Tall Trees of Chase Creek Woods
Colby B. Rucker
Chase Creek Woods is located at Arnold, in the highlands of the Severn River, in Anne Arundel County, Maryland. Anne Arundel has been called the northernmost county in southern Maryland; it has a variety of soil types and corresponding plant communities, but most are typical of the Mid-Atlantic Coastal Plain, where southern red oak, willow oak, sweet gum, pitch pine and sweetbay magnolia abound.
Chase Creek Woods differs in that these species are rarely encountered. The topography and soils are quite varied, offering suitable habitat for more than fifty native tree species. Elevations range from tidewater to 140 feet. The soils are sandy loam, silt loam, loamy sand, and alluvium. On the highest elevations, silt loams are underlaid by nearly impervious subsoils, thereby supporting plants similar to those on lowland sites. Sandy intermediate-elevation terraces support more xeric plant communities. Deep ravines with rich soils and cool exposures form outliers for vegetation more typical of cove hardwood regimes above the Fall Line.
Much of the Chase Creek watershed was cleared over three hundred years ago for the growing of tobacco and, more recently, for residential development. Perhaps half is still wooded, but highly fragmented. The existing wooded areas are old fields, narrow ridges, steep slopes, ravines and wetlands. Although some areas have been undisturbed for 75-100 years, logging has occurred in the past, resulting in a greater prevalence of tuliptrees on many sites. Despite these impacts, Chase Creek Woods is one of the countys outstanding natural areas.
Beginning in April 2000, approximately 150 acres of forest were studied, consisting of four tracts in private ownership. The tallest examples of 56 taxa were measured, including seven naturalized species. Additional native species were seen, but were not included, being outside the study properties, immature (under fifteen feet in height), or of uncertain origin. Tree circumferences were measured at 4.5 feet above average grade. Heights of smaller trees were measured directly with a telescoping aluminum pole. Heights of taller trees were determined with a laser rangefinder in conjunction with a clinometer, using a pole for an accurate sighting point above screening vegetation.
The following trees are the tallest of each species measured within the study area. Although specimens with larger trunks were encountered, most were not as tall. The modest size of the study area suggests a similar genetic height potential within each species; therefore, the tallest examples usually occur on sites most conducive to height development for that species. While some species are present in very limited numbers, the maximum heights still reflect those species place in the forest structure at this time.
These species have been divided into six groups. It is useful to consider what the trees within each group have in common. Each group has been named. This is not a description of forest types; a group may include species from both upland and lowland regimes. The approach taken here is more structural, and indicates typical canopy position for maximum height development. This yields a height profile for the entire study area. In the following list, the maximum height for each species is followed by the cbh (circumference at breast height, or 4.5 feet) for that specimen. A letter indicates the four study properties, which are unnamed, to insure privacy. The habitat, soil and exposure for each specimen often show distinct patterns, which indicate the influence of those factors upon maximum height.
Species Height CBH Tract Habitat Soil Exposure
Mesic dominants: Low-slope position, east or north facing; circumneutral soils.
Tuliptree Liriodendron tulipifera 157.6 9 7.5 A cool ravine, base of slope moist sandy loam NE
Northern red oak Quercus rubra 137.4 22 0 A cool ravine, mid-slope sandy loam NE
Black oak Quercus velutina 135.6 10 2.5 A small ravine, low-slope sandy loam E
American sycamore Platanus occidentalis 132.3 6 3.0 A deep ravine, bottom moist sandy loam E
White ash Fraxinus americana 132.0 8 8.5 A cool ravine, base of slope moist sandy loam NE
Pignut Carya glabra 124.1 5 5.0 A deep ravine, low-slope sandy loam SE
Sub-mesic dominants: Mixed slope position, often south-facing, soils more acidic .
Chestnut oak Quercus prinus 124.8 5 6.0 B broad ravine, low-slope sandy loam W
White oak Quercus alba 121.4 8 4.0 A ravine, low-slope sandy loam SE
American beech Fagus grandifolia 119.5 10 3.0 B broad ravine, low-slope sandy loam E
Mockernut Carya tomentosa 117.2 5 11.0 A dry ravine, broad upper swale sandy loam SE
Black cherry Prunus serotina 116.5 6 7.0 C upland, old-field silt loam E
Red maple Acer rubrum 110.3 7 3.0 C low-slope/swamp interface loam/org./alluvium SW
Bitternut Carya cordiformis 108.3 5 11.5 C mixed woods, mid-slope sandy loam S
Black walnut Juglans nigra 107.1 7 10.5 B ravine, mid-slope opening sandy loam SE
Sweetgum Liquidambar styraciflua 103.0 5 9.5 B upland, old-field sandy loam S
Blackgum Nyssa sylvatica 98.5 5 6.0 B swale, low end loamy sand W
Dry-mesic: Usually sandy soils, south-facing.
