Arrow-grass
General poisoning notes:
Seaside arrow-grass (Triglochin maritima) is a native plant found sporadically across Canada in saline, brackish, or fresh marshes and shores. This plant contains cyanogenic glycosides, which can release HCN during mastication by animals. Poisoning occurs primarily with ruminants, including cattle and sheep. The concentration of toxic chemicals increases during times of moisture depletion (Majak et al. 1980, Cooper and Johnson 1984, Poulton 1989).
Description
Herbs, perennial, ± robust; rhizome short, stout, clothed with sheaths of old leaves. Leaves (4-)7-30 cm × 1-4 mm. Scape erect, stout; racemes with ± densely arranged flowers. Flowers on short pedicels ca. 1 mm (2-4 mm after anthesis); perianth segments green, orbicular to ovate, ca. 1.5 mm. Carpels all fertile. