Helianthemum scoparium

Helianthemum scoparium Nutt.
Common rush-rose, Peak rush-rose

Family:  Cistaceae

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

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