baccata much more than those of V. 

vacillans. Well-developed roots of V. vacillans usually 

extend 25-48 inches deep in upland areas but roots of 

G. baccata seldom extend deeper than 6-8 inches. The 

deeper, better developed roots of V. vacillans may be the 

most important factor in this greater fire and drought 

resistance because a fire or extreme drought dries the 

surface part of the soil below the wilting point. Because the deeper roots of V. vacillans extend into soil 

that may not be so extremely dry, they are able to absorb 

moisture and maintain the upper parts of the plants. 

The shallower roots of G. baccata, however, are confined 

to the upper soil which may become too dry for the roots 

to be able to absorb water.

Leach (1925, 1956) reported a similar difference in 

fire resistance of two species. In Great Britain's heath 

lands, Call/ana vulgaris is generally the dominant plant, 

but after a fire Vaccinium myrtillus, which has roots 

and rhizomes that are 8-9 inches deep, sprouts vigorously. Specht and Eatson (1957) found that most 

of the heath species in Australia have their perennating 

buds below the surface and are able to survive a fire even 

though the aerial parts are destroyed.

EFFECTS ON GROUND-WATER SUPPLIES

Controled burning is known to reduce the shrub cover 

in the New Jersey Pine Barrens (Buell and Cantlon, 

1953; Little and Moore, 1949,1953). The present study 

indicates that the A0 and A! horizons contain a large 

proportion of the total roots in the profile and that many
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C25

of these roots are shrub roots in areas having a good 

shrub cover. This concentration of roots near the surface, especially in unburned areas, may absorb most of 

the water from light rains during the growing season 

and prevent it from being stored in the soil and from 

eventually reaching the lower soil horizons or the water 

table.

Besides reducing shrub cover, controlled burning also 

reduces the amount of litter. In many burned areas, 

however, the litter is replaced by mosses. Moul and 

Buell (1955) found that this cushion of moss absorbed 

and held as much as one-half inch of water. The 

amount of water retained by litter in unburned areas of 

the Pine Barrens is also approximately one-half inch 

(Bernard, 1963). Thus, a rain of more than one-half 

inch would be required to wet the soil under a moss 

cushion or a well-developed layer of litter. In Wisconsin, Curtis (1960) found that both hardwood and 

pine litter 2-3 inches thick retained more than 90 percent of the moisture of storms whose total precipitation 

was one-quarter inch or less and retained approximately 

65 percent of the moisture of storms of V4~% inch.

Comparisons of areas with and without shrub cover 

on the same soil type clearly show that an area with no 

shrubs contains far fewer roots, especially in the surface 

horizons. Since the litter layer of an unburned area 

absorbs approximately the same amount of moisture as 

the cover of mosses that may develop after burning, then 

the differences between burned and unburned sites, as 

far as water supply is concerned, probably would be 

related to changes in the shrub layer. The reduced 

number of shrub roots in the soil (decreasing absorption) together with the reduced shrub cover above 

ground (reducing interception) probably would increase the amount of water penetrating to the lower soil 

layers during the growing season. The influence of a 

good stand of shrubs on soil moisture was shown by 

Eschner (1960) in an oak-pine area in eastern Pennsylvania similar to the Pine Barrens. The top 18 inches 

of soil under ericaceous-shrub ground cover was drier 

than that under any other vegetation type; this fact 

indicates that ericaceous shrubs are the major users of 

soil moisture in the upper part of a soil. The species 

of shrubs studied by Eschner also occur in the Pine 

Barrens.

Use of water during the growing season is not the 

only factor influencing ground-water supplies, however. 

Because much of the recharge of the water table takes 

place during the winter when there is little transpiration, the density of shrub roots in the upper horizons 

may not affect water-table levels much. Furthermore, 

tree roots in the deeper layers of the soil may utilize 

much of the water that penetrates beyond the surface regardless of the amount of shrub cover. McQuilkin 

( 1935) found that mature pitch pines often had taproots 

with well-developed laterals as deep as 8 feet in the 

sandy soil of the New Jersey Pine Barrens. Detailed 

soil-moisture studies at various depths in burned and 

unburned areas are needed to determine how shrub roots 

affect the amount of water reaching the water table.

TABLE 13. Scientific and common names of plants of the Pine 

Barrens mentioned 'in the paper

Scientific name

Trees :

Acer rubrum var. trilobum _____

Chamaecyparis thyoides ____ _ _

Nyssa sylvatica _________ ___ .

