Field Guide to Plants Poisonous to Livestock: Western U.S.
Common name: Seaside arrowgrass
Habitat: Meadows, damp areas, marshes, low to moderate elevations
Toxic season: Year-round
Features: With flower stalks, may be up to 3' tall. Leaves grow in a bunch at the base, are somewhat grass-like, but fleshy and round except for a semi-circular indentation extending the length of the "blade" on one side. Flowers small, green densely and closely attached along upper half of flower stalks, giving stalks a knobby appearance. Fruits are 6-part, roundish pods, each segment containing one seed; pods cluster tightly along stalk.
Poison type: Cyanogenic glycoside
Signs/effects: Excitement followed by depression, rapid/labored breathing, bright red blood, excessive salivation, muscle twitching, incoordination, convulsions, bloat, coma, death. Death may occur within an hour after eating large quantities.
Treatment: Sodium thiosulfate and sodium nitrate IV can be effective if administered soon after toxic amount is ingested, but proper dosage is critical and requires veterinary evaluation. Death may occur too rapidly for treatment to be administered.
Comments: All parts toxic when stressed by frost or drought, esp. leaves and seeds. Ruminants are more susceptible than non-ruminants, but horses have been poisoned.
© Copyright 1998 by Shirley A. Weathers