Echinodorus berteroi (Sprengel) Fassett
Burhead

Family:  Alismataceae

Habit:  Annual aquatic herb, with larger (8 to 30 cm.) arrowhead-shaped floating leaves and smaller (3 to 15 cm. wide) submerged leaves.  Plants often with runners.

Distribution:  Occasional in wet places at low elevation; lakes, ponds, freshwater marshes; California to southeastern U.S., South America.

Seed unit:  Achene; compressed, ribbed and tapered to a beak; occasionally free seed.

Seed:  Free seed oblong, glandular, with folded embryo.

Embryo:  Linear “U” shaped with no endosperm.

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

Lab notes:  There is often a high percentage of dormant seed in this species; a TZ test is often performed on ungerminated seed.

Average pure seed units per gram:  3,620 seeds per gram (based on AOSA pure seed units only from 8 samples received for testing from 1999 to 2004).

Range of percent pure seed:   94% to 99%

Range of percent inert:  1% to 5%

Description of inert:  Plant material.  

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