Pinus echinata- _ _ 

P. rigida _________________ _ __

Quercus alba ______ ________

Q. coccinea __________ _ _ __ _ .

Q. marilandica- _ _ _ _ 

Q. primi^s _______________ _

Q. velutina ____________________

Shrubs :

Amelanchier canadensis _ ___ 

Ghamaedaphne calyculata __ __ 

Clethra alnifolia ______________ .

Comptonia peregrina var. asplenifolia ______________________

Galtheria procumbens _ __ ___

Gaylussacia baccata ___________

G. dumosa _____________ ______ .

G. frondosa ___________________

Hudsonia ericoides ____________ .

Ilex glabra _______________ _ __

I. verticillata ___________ . 

Kalmia angustifolia ___ _ _ __ .

K. latifolia ____________________

Leiophyllnm buxifolium ____ __

Leucotlioe racemosa ______ _ .

Lyonia ligustrina ______________

L. mariana ____________ - 

Myrica pensylvancia ____ __

Pyrus arbutifolia _____ _____

P. melanocarpa _________ _ _ _

QucrcHS ilicifolia ___ _ _ ____

Q. prinoides ___________________

Rhododendron viscosum ________

Vaccinium angustifolium _______

V. corymbosum ________ _____

V. vacillans ________ _ _____

Herbaceous plants :

Carex pensylvanica _______ _ __

Common name

Red maple

Southern white cedar 

Black gum 

Shortleaf pine 

Pitch pine 

White oak 

Scarlet oak 

Blackjack oak 

Chestnut oak 

Black oak

Serviceberry 

Leatherleaf 

Sweet pepperbush

Sweet fern

Teaberry

Black huckleberry

Dwarf huckleberry

Dangleberry

Golden heather

Inkberry

Black alder

Sheep laurel

Mountain-laurel

Sand myrtle

Fetterbush

Maleberry

Staggerbush

Bayberry

Red chokeberry

Black chokeberry

Scrub oak

Dwarf chestnut oak

Swamp honeysuckle

Low sweet blueberry

Highbush blueberry

Lowbush blueberry

Sedge
C26 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

TABLE 14. Summary of the characteristics of the root and rhizome systems of the Pine Barrens shrubs studied 

IVA, very abundant; A, abundant; C, common; K, rare; VR, very rare; AB, absent; N, no rhizomes]

Shrub or tree

Comptonia peregrina var. asplenifolia. ...

Gauttheria procumbens... . .......... ..

Gaylussaciabaccata.. ...... . ..... ......

Hudsonia erkoides... . ... ..... .. ..

K. Mifolia...... ... .. ..... .............

Leiophyllum buxifolium ..................

Quercus Uicifolia ............ ............

Q. marilandica ..... .... . ... .......

Vaccinium angusti folium.... ..... . ....

Abundance

Upland

VR--. 

R 

R.. __ ....

A.. 

A. ..

C. ...... ....

VR.- ....

R 

R... ..... 

VR.- 

R 

VR... 

VR-.- .

VA.._ 

C....... ....

C 

R ... 

A. ..

Transition 

zone

R 

C ...

R ... .....

A ..... .

C ......

A...... 

AB... 

C 

VA

R_ ....

R ... C . _ .

C... 

R 

R ..

R. ..... .

AB--. ...

~R. ..........

C. ..........

Lowland

R .... ....

A 

R 

C 

AAB..-. - .

r-.

a. ......... .

AB. .. ......

C_ 

R- .

VR-. .

R .... ....

AB.........

AB.. .......

AB... ......

R. 

R .... ...

Rhizome

Diameter 

(inches)

 ,/

14 56

v/3/

M/6 

iz_ai

N. ... 

v 14

N.. 

,

o/ _f i

JL -_?/

N

N 

1^_3/

Depth in 

soil (inches)

0-1- __ n-9

0-2- 

0-1 

0-3 .

0-2 

N. __ 

no

0-1.. 

fUd

N ..... .

0-2 

0-^.. .......

0-1 

N 

N. ...

N.. .........

0-1 

0-6 

Does rhizome grow 

in Ao soil 

horizon?

Yes. 

VPQ

No 

Yes 

Yes.- ...

Yes ...

N... .... 

VAS

Yes.... 

Vpo

N ..

Yes... 

No.. 

Yes 

Yes 

N 

N. ..........

N 

Yes ....

