General Species Description
- This plant has clustered spongy, rounded triangular stems growing from rhizomes. The stems are triangular, and very leafy. Scirpus microcarpus often grows to be about 1.5m tall.
Leaves
- The yellow-green leaves grow both basally and up the stem. They are flat, 10-15mm wide, with rough margins, and leaf sheaths that have a purplish tinge.
Inflorescence/Flowers
- Inflorescence of small-flowered bulrushes arises from a single point into numerous short (3-8mm long) spikelets. The involucral bracts of the flowers are unequal in length and leaf-like. Blooms from June to August.
Fruits
- The fruits are tiny (1mm long) ovate achenes surrounded by 4-6 slightly longer bristles. The scales of which have a black midstripe that extends past the awn.
Habitat
- This species is intolerant to shade, and is found in wet to inundated, nitrogen rich soils. Found to grow well in disturbed sites. This plant commonly grows with skunk cabbage (Lisichiton americanum), soft rush (Juncus effusus), and a variety of willow species such as scouler willow (Salix scouleriana), and sitka willow (Salix sitchensis).
Range
- Found throughout western North America, and Asia. This species grows in all counties in our area.
Similar Species
- Can be confused with Scirpus atrocinctus, which has less robust round stems that are somewhat woody. Scirpu. atrocinctus also has 6 bristles that are up to 5 times in length. When Carex obnupta is not in flower it can look similar, but lacks spongy stems and has leaves that are green and attached to the base.
Ecological Value
- Considered a valuable food and nesting material source for animals.
Human Value
- The leaves were laid over and under food in steaming pits, and also used to weave light duty baskets by the Native peoples of the Pacific Northwest.
References
- Cooke, Sarah. 1997. Wetland Plants of Western Washington and Northwestern Oregon. Seattle Audubon Society, Seattle, Washington.
Gilkry, H.M., L.J. Dennis. 1967. Handbook of Northwestern Plants. Oregon State University Bookstores, Corvalis, Oregon.
Pojar, J, and A. Mckinnon. 1194. Plants of the Pacific Northwest Coast. B.C. Ministry of Forests and Lone Pine Publishing.
This page was created by: Aaron Nepple, August 2000
Return to Northwest Oregon Wetland Plants Project