Eleocharis macrostachya Britton
Spikerush

Family:  Cyperaceae

Habit:  Perennial, with rhizomes, stems 5 to 10 dm., 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.