No 

Roots

Depth of 

deepest 

root 

(inches)

4 

30 

10 

1 

8 

4 

6 

24 

40 

30 

6 

4

58 

30 

4 

36 

36 

48 

6 

48

Do roots 

ever extend 

to the water 

table?

Yes. .

Yes 

No.... ..... .

Yes ...

Yes... 

Yes.. .

No ....

Yes ...

Yes.. ....

Yes. 

No. .

Yes ..

Yes.... ... ..

Yes ....

Yes...... ...

No... ... 

No.. ....

Yes. 

Yes...... ...

No 

Aerial stems, 

distance 

apart on 

the rhizome 

(inches)

6-24 

3-96 

2-12 

0.2-5 

12-48 

3-72 

N 

6-18 

2-24 

6-24 

N 

As much as 

156 

12-48 

6-36 

6-24 

N 

N 

N 

6-18 

12-48

SUMMARY

The deep sandy strata under the Pine Barrens of New 

Jersey have been proposed as a future source of water. 

Controlled burning is being used to increase the proportion of pine in the oak-pine forests of the region. This 

burning also greatly reduces the shrub cover. In 1951, 

the Pine Barrens hydrological research project was initiated to determine how this change in forest composition will affect ground-water supplies. This paper, as 

part of the project, (1) describes the root and rhizome 

systems of the upland and transition zone shrubs of the 

region and (2) compares the vertical distribution of 

roots in seven upland and transition zone soil types on 

two experimental watersheds in the Lebanon State 

Forest.

Vaccinium vaeillans and Gaylussacia baccata are the 

most common upland shrubs, and, of the two, V. vacillans is the more fire and drought resistant. The rhizomes of V., vacillans are confined to the mineral soil 

and its roots extend 25-48 inches deep, but both the roots 

and rhizomes of G. baccata are superficial and often occur in the A0 horizon. A ground fire that destroys the 

A0 horizon or a drought that dries the surface soil would 

be expected to damage G. baccata more than V. 

vacillans.

The roots of Quercus Uicifolia and Vaccinium vacillans extend rather deep in upland areas, but in the pine 

transition community where the water table is shallow 

the roots are superficial. The roots of these species apparently cannot tolerate the poor aeration and other 

conditions associated with the saturated zone of the 

water table.

Kalmia angustifolia and Lyonia mariana have roots 

that extend to the water table where it is 2-5 feet below

the surface. Many other species may or may not have 

roots that extend to the water table. The use of water 

in this area by these and other species is not a problem 

at present, but when ground-water supplies fail to adequately supply the demands, the amount used by plants 

will have to be reduced. One method of reducing this 

use is to lower the water table beyond the roots of the 

plants, and another is to remove species that are heavy 

users of ground water or replace them with species that 

use less water.

The highest total number of tree and shrub roots were 

found in the Lakehurst sand; the Lakewood sand, clay 

substratum variant; the Lakeland sand; and the 

Downer sand. The latter three soils have thin, imperfectly bleached A2 horizons.

The A0 horizon, where it is present, contains the highest number of roots per square foot, and the AI horizon 

contains the next highest number in all soil types. 

More than 85 percent of the shrub roots and rhizomes 

are found in the A0 and A± horizons. The number of 

all roots decreases sharply from the A± to the A2 horizon. In the well-drained upland soils the number of 

roots per square foot increases from the A2 to the BI 

horizon and decreases below that. This increase in the 

B± horizon was not found in the imperfectly or poorly 

drained soils.

The number of roots in the B horizon decreased downward in all soils except the Lakewood sand, clay substratum variant, which had a 2-foot-thick layer of clay 

below a thin B2 horizon. Clay evidently favors root 

development and counterbalances the normal downward 

decrease in number of roots.

A large proportion of the numerous roots in the A0 

and AI horizons are shrub roots and rhizomes at all
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C27

sites having a good shrub cover. This concentration of 

shrub and other roots near the surface may absorb much 

of the water from light rains during the growing season, and thus prevent it from reaching the lower soil 

levels or the water table. The sites with no shrubs had 

significantly fewer roots in all horizons than any site 

with shrubs. A decrease in shrub cover caused by controlled burning and the resultant decrease in the number of roots might permit an increased amount of water 

to reach the water table.

SELECTED REFERENCES

Aldrich-Blake, R. N., 1929, Recent research on the root systems

of trees: Forestry, v. 3, p. 66-70. 

