Verbena, Western vervain
Perennial 35 to 80 cm., much-branched. Inflorescence in
terminal spikes of blue to purple flowers.
Found in dry to moist places below 8000 feet, in many plant
communities in cismontane California north to Oregon and
south to Baja California.
Nutlet, usually single, but sometimes up to four fused
Nutlet 1 to 2 mm., compressed-oblong and slightly
rounded-triangular in cross section, making it somewhat
two-sided; the rounded back bearing lengthwise ridges toward
lower end and a network of cross ridges above; inner face of
two planes meeting in a low ridge, the surface generally
covered with whitish papillae; margin bordered by a narrow
flange; attachment scar whitish.
A foliar embryo in woody seed coat, endosperm lacking.
Pure seed definition:
AOSA: PSU #10 – Intact nutlet, whether or not a seed is
present. Piece of broken nutlet larger than one-half of the
original size, unless no seed is present. Seed, with or
without seed coat. Piece of broken seed, with or without
seed coat, larger than one-half the original size.
ISTA: PSD #18 - Nutlet, unless it is obvious that no seed
is present. Piece of nutlet larger than one-half the
original size, unless it is obvious that no seed is
present. Seed, with the pericarp/testa partially or
entirely removed. Piece of seed larger than one-half the
original size, with the pericarp/testa partially or entirely
Often samples contain multiple seed units.
pure seed units per gram:
2,418 seeds per gram (based on AOSA pure seed units only
from 18 samples received for testing from 1997 to 2004).
percent pure seed:
91 to 98%
1 – 8%
Description of inert:
Plant material, dirt
400 seeds, TB, 18 days @ 15 to 25°C; for fresh and dormant
seed, GA3 recommended @ 15°C.
to main reference page)
J.C., Ed. 1993. p. 1088.
Martin, A.C. and W.D. Barkley. 1961. p. 194.
Munz, P.A. and D.D. Keck. 1968. p. 687.