Alismataceae – Arrowhead Family

Aquatic monocots with flower parts in multiples of three, with green sepals and white petals. Female reproductive parts are apocarpous, meaning that flowers have many, unfused, prominent pistils that mature into small, round disks of many dry achenes. Flowers can have three, six, or multiple stamens.[1] Members of Alismataceae have basal leaves with long, parallel veins, which is characteristic of all monocots. North America is home to five genera and multiple species that all similarly produce starchy, edible roots.

 

Alisma trivale – Water Plantain

Species Code: ALTR 

Habit: Perennial, emergent, obligate wetland forb growing upright with basally erect leaves ranging from 10 to 30 cm long with single inflorescence stalk able to reach 80 to 120 cm tall. Grows from a fleshy underground corm embedded in aquatic substrate.

Leaves: Narrowly-elliptical leaves have parallel veins and long petioles all originating from the plant’s base.

Flowers: Inflorescence is a tall panicle of whorled, oppositely arranged delicate branches that end in umbel-like inflorescences or individual flowers. Each flower has three 5 mm long white petals, three alternating green sepals, a yellow center of reproductive parts, and and inferior ovary. Many stamens with six or more prominent pistils.

Fruits: Round disks of multiple dry achenes consisting of 10 to 20 individual light brown seeds.[2]

Ecology: OBL, Obligate Wetland Plant – found in vernal pools and standing water. [3] 

Notes: Corms are acrid when raw but said to be edible after careful cooking and drying.[4] the young, cooked plants are also edible. Medicinally, leaves can be applied as a stimulating poultice for bruises and swelling. Alisma roots reportedly lower cholesterol, blood pressure, as well as blood sugar levels. The powdered seed is astringent, used to stop bleeding but may cause sterility [1].

[1]Elpel, T. J., Botany in a Day: The Patterns Method of Plant Identification. HOPS Press, 2004. 155.

 

[1] Guard, J. (1995). Wetland Plants of Oregon and Washington. Lone Pine Publishing, Edmonton, Alberta.71.

[2] Pojar, J., Mackinnon, A., Editors (2004). Plants of the Pacific Northwest Coast. Lone Pine Publishing, Vancouver, Canada.  337

[3] USDA Plants Database: <https://plants.usda.gov/core/profile?symbol=ALTR7&gt;

[4] Olsen, Larry Dean. Outdoor Survival Skills. Bridgham Young University. Provo, UT. 1972.