Anderson, C. H., and Cheyney, E. G., 1934, Root development in

seedlings in relation to soil texture: Jour. Forestry, v. 32,

p. 32-34. 

Bacho, Andrew B., 1955, A geologic and preliminary hydrologic

comparison of McDonalds Branch and Middle Branch

watersheds, Lebanon State Forest, New Jersey: Iowa

Univ., unpub. M.S. thesis. 

Barksdale, Henry C., 1952, Ground water in the New Jersey

Pine Barrens area: Bartonia, v. 26, p. 36-38. 

Beckenbach, Joseph H., and Gourley, J. H., 1933, Some effects of

different cultural methods upon root distribution of apple

trees: Am. Soc. Hort. Sci. Proc., v. 3, p. 202-204. 

Bernard, John M., 1963, Forest floor moisture capacity of the

New Jersey Pine Barrens: Ecology, v. 44, p. 574-576. 

Braun, E. Lucy, 1936, Notes on root behavior of certain trees

and shrubs of the Illinoian till plain of southwestern Ohio:

Ohio Jour. Sci., v. 36, p. 141-146. 

Buell, Murray F., 1955a, Origin and development of the Pine

Region hydrological project: Am. Cranberry Growers Assn.

Proc., 1955, p. 10-13.

 1955b, New botanical problems in the New Jersey Pine 

Barrens: Torrey Bot. Club Bull. 82, p. 237-241.

Buell, Murray F., and Cantlon, John, E., 1950, A study of two 

communities of the New Jersey Pine Barrens and a comparison of methods: Ecology, ¥. 31, p. 567-586.

 1953, Effects of prescribed burning on ground cover in 

the New Jersey Pine Region: Ecology, v. 34, p. 520-528.

Biigsen, M., and Munch, E., 1929, The structure and life of trees: 

New York, John Wiley & Sons, Inc., 436 p.

Cannon, W. A., 1911, Root habits of desert plants: Carnegie 

Inst. Washington Pub. 131, 96 p.

Cantlon, John E., 1951, A preliminary investigation of the influence of prescribed burning on soil water supplies in South 

Jersey: Am. Cranberry Growers Assn. Proc., 1951, p. 18-26.

Cantlon, John E., and Buell, Murray F., 1952, Controlled-burning, its broader ecological aspects: Bartonia, v. 26, p. 48-52.

Chadwick, L. C., Bushey, D., and Fletcher, G., 1937, Root 

distribution studies: Am. Soc. Hort. Sci. Proc., v. 35, 

p. 734-738.

Cheyney, E. G., 1929, A study of the roots in one square yard of 

jack pine forest: Jour. Forestry, v. 27, p. 546-549.

 1932, The roots of a jack pine tree: Jour. Forestry,

v. 30, p. 929-932. 

Coile, T. S., 1937, Distribution of forest tree roots in North

Carolina Piedmont soils: Jour. Forestry, v. 35, p. 247-257.

Cooper, W. S., 1926, Vegetational development upon alluvial fans

in the vicinity of Palo Alto, California: Ecology, v. 7,

p. 1-30. 

Coville, F. W., 1910, Experiments in blueberry culture: U.S.

Dept. Agriculture, Bur. Plant Industry Bull. 193. 

Cranmer, Carl B., 1952, Future of the Pine Barrens: Bartonia,

v. 26, p. 53-60. 

Croft, A. R., 1950, A water cost of runoff control: Jour. Soil

and Water Conserv., v. 5, p. 13-15. 

Curtis, Willie R., 1960, Moisture storage by leaf litter: U.S.

Forest Service, Lake States Forest Expt. Sta. Tech. Notes

577, 2 p. 

Diebold, C. H., 1933, Root distribution and penetration of soil

layers : Jour. Forestry, v. 31, p. 481-482. 

Duncan, D. B., 1955, Multiple range and multiple F tests:

Biometrics, v. 11, p. 1-42. 

Duncan, W. H., 1941, A study of root development in three soil

types in the Duke forest: Ecol. Mon., v. 11, p. 141-164. 

Dunford, E. G., and Fletcher, B. W., 1947, Effect of removal of

streainbank vegetation upon water yields: Am. Geophys.

Union Trans., v. 28, p. 105-110. 

Eames, A. J., and MacDaniels, L., 1947, Introduction to plant

anatomy : New York, McGraw-Hill Book Co., 427 p. 

