Juncaginaceae

Arrowgrass Family

Seaside Arrowgrass

FAMILY: Arrowgrass family (Juncaginaceae) – Triglochin genus.

SPECIES: Seaside arrowgrass (Triglochin maritima L.).

TO UTILIZE AS FOOD: Warning! Although the leaf bases and seeds of seaside arrowgrass are reported to be edible, these parts must be thoroughly boiled to eliminate poisonous compounds called cyanogenic glycosides (triglochinin and taxiphillin). Arrowgrasses are dangerous to cattle. The colonies located for this reference were too small to harvest and failed to produce enough seeds for a meaningful evaluation.

IDENTIFICATION: The Triglochin genus is currently represented by 5 species in the United States, of which only 2 occur in the Southwest. Fruits, stigmas, and structures on the leaves called ligules are helpful for identification. Ligules are small appendages arising from where the leaf blades meet the leaf sheaths. Red arrowgrass (T. coccinea) is the other southwestern species, easily distinguished by its 3-carpellate pistils, 3 stigmas, and 3-segmented linear fruits.

Description of seaside arrowgrass (Triglochin maritima): FORM stemless, perennial, grass-like plant about 3-11 dm tall emerging from a rhizome; LEAVES simple; arranged basally; blades long-linear and rounded in cross section; sheaths thin; ligules 1-5 mm long, often hood-like, entire, or shallowly lobed; FLOWERS small, perfect, and arranged in spike-like racemes terminating long scapes; bracts absent; perianth parts 6, arranged in 2 series of 3 representing sepals and petals, yellowish-green to purplish; pistils 1, compound, with 6 carpels; styles absent; stigmas 6, head-like or feathery, often white or pinkish-purple; stamens 6; FRUITS follicles oblong to ovoid-angled, about 4-6 mm long, rounded at the bases (rather than tapered), and separating into 6 segments, each with 1 seed; SEEDS fusiform, flat, or angled; HABITAT meadows and marshy areas; tolerant of alkali, widespread throughout the western and northern United States; blooming May to August.

REFERENCES: Seaside arrowgrass (Triglochin maritima): leaf bases Turner (2009-b p. 312); seeds Blankenship (p. 25), Chamberlin (p. 383), and Moerman (p. 258).