Northwestern Sedge Carex concinnoides
Northwestern Sedge is a perennial grass native to Canada and the lower 48 states. It blooms May – Aug.
More about this plant
Carex concinnoides is a species of sedge known by the common name northwestern sedge. It is native to western North America from British Columbia to California, where it can be found in moist or dry habitat, often in woodland and forested slopes, on silty and clay soils. This sedge produces loose clumps of stems up to about 35 centimeters in maximum height from long rhizomes. The leaves are thick but narrow, sickle-shaped, and pale green in color. Inflorescences occur at the stem tips, and some pistillate inflorescences grow from nodes along the stem. The spikelets have purplish bracts. The pistillate flowers have four stigmas on each pistil, an identifying characteristic. The fruit is coated in a sac called a perigynium, which is white to light brown in color, purple-tipped, and covered in hairs. Wikipedia →
Growing & care
USDA PLANTS · TRY- Hardiness
- ≥ zone 6 derived from its U.S. range
- Lifespan
- Perennial
- Flower colour
- Yellow AI AI image-analysis of community-science photos (~87% expert agreement) — not a botanical record
Wildlife & pollinators
How pollinator value is scored →❧ Caterpillar hosts ~36 caterpillar species
Carex supports ~36 caterpillar species.
Native butterfly & moth caterpillars are the base of the terrestrial food web — most songbirds rear their young almost entirely on them. As a host for native Lepidoptera this is a strong genus.
Recorded feeding on Carex in North America, including:
+ 8 more species → ↑ show fewer
Across 205 U.S. vegetation-survey plots that recorded Northwestern Sedge, these catalog species turned up most often in the same plot — a real field co-occurrence signal, not a planting prescription.
Related plants
More Carex →
How we know this (2) Methods & honest limits
We take the plant’s U.S. county range and look up each county’s long-term climate, then summarise: native rainfall = the median annual rainfall across its counties; heat tolerance = the warm end (90th percentile) of average temperature across its range (mirroring how our cold-hardiness floor uses an extreme). Counties + medians blunt the roadside/observer bias that makes point-level climate unreliable. Needs at least five placeable counties.
Honest limits: A realized, sampling-biased niche (where it has been recorded, not its physiological optimum), and county climate is coarse — large Western counties span deserts and mountains. Derived guide, never a measured fact.
McKenzie et al. assigned each species a flower colour with a GPT-4V vision model over iNaturalist photos. We use the confident tier plus a separately-labelled lower-confidence top-up (mostly inconspicuous green/brown flowers), and render it as a small tint — never as an asserted fact, and kept out of the written synopsis.
Honest limits: AI image inference (~87% expert agreement on the confident tier); a decorative, confidence-tiered indicator, not a measured trait.
Sources for this entry (17) Open & cited
Cite this page Open data, please attribute
PlantKey’s data is open under CC BY-SA 4.0 — free to reuse and adapt, with attribution and the same licence. Photos keep their own per-image licence + credit (see Sources above).
Loading…
BibTeX
Loading…