Egler, Frank E., 1949, Herbicide effects in Connecticut vegetation, 1948: Ecology, v. 30, p. 248-256. 

Eschner, Arthur R., 1960, Effect of scrub oak and associated

ground cover on soil moisture: U.S. Forest Service,

Northeast Forest Expt. Sta. Paper 133, 16 p. 

Fernald, M. L., 1950, Gray's manual of botany: 8th ed., New

York, American Book Co., 1632 p. 

Fletcher, H. C., and Rich, L. R., 1954, Discussion of "Use of

water by native vegetation versus grasses and forbs on

watersheds" by F. J. Veihmeyer: Am. Geophys. Union

Trans., v. 35, p. 652-655. 

Fuller, H. J., and Tippo, Oswald, 1954, College botany: revised

ed., New York, Henry Holt and Co., 993 p. 

Garin, G. I., 1942, Distribution of roots of certain tree species in

two Connecticut soils: Connecticut Agr. Expt. Sta. Bull.

454, 167 p. 

Haasis, F. W., 1921, Relations between soil type and root form

of western yellow pine seedlings: Ecology, v. 2, p. 292-303. 

 1923, Frost heaving of western yellow pine seedlings:

Ecology, v. 4, p. 378-390. 

Hall, I. V., 1957, The tap root in lowbush blueberry: Canadian

Jour. Botany, v. 35, p. 933-935. 

Hall, I. V., and Mack, G. J. S., 1960, Weeds: Canada Dept. Agr.,

Blueberry Substa., Tower Hill, New Brunswick, Progress

Rept. 1954-59, p. 18. 

Harshberger, John W., 1916, The vegetation of the New Jersey

Pine Barrens: Philadelphia, Christopher Sower Co., 329 p. 

Hewlett, John D., and Hibbert, Alden R., 1961, Increases in

water yield after several types of forest cutting: Internat.

Assoc. Sci. Hydrology Quarterly Bull., September 1961,

p. 5-17. 

Heyward, Frank, 1933, The root system of longleaf pine on the

deep sands of western Florida: Ecology, v. 14, p. 136-148. 

Hoffman, M. B., and Schlubatis, G. R., 1928, The significance of

soil variation in raspberry culture: Michigan Agr. Expt.

Sta. Spec. Bull. 177, 20 p.
C28 HYDROLOGY AND ECOLOGY, PINE BARRENS, NEW JERSEY

Holm, T., 1929, Anatomy of certain species of Ilex of the sections 

Aquifolium and Prinos: Am. Jour. Sci., v. 18, p. 497-504.

Hoover, M. D., 1944, Effect of removal of forest vegetation on 

water yields: Am. Geophys. Union Trans., v. 25, p. 969-975.

Hopkins, H. T., Jr., and Donahue, R. L., 1939, Forest tree root 

development as related to soil morphology: Am. Soil Sci. 

Soc. Proc., v. 4, p. 353.

Korstian, C. F., and Coile, T. S., 1938, Plant competition in 

forest stands: Duke Univ. School of Forestry Bull. 3, 125 p.

Kiimmel, H. B., 1940, The geology of New Jersey [Revision of 

Lewis, J. V., and Kiimmel, H. B., 1914]: New Jersey Dept. 

Conserv. and Devel. Bull. 50, 203 p.

Leach, William, 1925, The vegetation of Derwent Falls, Cumberland: Birmingham [England] Nat. Hist, and Philos. 

Soc. Proc., v. 15, p. 85-93.

 1956, Plant Ecology: New York, John Wiley & Sons,

106 p. 

Little, Silas, Jr., 1952, Silvicultural objectives and methods on

upland sites in the New Jersey Pine Region: Bartonia, v.

26, p. 44-47.

 1953, Prescribed burning as a tool of forest management 

in the northeastern states: Jour. Forestry, v. 51, p. 

496-500.

Little, Silas, Jr., Alien, J. P., and Moore, E. B., 1948, Controlled 

burning as a dual-purpose tool of forest management in 

New Jersey's Pine Region: Jour. Forestry, v. 46, p. 810-819.

Little, Silas, Jr., and Moore, E. B., 1945, Controlled burning in 

south Jersey's oak-pine stands: Jour. Forestry, v. 43, p. 

499-506.

 1949, The ecological role of prescribed burns in the pineoak forests of southern New Jersey: Ecology, v. 30, p. 

