Grindelia camporum

Grindelia camporum E. Greene
Gumplant

Family:  Asteraceae

Habit:  Perennial 5 to 12 dm. high, with several erect herbaceous stems, appearing white-varnished.

Distribution:  Found in sandy or saline bottomlands, fields, and roadsides of the San Joaquin Valley, south and central California coast, and Baja California.

Seed unit:  Achene with or without pappus.

Seed:  Achene 2 to 5 mm., angled, white to golden brown; tops generally flanged; with two to six pappus awns.

Embryo:  Foliar embryo.

Purity instructions:   Pure seed definition: 
AOSA:  PSU #28 - Intact achene with or without pappus, whether or not a seed is present.  Piece of broken achene larger than one-half of the original size, unless no seed is present.  Seed, with or without pericarp/seedcoat; 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:  In many samples, a high percentage of intact achenes are empty.  The pappus is usually not present in commercial samples.

Average pure seed units per gram:  571 seeds per gram (based on AOSA pure seed units only from 9 samples received for testing from 1999 to 2004).

Range of percent pure seed:   38% to 96%

Range of percent inert:   3% to 60%

Description of inert:  Live insects, dirt, broken seed, plant material.

Planting instructions:  400 seeds, TB, 21 days @ 15-25°C; prechill not recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 273.
Ransom Seed Laboratory

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