Sulphur Buckwheat Eriogonum umbellatum (Su,D,RS,N)
A colorado native
- Full sun
- Rocky slopes, shallow sandy soils
- Moisture: Dry
- Host Plant to lupine blue butterfly
Sulphur-flower buckwheat is a native, low-growing, woody perennial in the buckwheat family (Polygonaceae). The plant typically forms low, broad mats with individual clumps ranging from 4 inches to 2 ft (but up to 4 ft) tall and wide. Leaves are basal, 1 inch long, and softly wooly or hairless. Flower stems are 3 to 16 inches tall and topped by umbel-shaped clusters of tiny flowers. Flowers range from sulfur yellow to orange or reddish, sometimes turning rusty orange-red with age. Floral displays can color entire slopes starting in June at lower elevations and continue into September or October at higher elevations.
Propagation by direct seed
Seeds need 3 months cold, moist stratification to germinate, and may be longer depending on where it was collected. Seed rates are 8 -10 pounds an acre.
Role in Ecosystem
Pollinators: Sulphur-flower buckwheat attracts a wide variety of bees and other native pollinators.
Larval host and nectar source for lupine blue butterfly (Plebejus lupini). The cythera metalmark butterfly (Apodemia mormo cythera) and the Rocky Mountain dotted-blue (Euphilotes ancilla) are also found in association with a few varieties of sulphur-flower. Bees produce a strong, dark honey from the nectar.
The seeds are an important food source for many species of birds and small mammals. Quail, sage-grouse, deer and mountain sheep eat the leaves, and insects found on the plants are an important food source for sage-grouse chicks.