223-233.

 1953, Severe burning treatment tested on lowland pine 

sites: U.S. Forest Service Northeast Forest Expt. Sta. Paper 

64, 11 p.

Livingston, B. E., 1906, Relation between root growth and tops: 

Bot. Gaz. v. 41, p. 139-143.

Love, L. D., 1955, The effect on streamflow of the killing of 

spruce and pine by the Englemann spruce beetle: Am. 

Geophys. Union Trans., v. 36, p. 113-118.

Lunt, H. A., 1934, Distribution of soil moisture under isolated 

forest trees: Jour. Agr. Research, v. 49, no. 8, p. 695-703.

Lutz, H. J., 1934, Ecological relations in the pitch pine plains 

of southern New Jersey: Yale Univ. School Forestry Bull. 

38, 80 p.

Lutz, J. E., Ely, J. B., and Little, Silas, Jr., 1937, The influence 

of soil profile horizons on root distribution of white pine; 

Yale Univ. School Forestry Bull. 44, 75 p.

Mahlstede, J. P., and Watson, D. P., 1952, An anatomical study 

of adventitious root development in stems of Vaccinium 

corybosum: Bot. Gaz., v. 113, p. 279-284.

Markley, Marco, 1955, National cooperative soil studies, watershed research project areas, Middle Branch and McDonalds 

Branch, Lebanon State Forest, New Jersey: New Brunswick, N.J., Soil Conserv. Ser., 8 p.

Martin, R. J., and Corbin, E., [no date], Climatic summary of 

the United States, Section 90, New Jersey, summary to 1930 

inclusive: U.S. Dept. of Agriculture Weather Bureau.

McCormick, Jack, 1955, A vegetation inventory of two watersheds in the New Jersey Pine Barrens: Rutgers Univ. 

unpub. Ph. D. thesis.

McQuilkin, W. E., 1935, Root development of pitch pine, with 

some comparative observations on shortleaf pine: Jour. 

Agr. Research, v. 51, p. 983-1016.

Meinzer, O. E., 1927, Plants as indicators of ground water: 

U.S. Geol. Survey Water-Supply Paper 577, 95 p.

Moore, E. B., 1939, Forest management in New Jersey: New 

Jersey Dept. Conserv. and Devel., Div. Forest and Parks, 

55 p.

Moore, E. B., Smith, G. E., and Little, S., 1955, Wildfire damage 

reduced on prescribe-burn areas in New Jersey: Jour. 

Forestry, v. 53, p. 339-341.

Moul, Edwin T., and Buell, Murray P., 1955, Moss cover and rainfall interception in frequently burned sites in the New Jersey 

Pine Barrens: Torrey Bot. Club Bull. 82, p. 155-162.

Costing, H. J., and Reed, J. F., 1952, Virgin spruce-fir forests in 

the Medicine Bow Mountains, Wyoming: Ecol. Mon., v. 22, 

p. 69-91.

Oskamp, J., and Batjer, L. P., 1932, Size, production, and rooting 

habits of apple trees on different soil types in the Hilton 

and Morton area, Monroe Co: Cornell Univ. Agr. Expt. 

Sta. Bull. 550, 45 p.

Partridge, N. L. and Veatch, J. O., 1931, Fertilizers and soils 

in relation to concord grapes in southwestern Michigan: 

Michigan Agr. Expt. Sta. Tech. Bull. 114, 42 p.

 1932, The relation between soil profile and root development of fruit trees: Michigan Agr. Expt. Sta. Quarterly 

Bull. 14, p. 200-207.

Pinchot, Clifford, 1899, A study of forest fires and wood production in southern New Jersey, in Annual report of the 

State Geologists: New Jersey Geol. Survey Ann. Rept., 

1898: Trenton, New Jersey Geol. Survey, 100 p.

Preston, E. J., Jr., 1942, Roots of juvenile lodgepole pine: Jour. 

Forestry, v. 40, p. 966-967.

Robinson, T. W., 1951, Phreatophytes and their relation to water 

in western United States: Am. Geophys. Union Trans., v. 

32, p. 333.

 1958, Phreatophytes: U.S. Geol. Survey Water-Supply 

Paper 1423, 84 p.

Sartz, Richard S., 1951, An objective look at the vegetationstreamflow relationship: Jour. Forestry, v. 49, p. 871-875.

