Helianthemum scoparium Nutt.
Common rush-rose, Peak rush-rose
Habit: Bushy, evergreen perennial, 2 to 3 dm., with yellow flowers.
Distribution: Found on sandy flats and slopes near the coast, in closed-cone pine, woods and coastal scrub. From Mendocino to Santa Barbara County, Santa Cruz and Santa Rosa Islands.
Seed unit: Free seed.
Seed: Seeds are irregular, somewhat angled, black, cellular–papillose, 1 mm. long. Found in a loculicidal capsule 3 to 4 mm. long.
Embryo: Curved embryo with endosperm.
Purity instructions: Pure seed definition:
AOSA: PSU #1 – Seed, with or without seed coat. Piece of broken seed, with or without seed coat, larger than one-half the original size.
ISTA: PSD #10 – Seed, with or without testa. Piece of seed larger than one-half the original size, with or without testa.
Lab notes: Samples often have a high percentage of dormant seed; viability of ungerminated seeds may be determined using TZ.
Average pure seed units per gram: 2,251 seeds per gram (based on AOSA pure seed units only from 31 samples received for testing from 1993 to 2004).
Range of percent pure seed: 98 to 99%
Range of percent inert: 1%
Description of inert: Plant material, stone, dirt.
Planting instructions: 400 seeds, TB, 21 days @ 20-30°C, for fresh and dormant seed, prechill recommended.
References: (link to main reference page)
Hickman, J.C., Ed. 1993. p. 516.
Munz, P.A. and D.D. Keck. 1968. p. 173.
Ransom Seed Laboratory