Shortleaf pine Pinus echinata 105.0 5 8.0 B mixed woods, mid-slope sandy loam SE
Southern red oak Quercus falcata 103.7 5 4.0 B terrace, middle position loamy sand NW
Scarlet oak Quercus coccinea 103.2 7 6.5 C terrace, upper position loamy sand NW
Sand hickory Carya pallida 88.9 5 3.5 C mid-slope below terrace loamy sand S
Virginia pine Pinus virginiana 85.2 4 6.5 B upland, mixed woods sandy loam S
Bigtooth aspen Populus grandidentata 81.9 2 7.0 C terrace, middle, opening loamy sand S
Pitch pine Pinus rigida 77.5 3 10.0 C terrace, upper position loamy sand W
Transitional zones: Solar access usually provided at upland/wetland or forest/field interface.
Ailanthus (natd) Ailanthus altissima 91.0 5 8.5 D upland, interface influence silt loam E
Sassafras Sassafras albidum 81.0 3 2.5 C old-field, upper slope silt loam E
Black locust Robinia pseudoacacia 79.9 3 6.0 C low-slope, disturbed, interface sandy loam SE
Black willow Salix nigra 76.8 2 9.5 C swamp/slope interface alluvium SW
Mazzard cherry (natd) Prunus avium 73.2 2 9.5 C mid-slope, disturbance loamy sand SE
Paulownia (natd) Paulownia tomentosa 71.9 5 0 C upper slope, disturbance loamy sand SE
Willow oak Quercus phellos 66.2 2 5.0 D upland, old-field interface silt loam E
American elm Ulmus americana 63.4 2 4.0 C upland, old-field, opening silt loam S
Boxelder Acer negundo 59.5 6 5.5 C mid-slope, opening sandy loam S
Persimmon Diospyros virginiana 57.2 3 2.0 D upland, old-field, interface silt loam SE
American holly Ilex opaca 56.6 3 6.0 D upper slope, interface sandy loam S
Eastern redcedar Juniperus virginiana 55.9 4 0.5 D upland, open/interface sandy loam S
American hornbeam Carpinus caroliniana 50.8 2 11.5 C slope above wetland interface loamy sand SE
Saul oak x Quercus saulei 49.2 1 7.0 D mid-slope, opening sandy loam S
Red mulberry Morus rubra 46.4 2 5.0 D upland, interface silt loam S
White mulberry (natd) Morus alba 46.3 1 7.0 D upland, interface silt loam SE
American chestnut Castanea dentata 46.1 3 4.0 B terrace, edge, above interface loamy sand N
Callery pear (natd) Pyrus calleryana 39.2 1 4.5 C low terrace, interface silt loam SW
Mimosa (natd) Albizzia julibrissin 31.5 0 9.5 C low terrace, interface silt loam E
Understory: Solar access often via windthrow openings.
Pawpaw Asimina triloba 36.5 1 4 D upland, mixed woods, opening silt loam W
Flowering dogwood Cornus florida 33.3 1 11.5 C mixed woods, mid-slope sandy loam E
Redbud Cercis canadensis 31.8 2 2.5 D upland, mixed woods, interface silt loam S
Poison sumac Toxicodendron vernix 29.5 1 5.5 C swamp, opening organic/alluvium W
Hazel alder Alnus serrulata 27.7 0 8.0 C swamp, opening organic/alluvium W
Blackhaw viburnum Viburnum prunifolium 27.5 1 4.0 B upper slope, opening sandy loam S
Hercules club Aralia spinosa 26.6 1 2.0 C upland, old-field, opening silt loam E
Staghorn sumac Rhus typhina 20.4 0 9.5 C upland, interface/clearing silt loam NW
Hackberry Celtis occidentalis 19.5 0 8.0 C low slope, interface sandy loam S
Small arborescent specialists: Single-trunked examples of shrubby, shade-tolerant species.
Downy serviceberry Amelanchier arborea 19.7 0 9.0 B terrace, edge, above interface loamy sand N
Spicebush Lindera benzoin 19.0 0 11.5 C upland, old-field, opening silt loam E
Althea (natd) Hibiscus syriacus 19.0 0 8.0 D upland, interface influence silt loam S
Whorled winterberry Ilex verticillata 18.5 0 6.0 C swamp, opening organic/alluvium W
Mountain laurel Kalmia latifolia 17.7 0 9.0 B terrace, edge, above interface loamy sand N
Swamp chestnut oak Quercus michauxii Immature C exposed weedy swale sandy loam S
Post oak Quercus stellata Access not obtained - exposed slope below terrace dry loamy sand SW
Blackjack oak Quercus marilandica Access not obtained - exposed slope below terrace dry loamy sand SW
Winged sumac Rhus copallina Not relocated C cut & fill sandy loam S
Smooth sumac Rhus glabra Not relocated D upland, old-field, interface silt loam S
Witch hazel Hamamelis virginiana Immature C steep mossy swale below terrace loamy sand N
Sugar maple Acer saccharinum Uncertain origin C wet ravine, low slope moist sandy loam E
American linden Tilia americana Uncertain origin B ravine, base of slope sandy loam E
This study indicates that Chase Creek Woods is an important natural area worthy of protection. A height index used by the Eastern Native Tree Society indicates that Chase Creek Woods is the tallest privately-owned woodland known in the eastern United States, having an index of 130.19 feet for the ten tallest species. The variety of habitat supports large examples of nearly fifty native tree species. Twelve are the tallest of their species on record in Maryland: white ash, chestnut oak, American beech, black cherry, red maple, shortleaf pine, American hornbeam, pawpaw, poison sumac, hazel alder, blackhaw and whorled winterberry. The 157.6 tuliptree is one of the tallest trees known to exist in Maryland, being surpassed only by 159.9 and 159.6 tuliptrees at Belt Woods. The tallest examples of seven species are also champions by the point system. In terms of height, girth and spread, the following were listed by the Maryland Forest Service in 2002 as state champions/co-champions: northern red oak, shortleaf pine, poison sumac, hercules club, hazel alder, spicebush, whorled winterberry, and althea. The poison sumac and althea were listed by American Forests as 2002 national champions/co-champions.