Scully, Norbert, J., 1942, Root distribution and environment in 

a maple-oak forest: Bot. Gaz., v. 103, p. 492-517.

Smith, W. O., and Stallman, R. W., 1955, Measurement of permeabilities in ground water investigations: ASTM Spec. 

Tech. Pub. 163; p. 98-12*2.

Snedecor, George, W., 1956, Statistical methods: 5th ed., Ames, 

Iowa State Coll. Press, 534 p.

Specht, R. L., and Ratson, Patricia, 1957, Dark Island Heath 

(Ninety-Mile Plain, South Australia), [pt] 3. The root 

systems: Australian Jour. Bot., v. 5, p. 103-114.

Stephenson, R. E., and Schuster, C. E., 1937, Physical properties of soils that affect plant nutrition: Soil Sci., v. 44, p. 

23-36.

Stoeckler, J. H., and Kleunder, W. A., 1938, The hydraulic 

method of excavating the root systems of plants: Ecology, 

v. 19, p. 255-269.

Stone, Witmer, 1912, The plants of southern New Jersey 

with especial reference to the flora of the Pine Barrens and 

the geographic distribution of the species: Ann. Rept. New 

Jersey State Mus., 1910, p. 23-828.

Stout, Benjamin B., 1956, Studies of the root systems of deciduous trees: Black Rock Forest [New York] Bull. 15, 45 p.

Swetloff, N. F., 1931, Issledovanie vliyania usloviy mestoproizrostania na kornevouyu sistemu sosny v institutskom (b. 

pargolovskom) uchebnom lespromchoze [Investigation of 

the influence of the site conditions on the root system of 

pine in the experimental forest of Leningrad Forest
DISTRIBUTION OF ROOTS AND RHIZOMES IN SOIL TYPES C29

Academy] Troudy lestochnicheskoy acad. lesovodstvennyi

tziki Leningrad, v. 1, no. 38, p. 103-126. 

Tedrow, J. C. F., 1952, Soil conditions in the Pine Barrens of

New Jersey: Bartonia, v. 26, p. 28-35. 

Tharp, B. C., and Muller, C. H., 1940, A rapid method for

excavating root systems of native plants: Ecology, v. 21,

p. 347-350.

Trevett, M. F., 1956, Observations on the decline and rehabilitation of lowbush blueberry fields: Maine Agr. Exp. Sta.

Misc. Pub. 626, 21 p.

Trousdell, K. B., and Hoover, M. D., 1954, A change in groundwater level after clear cutting of loblolly pine in the coastal

plain: Jour. Forestry, v. 53, p. 493-498. 

Turner, L. M., 1936, A comparison of roots of southern shortleaf

pine in three soils : Ecology, v. 17, p. 649-658. 

U.S. Dept. of Agriculture, 1951, Soil survey manual: U.S. Dept.

Agr. Handb. 18, 503 p. 

Veihmeyer, F. J., 1953, Use of water by native vegetation versus

grasses and forbs on watersheds: Am. Geophys. Union

Trans., v. 34, p. 201-212. 

Waterman, W. G., 1919, Development of root systems under

dune conditions: Bot. Gaz. v. 68, p. 22-53.

Weaver, J. E., 1919, The ecological relations of roots: Carnegie

Inst. Washington Pub. 286,128 p. 

 1920, Root development in the grassland formation.

Carnegie Inst. Washington Pub. 292,151 p. 

Wenzel, L. K., 1942, Methods for determining permeability of

water-bearing materials: U.S. Geol. Survey Water-Supply

Paper 887, 192 p. 

White, A. E., 1941, Climate of New Jersey in Climate and man:

U.S. Dept. Agriculture Yearbook, 1941, p. 1002-1010. 

Wilm, H. G., and Dunford, E. G., 1948, Effect of timber cutting

on water available for streamflow from a lodgepole pine

forest: U.S. Dept. Agriculture Tech. Bull. 968, 43 p. 

Woods, Frank W., 1957, Factors limiting root penetration in

deep sands of the southeastern coastal plain: Ecology, v.

38, p. 357-359. 

Yeager, A. F., 1935, Root systems of certain trees and shrubs

grown on prairie soils: Jour. Agr. Research, v. 51, p. 1085-

1093. 

Youngken, H. W., 1919, The comparative morphology, taxonomy,

and distribution of the Myricaceae of the eastern United

States: Univ. Pennsylvania Bot. Lab. Contr. 4, p. 339-400.