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Wetlands and Meadows

Eagle Ridge Fen

Eagle Ridge Fen. View other habitats.

Wetlands comprise a relatively small portion of the watershed (approximately one percent). They include perennially saturated fens and bogs, seasonally saturated mountain meadows, and sedge-willow complexes on lake deltas.

Lower Watershed

Small patches of non-forested habitat—including wetlands—break the nearly uniform canopy of second-growth conifer forest in the lower watershed. (See Map of Lower Cedar River Watershed (pdf))

Major wetland habitats in the lower watershed include beaver-pond, shrub, and bog/fen complexes. An extensive beaver-pond system is found at the headwaters of Williams Creek, along the northern boundary of the lower watershed.

There is also a larger, more complex wetland system surrounding and east of Walsh Lake. The Walsh Lake complex includes:

  • notable submerged aquatic plant communities
  • emergent wetlands dominated by tule (Schoenoplectus acutus)
  • shrub wetlands dominated by hardhack (Spiraea douglasii).

Extensive forested wetland habitats are found along middle Rock Creek and include beaver ponds and unusual forested fens dominated by:

  • Sitka spruce (Picea sitchensis)
  • western hemlock (Tsuga heterophylla)
  • sphagnum moss (Sphagnum species)

There is also a small sphagnum bog in the lower watershed near the Rock Creek wetland complex, which supports characteristic bog plant species such as:

  • Labrador-tea (Ledum groenlandicum)
  • western bog-laurel (Kalmia microphylla)

Upper Watershed

Wetland habitats in the upper watershed vary widely in size and are distributed from the valley bottom of the Cedar River (1,550 feet elevation) to the higher ridges (over 5,000 feet elevation). The water source of these wetlands varies and includes surface water from streams and lakes, snowmelt, and groundwater.

River Deltas

Extensive sedge meadows (Carex vesicaria and other species) and willow stands (predominantly Sitka willow, Salix sitchensis) are present on the deltas formed by the Cedar and Rex rivers as they flow into Chester Morse Lake. (See Map of Upper Cedar River Watershed (pdf))

Another small delta plant community exists at the mouth of Bridge Creek on the north side of Chester Morse Lake. These delta plant communities have been changing in recent decades, as water levels in the lake have been managed at higher levels than in the past.

Fens and Bogs

Two of the watershed’s most unusual wetlands occur south of Little Mountain. These wetlands share both fen (neutral pH and nutrient rich) and bog (low pH [acidic] and nutrient poor) characteristics. A globally rare beetle—Bellers ground beetle (Agonum belleri)—has been documented in these fen/bog wetlands. They support a wide variety of unusual sedge, grass, and forb plant species, including:

  • a large population of sweet gale (Myrica gale)
  • white beakrush (Rhynchospora alba)
  • two carnivorous plant species: sundew (Drosera rotundifolia) and bladderwort (Utricularia species)

There are also several smaller sphagnum bogs at higher elevations in the upper watershed.

Pond and Lake Margins

Shorelines around small lakes, ponds, and tarns often include wetland margins that have formed as shallow areas fill in with sediment and organic material.

These fringes of wetland vegetation are often dominated by:

  • shootingstars (Dodecatheon jeffreyi)
  • grasses
  • sedges (Carex species, including the rare russet sedge, C. saxatilis)

Headwater Basins

Headwater basins usually support abundant streams and wet meadows with diverse grass, sedge, and forb communities (for example, in the headwater basins of Lost, Boulder, and Lindsay creeks and the Rex River).

There is an expansive wet meadow complex in the upper Rex River basin, much of which is surrounded by old-growth forest.

Higher elevation wetland meadows may be at risk due to predicted climate change effects. Projected warmer winters and drier summers will likely result in reduced snowpack, earlier snowmelt, and higher summer evapotranspiration rates that could result in loss of wetland characteristics and invasion by trees.

Dry Meadows

Upland shrub-forb meadows are located on the south-facing slopes of Mount Baldy and Tinkham Peak at the northeast boundary of the watershed. This habitat is unique in the watershed and likely owes its origin to shallow and steep soils, a desiccating south exposure, and a short growing season.

Habitat types in the watershed: