Tetradymia glabrata

Tetradymia glabrata Torrey and A. Gray
Bald-leaved feltthorn

Family:  Asteraceae

Habit:  Shrub 3 to 9 dm. high; branched, tomentose, with glabrate leaves.  

Distribution:  Dry scrub and Joshua tree woodland of the Great Basin and the Mojave Desert in California, Oregon, Idaho and Utah.

Seed unit:  Achene.

Seed:  Achene 3 to 5 mm., with short, stiff hairs; ribs glandular; pappus of many fine bristles 6 to 8 mm. long.

Embryo:  Foliar with well-developed cotyledons, no endosperm.

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.

Average pure seed units per gram:  529 seeds per gram (based on AOSA pure seed units only from 1 sample received for testing in 2002).

Range of percent pure seed:  30%

Range of percent inert:  69%

Description of inert:  Broken seed, plant material.

Planting instructions:   400 seeds, TB, 21 days @ 20°C; for fresh and dormant seed, prechill recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 352. 
Munz, P.A. and D.D. Keck.  1968.  p. 1256.  
Ransom Seed Laboratory

Tetradymia-glab-intact-no-s.jpg
Cirsium-scar-seed-present.jpg