The study also shows that laser-derived height indexes can provide valuable data for a variety of forest studies. In the past, tree heights were difficult to determine, especially on steep terrain and in densely forested areas. Faulty techniques also led to inflated measurements, which have limited any scientific use of height data. With laser technology, accurate measurements provide maximum heights for each species, which helps to define their niche in specific environments.
A rather well defined height index exists for each species where sufficient mature examples are available for measurement. Age and trunk diameter are less of a factor than expected, with some slender specimens being as tall, or taller, than well-formed specimens of much greater diameter. Eighteen species exceed 100 feet in height, and the average height of the ten tallest species is 130.19 feet. This maximum height index is very close to Belt Woods, a National Natural Landmark site in Prince Georges County, with an index of 130.97 feet. These species are typical of cove hardwood forests, and are usually on low-slope mesic sites with a generally eastern exposure. Various herbaceous plants serve as indicators of unusually high soil fertility at these sites; some plants are state-rare or rare on the Maryland Coastal Plain.
Tuliptrees dominate the forest in most areas, and other species are at a height disadvantage. Small differences in maximum height indicate a need for the other species to occupy a niche that provides sufficient solar access to survive. On rich sites, the broad crowns of many oaks assure solar access despite the proximity of taller tuliptrees. Black walnut and sycamore benefit from windthrow openings on adjoining wetter soils. Steep slopes and southern exposures provide habitat for chestnut oaks, pines, and other species typical of a more xeric habitat. On the sandy terraces, tuliptree displays poor form and many species, including scarlet oak, are competitive. Smaller species obtain solar access in windthrow openings and along interfaces, both forest/field and forest/wetland. Large trees in swamps are unstable, and windthrow provides numerous openings for smaller species. Some species, including black locust, bigtooth aspen and black cherry, are successful in a mid-successional role following disturbance. Shade-tolerance is important to survival by certain small species and saplings of larger ones.
Despite logging in the past, many old trees still exist. The largest tuliptree has a cbh of 19 10.0; another has a trunk volume of 910 cu. ft., and three specimens exceed 150 in height. Many blackgums are quite old; the largest measures 11 2.0 cbh. Old chestnut oaks are numerous, with cbh up to 13 1.0. Other prominent specimens include numerous northern red oaks, black oaks, and American beech.
Naturalized tree species are seldom height-competitive, with white mulberry, paulownia, ailanthus and mazzard cherry being found on the more recently disturbed sites. Japanese maple, an escape, is present over about five acres and establishing well under tuliptrees, suggesting a more permanent role, similar to pawpaw and spicebush. Invasive plants were found at many sites, with English ivy, climbing euonymus, multiflora rose, cinnamon vine and Asiatic bittersweet causing serious alteration of the native forest.
While each tree species is adapted to various habitats, involving soil types, topography, hydrology and exposure, sufficient sunlight is essential; therefore, the genetic height potential of each species is inherent to its survival within those habitats. These height indexes are closely graduated, giving small survival advantages to certain species. In cool rich northeast-facing coves, the mesic dominants, by their height, exclude most of the other dominant species. The drier nature of sites having lighter soils and progressively warmer exposures limits the height of mesic dominants, allowing the sub-mesic dominants to be competitive. Heights are limited even more on well-drained terraces and upland sites with loamy sand soils and a southwest exposure, permitting the dry-mesic species to be co-dominant. Although many of the dry-mesic species exist as mid-successionals, they may be more permanent on a xeric site. Several small xeric sites, having post oak and blackjack oak on impoverished soils, exist nearby, but could not be accessed for study. The remaining species are relegated to progressively less dominant roles, according to height. Solar access is via transitional interfaces and windthrow openings, with the smallest species surviving by their shade tolerance. The total influence of these height factors dictates the structure of both the old-growth forest and the woodland disrupted by management practices.
Study by Colby B. Rucker, corrected to July 2003.