Eleocharis macrostachya

Eleocharis macrostachya Britton
Spikerush

Family:  Cyperaceae

Habit:  Perennial, with rhizomes, stems 5 to 10dm., purplish at base becoming straw-colored above.

Distribution:  Found in marshes, pond margins, vernal pools, and ditches.  Widespread in montane, temperate regions in California and throughout the Western Hemisphere.

Seed unit:  Achene.

Seed:    Achene triangular, strongly flattened, yellowish-brown, 1.5 to 2.5 mm.; tubercle (cap) is more or less conic.  Perianth bristles unequal.

Embryo:  Linear basal embryo.

Purity instructions:   Pure seed definition: 
AOSA:  PSU #29 – Intact achene, with or without perianth, 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/seed coat; if broken, larger than one-half the original size.

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:  2,373 seeds per gram (based on AOSA pure seed units only from 17 samples received for testing from 1995 to 2004).               

Range of percent pure seed:   79 to 99%

Range of percent inert:  1 to 13%

Description of inert:   Plant material, broken seed, dirt.

Planting instructions:  400 seeds, TB, 21 days @ 20-35°C; prechill not recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 1142.
Martin, A.C. and W.D. Barkley. 1961. p. 136.
Ransom Seed Laboratory

Cyperus eragrostis

Cyperus eragrostis Lam.
Nutsedge 

Family:  Cyperaceae

Habit:  Perennial with short, thick rhizomes, coarse fibrous roots, and triangular stems; 10 to 90 cm. tall.

Distribution:  Common in vernal pools, stream banks, and ditches of California, Oregon, and temperate South America.

Seed unit:  Achene.

Seed:  Achene three-sided, 1.2 to 1.4 mm., stalked, finely reticulate, black to brown; tip beaked.  Some achenes are still enclosed in straw-colored, ovate, three-nerved scales.  Achenes should be removed from pieces of plant material and the scale for the AOSA pure seed definition.

Embryo:  Basal.

Purity instructions:   Pure seed definition: 
AOSA: PSU #28 – Intact achene, whether or not a seed is present, with or without beak.   Piece of broken achene larger than one-half of the original size, unless no seed is present.

Lab notes:  In some samples, low germination may be due to the presence of empty achenes.  When a sample is received that appears unmilled; immature, light colored, “obviously empty” achenes could be removed and categorized as inert matter.  It is recommended that this be communicated on the final data sheet as the removal of immature achenes will alter the final viability results.

Average pure seed units per gram:  8,705 seeds per gram (based on AOSA pure seed units only from 8 samples received for testing from 1994 to 2003).

Range of percent pure seed:  44% to 99%

Range of percent inert:  1% to 55%

Description of inert:  Plant material.

Planting instructions:  400 seeds, TB, 21 days @ 20-35°C; for fresh and dormant seed, prechill recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 1139.
Martin, A.C. and W.D. Barkley.  1961.  p.  136.
Munz, P.A. and D.D. Keck.  1968.  p. 1425.
Ransom Seed Laboratory

Carex obnupta

Carex obnupta L. Bailey
Slough sedge

Family:  Cyperaceae

Habit:  Forming beds and dense raised clumps from rhizomes, 3 to 15 dm. long.

Distribution:  Central western California and San Francisco Bay area, north to British Columbia in marshes and wet meadows.

Seed unit:  Achene, purplish-black with lighter center and narrow hyaline margins.

Seed:  Achene hard, lenticular, ovoid, completely surrounded by smooth or toothed perigynium.

Embryo:  Embryo is basal extending less than half the length of the seed in starchy endosperm.

Purity instructions:  Pure seed definition:
AOSA: PSU#27 - Intact achene whether or not a seed is present. Piece of broken achene larger than one-half of the original size, unless no seed is present.

Average pure seed units per gram:  1,203 seeds per gram (based on AOSA pure seed units only from 2 samples received for testing from 2001 to 2002). 

Range of percent pure seed:  99%

Range of percent inert:  1%

Description of inert:  Plant material.

Planting instructions:  400 seeds, TB, 21 days @ 20-35°C; prechill not recommended.

References:  (link to main reference page)
Hickman, J.C., Ed.  1993.  p. 1131.
Munz, P.A. and D.D. Keck.  1968.  p. 1461.
Ransom Seed Laboratory