Home » Gardening Information » Ecology for Gardeners

Dominant Species by Plant Community

Tundra

There are two tundra associations: alpine and Arctic. The Arctic vegetation in North America is remarkably similar to that of Eurasia. The climate is so severe, and the area so new geologically, that evolution has not produced a distinctive North American Arctic flora. As the name suggests, alpine tundra is found at high mountain elevations.

Alpine Tundra

Arctic Tundra

Tundra Wetlands

Northern Coniferous Forest

The dominant species in this huge province that stretches across the northern reaches of the entire continent are cold-tolerant conifers, though mixed coniferous/deciduous stands are found in the ecotone with the deciduous forests to the south. Many wetlands dominated by either sedges or sphagnum mosses are found throughout the region.

Mixed Deciduous/Coniferous Forest

Taiga or Boreal Forest

Peatlands

Eastern Deciduous Forest

This vast province, which stretches from the Atlantic Ocean to the tallgrass prairies of the Midwest, encompasses many associations. Eastern forest associations are determined by climate, soils, and moisture. The common denominator is the dominance of deciduous canopy species. In rare instances, there are codominants that are coniferous, usually pines or hemlock. Meadows occur as scattered breaks in the forest where the soil is too wet or dry to support trees. Old-field meadows occur on abandoned agricultural land.

Maple-Basswood/Beech-Maple Forest

Mixed Mesophytic/Western Mesophytic Forest

Oak/Hickory Forest(including the former Oak/Chestnut Forest)

Floodplain Forest

The Coastal Plain of the East and Gulf coasts is a vast area with a variety of climates, soils, and moisture regimes. On rich soils, mesic forests of oaks and other hardwoods dominate, similar to forests in the Eastern Deciduous Forest province. In sandy and waterlogged soils, savannahs are found, with open pine woodlands with well-defined shrub or grassy ground layers. Bottomlands are dominated by deciduous trees interspersed with shrubs, wetland sedges, and forbs.

Northern Pine Barrens

Upland Hardwood Forest

Xeric Pine Forest

Mesic Pine Forest

Savannah and Pocosin

Bottomland Forest

Maritime Communities

Subtropical Florida

Subtropical Florida includes varied plant associations such as forested swamps dominated by canopy trees, savannah with open expanses of sawgrass as in the Everglades, islands of trees and shrubs called hammocks, and open pine woodlands on drier sites and ridges.

Savannah

Hardwood Hammock

Pineland

Swamp Forests

Mangrove Swamp

Central Prairies and Plains

Moving westward through the Central Prairie Province, rainfall diminishes and the dominant species change from tall grasses such as big bluestem to short grasses such as little bluestem and grama grasses. Composites and legumes are the dominant flowering plant families on the prairies.

Oak Savannah

Tallgrass Prairie

Mixed-grass Prairie

Shortgrass Prairie

Western Deserts

The deserts of the West are marked by limited rainfall and excessive evaporation, so drought-tolerant vegetation dominates. One plant, creosote bush, is found in all four associations of the desert province.

Great Basin

Mojave Desert

Sonoran Desert

Chihuahuan Desert

Western Coniferous Forests

Coniferous forests stretch from the Rocky Mountains to the West Coast. Except where disturbance favors aspen, conifers dominate the three major associations tied to the three major mountain ranges: the Coastal Range, the Sierras, and the Rockies.

Northwest Coastal Forest

Sierra Monatane Forest

Rocky Mountain Montane Forest

Subalpine Forest

Californian Province

In the Californian Province, winters are mild and relatively rainy. Summers are dry and hot, and much of the vegetation goes dormant as the mercury rises. Conifers, evergreen trees and shrubs with leathery leaves, bulbous plants, grasses, and annual forbs are all adapted to surviving summer drought.

California Grassland

Oak Woodland

Moist

Dry

Pinyon Juniper

Chaparral