Seaside Arrowgrass
Triglochin maritima

Family: Arrowgrass (Juncaginaceae)
AKA: Common Arrowgrass
Photo taken on: July 27, 2020
Location: Almont, GV, CO
Life Zones: Plains to foothills
Habitat: Mountain marshes and wet alkaline meadows

Flowering stalk grows to over 3 feet tall from basal grass-like leaves. Spikes of tiny, globular, greenish-purplish flowers with a tuft of white stigmas grow in a dense spike at the upper part of the stalk (photo below left). Fruits are cylindrical (photo below right). It cannot grow in the shade.

Flora of North America reference.

Marsh Arrowgrass
Triglochin palustris

Family: Arrowgrass (Juncaginaceae)
AKA: Slender Arrowgrass
Photo taken on: July 7, 2021
Location: Russell Lakes State Wildlife Area, SLV, CO
Life Zones: Plains to subalpine
Habitat: Moist, alkaline meadows and marshes

Flowering stalk grows to 2 feet tall from basal grass-like leaves. Spikes of tiny, globular flowers grow at the upper part of the stalk, not as densely as T. maritima above. Fruits are narrow and winged. Not as robust or as common a plant as T. maritima.

Flora of North America reference.