You are here

Vegetation

Coastal Forest and Prairie Habitats

Upland Forest

Upland Forest (Overleaf Lodge)

Upland Forest

An upland (as opposed to riparian or bottomland) forest along Oregon's Coast has a closed canopy dominated by Douglas-fir and bigleaf maple. The forest has usually been logged and the current tree cover is second or third growth.

The thick and varied forest canopy catches rain and collects dew. Tree roots hold the soil of steep slopes in place, and shelter mosses, lichens and other understory vegetation. Branches shade and cool upland streams essential to native fish -- including salmon. Upland forests provide habitat for hundreds of species of birds, mammals and reptiles and amphibians -- many of which will only live in this type of forest.

Coastal and Lowland Prairie

The coastal prairie is sporadic pockets of grasslands that are usually absent of trees and shrubs. Seasonal seeps often hydrate the soil to saturation in winter and gradually dry out in summer. These areas are commonly impacted by wind and/or salt spray.

Historically, most of the native plants of the coastal prairie were classified into one of two types of perennial grasses: bunch and sod-forming. Bunch grasses are extremely long lived and increase in size each year. They have an extensive root system that burrows deep into the soil and naturally prevents erosion. The parent plant produces and spreads an abundance of seeds. In contrast, the sod-forming grasses tend to propagate vegetatively and reproduce by sprouting from a root-like structure. The conversion of coastal prairie to agricultural land has created a suitable habitat for annual grasses, and has become the single greatest threat to native perennial grasses.

The characteristic plants that are associated with coastal prairie include hairgrass (Deschampsia caespitosa), fescue (Festuca spp.), western bracken fern (Pteridium aquilinum var. pubescens), sedges (Carex spp.), bluedicks (Dichelostemma capitatum), California blue-eyed grass (Sisyrinchium californicum), lupine (Lupinus), checkerbloom (Sidalcea spp.), and footsteps-of-spring (Sanicula arctopoides).

Bottomland Forest

Bottomland Forest

Bottomland Forest
(Oregon Guides And Packers)

Bottomland forest is comprised of both hardwood and softwood tree species that occur on floodplains or seasonally wet areas. Historically, the term bottomland hardwood forest has been used to describe forests that occur on river floodplains. The current definition (Huffman and Forsythe 1981) includes the following:

  1. The habitat is inundated or saturated by surface or groundwater periodically during the growing season
  2. The soils within the root zone become saturated periodically during the growing season
  3. The prevalent woody plant species associated with this habitat have demonstrated the ability, because of morphological and/or physiological adaptations, to survive, achieve maturity, and reproduce where the soils within the root zone may become anaerobic for various periods during the growing season

In the Oregon Coast Range these forests are usually dominated by red alder, Oregon ash, and willow as well as several species of shrubs (e.g., cascara, Douglas hawthorn, Pacific ninebark). Other common plants include creek dogwood, ninebark, Indian plum, vine maple, hazelnut, stinging nettle, and sedges.

Sources

Huffman, R. T., and Forsythe, S. W. (1981). Bottomland hardwood forest communities and their relation to anaerobic soil conditions. Wetlands of bottomland hardwood forests. J. R. Clark and J. Benforado, eds., Elsevier, Amsterdam, 187-196.

A Place for Nature. Willamette Basin Habitat Conservation Priorities.. Defenders of Wildlife. PDF. 20pgs.

Compiled by John Ame, Science Writer (2007)