Lasthenia californica
Lindley
Goldfields, California Lasthenia (syn. Lasthenia chrysostoma)
Family:
Asteraceae
Habit:
Simple or
freely-branched annual, less than 40 cm. tall, sometimes hairy.
Distribution: Abundant in many habitats in
California,
Arizona, Oregon and Mexico.
Seed unit:
Achene.
Seed: Achene less than 3 mm., linear to club-shaped, grabrous or hairy.
Pappus of 0 to 7 narrow awns or wider-awned scales.
Embryo: Foliar embryo.
Purity instructions:
Pure seed
definition:
AOSA: PSU# 50 - Intact achene, with or without one or more of
the following structures: beak, bristle, hairs, pappus, wing, or
firmly attached floral remnants, provided a true seed with some
degree of embryo development can be detected (either by slight
pressure or by examination over light).
Piece of broken achene larger than one-half of the original
size, unless no seed is present. Seed, with or without
pericarp/seed coat; if broken, larger than one-half the original
size.
ISTA: PSD #4 – Achene, with or without pappus, unless it is
obvious that no seed is present.
Lab notes: Obviously empty, thin and transparent achenes are
considered inert material. Use of a diaphanoscope is helpful.
Average pure seed units per gram:
8,669 seeds per gram (based on AOSA pure seed units only from
57 samples received for testing from 1994 to 2004).
Range of percent pure seed:
26 to 76%
Range of percent inert: 23 to 73%
Description of inert: Plant material, dirt, dead insects.
Planting instructions: 400 seeds, TB, 14 days @ 20°C; for fresh and
dormant seed, prechill recommended.
References:
(link
to main reference page)
Hickman, J.C., Ed. 1993. p. 299.
Ransom Seed Laboratory