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Eastern Deciduous Forest

The vast area covered by deciduous forests has a variety of soils, and dramatic topographic variation, from ancient mountains to foothills to gently undulating Piedmont plains. This diverse landscape hosts many plant associations. The age of the association also affects its species composition and structure. For example, the young forests growing in moist soils are composed primarily of mixed oaks, while the mature forests include beech, hemlock, maple, or basswood. Drier sites with leaner soils support associations dominated by oaks. Floodplains have a distinctive association of species that tolerate alternating cycles of flood and drought.

Living Color

The growing season in North America's deciduous forests begins and ends with an eruption of color. Spring brings one of the most dazzling wildflower displays seen anywhere in the world. As the days lengthen and the sun begins to prevail, an explosion of growth occurs, and the forest floor is transformed into a wildflower spectacle. Woodland gardeners can re-create this glorious display. But the display may be short-lived. Soon, tree buds break and the burst of leaf growth begins to cast a veil of shade on the forest floor. Many woodland wildflowers are ephemeral; they go dormant soon after blooming, as soon as their seed is ripe. This strategy evolved because when the woods become shaded and dry in summer, foliage is a liability for a small, delicate wildflower.

Ephemeral wildflowers such as spring-beauty (Claytonia virginica) and Dutchman's-breeches (Dicentra cucullaria) have underground food-storage structures such as bulbs and tubers to provide the energy needed for rapid leaf and flower development. Other wildflowers such as trillium, bloodroot (Sanguinaria canadensis), and wild geranium (Geranium maculatum) spread wide foliage to absorb summer's dim light, instead of going dormant.

Autumn in the deciduous forest is every bit as spectacular as spring. As fall approaches, the trees turn blazing shades of red, orange, and yellow. The nutrients tied up in tree leaves return to the plants below as the colorful foliage that falls to the ground begins to rot. This annual renewal also is essential for providing mulch to protect delicate crowns from drying winter winds. A successful gardener plans for autumn foliage as carefully as for spring blooms, as well as for the textural carpet of greens - ferns, mosses, and the foliage of herbaceous plants - that graces the woodland garden in summer.

Meadows

Meadows are found in breaks in the forest, created either through natural processes or at the hands of humans. Meadows form naturally through changes in the landscape, such as the silting in of beaver ponds and deposition of sand bars in river drainages. Meadows are also found on land that is too wet or too dry to support woody vegetation. Wet meadows are especially common in New England, occuring in swales along the edges of pastures or other open areas. Dry meadows and glades occur on rock outcroppings, mountain slopes, and sandy ridges. Unlike the Midwestern grasslands, a meadow is one stage in the process known as succession. It is a temporary stage in the evolution of a forest. Today, most meadows occur on abandoned agricultural land and support a mixture of native and exotic species. Unlike spring-blooming woodlands, eastern meadows slowly build up to a spectacular floral display in late summer. The late-season bloomers include grasses, asters, and goldenrods (Solidago species).

Oak/Chestnut Forest

The oak/chestnut association, which has virtually vanished from the landscape, was once dominated by an important wildlife food and timber tree, the American chestnut (Castanea dentata) . The tree has been eliminated as a major component of this forest, which is found on dry, shallow soils and sunny south- and west-facing slopes throughout the eastern half of the Eastern Deciduous Forest province. In 1930, a devastating blight was first recorded in New York, and within 30 years, the chestnut was wiped out. Today, small trees can be found resprouting from old stumps. The trees may live for twenty-five or thirty years, and a few even bear fruit. Scientists continue to search for blight-resistant strains, but the chestnut may never again dominate the canopy of this region of Eastern Deciduous Forest. In this association, the chestnut has been replaced by hickories and oaks.

Mesophytic Forest

The lush forests of the mixed mesophytic association are often referred to as cove forests, because some of the most magnificent examples grow in the cool, north-facing valleys of the Appalachian Mountains. In coves, the soils are rich, moist loams with ample humus that support a diverse mixture of massive trees, shrubs, and wildflowers. Tulip tree (Liriodendron tulipifera), beech, sugar maple, oaks, and basswood are the dominant canopy species. A wealth of flowering understory trees such as silverbells (Halesia species), magnolias, and dogwoods (Cornus species) shelter carpets of trilliums, lilies, phlox, lady-slipper orchids (Cypripedium species), and bleeding-heart (Dicentra eximia).

The western mesophytic association is a diverse forest type that occupies a transitional zone extending from the western edge of the Cumberland Plateau into the Midwestern states. On its western edge lies the oak-hickory association that forms a dynamic transition into the tallgrass prairie province. On the drier sites, oaks, maples, basswood, and other trees occur in more open-canopied stands.

Beech/Maple Forest

In moist, loamy soils of the Piedmont, northern Appalachian, and Great Lakes regions, beech and maple form dominant stands. Due to the dense shade, the diversity of the ground layer is often lower that of other forests. Evergreen wild gingers (Hexastylis, formerly Asarum, species), ferns, and sedges (Carex species) are common.

Maple/Basswood Forest

In the Midwest and western Great Lakes region, at the edge of its range, beech disappears and is replaced by basswood as a codominant with sugar maple in mesic forests. Hop hornbeam (Ostrya virginiana), pagoda dogwood (Cornus alternifolia), serviceberries (Amelanchier species), and viburnums are common understory trees and shrubs. Spring wildflowers are often common.

Oak/Hickory Forest
At the western edge of the Eastern Deciduous Forest province, precipitation drops and the forest forms a transitional zone with open woodlands and savannah. This region of drought-prone soils is dominated by oaks and hickories. Bur, black, and northern pin oak dominate. Shagbark and pignut hickory are present but seldom dominant. In the moister soils, white and northern red oak are also found. Frequent fire has created an edge of fire-tolerant trees growing amongst stands of prairie grasses. In some areas, the woodlands are confined to the moister ravines, while prairie carpets the uplands. Farther east, in the drier sites of the Piedmont plateau from Virginia south to the Gulf Coast, oaks and hickories also dominate, often in association with loblolly and pitch pines (Pinus taeda and Pinus rigida).

Floodplain Forest

The forests along streams and rivers are subject to frequent disturbance wrought by flooding. Silver maples, hackberries (Celtis species), green ash, and cottonwood abound. Before the devastation wrought by Dutch elm disease, American elm (Ulmus americana) was a dominant tree in these forests. It has been replaced by green ash.