Plant Data Sheet


Species (common name, Latin name)

Agoseris heterophylla, Annual agoseris

Image 2003, Ben Legler



Throughout the Pacific and Great Basin states, and north into British Columbia.

Climate, elevation

Dry, open areas at mid to low elevation.


Plant strategy type/successional stage



May be collected as: (seed, layered, divisions, etc.)

Fruit is an achene which ripens beginning in June. It is collected when the pappus begins to expand. Seed is tan to greyish brown in color and wind disseminated, so must be collected before it blows away. Seed maturity is indeterminant and daily collections are needed to maximize volume.


Collection restrictions or guidelines

Small amounts are rubbed to free the seed, then cleaned with an air column separator. Larger amounts can probably be threshed with a hammermill, then cleaned with air screen equipment. Agoseris grandiflora has been effectively cleaned in that manner.

Seed germination (needs dormancy breaking?)

30 days of cold, moist stratification is necessary.

Seed life (can be stored, short shelf-life, long shelf-life)


Recommended seed storage conditions

Seed is stored in paper bags or envelopes at room temperature until cleaned. Clean seed is stored in controlled conditions at 40 degrees Fahrenheit and 40% relative humidity.


Propagation recommendations (plant seeds, vegetative parts, cuttings, etc.)

Sow seed in late November or early December.


Care requirements after installed (water weekly, water once etc.)

Water deeply every other day.


Normal rate of growth or spread; lifespan

2-3 month active growth phase. 3-6 days for germination. Longer if unstratified.


Sources cited

  1. Pullman Plant Materials Center USDA-NRCS:
  2. Washington Native Plant Society, University of Washington Burke Museum:

Data compiled by Robert Franco