Shrub, slightly woody at the base; stems
4 to 10 dm.
high, densely tomentose and resin-dotted, with large yellow
Dry wooded slopes and rocky openings on montane coniferous
slopes of the Sierra Nevada, southeastern
and western Nevada.
Achenes 9 to 11 mm. long, tomentose, with short pappus scales.
Ray achenes three-angled; disk achenes compressed, four-angled.
Foliar with well developed cotyledons.
Pure seed definition:
PSU# 28 - Intact achene with or without pappus,
whether or not a seed is present.
ISTA: PSD #4 – Achene, with or without pappus, unless it is
obvious that no seed is present.
Samples often have a high percentage of dormant seed; in
addition to prechilling, TZ is useful in determining the
viability of ungerminated seed.
seed units per gram:
51 seeds per gram (based on AOSA pure seed units only from 5
samples received for testing from 2000 to 2005).
percent pure seed:
46 to 98%
1% to 53%
Plant material, broken seed.
400 seeds, T, 21 days @ 20°C; for fresh and dormant seed,
to main reference page)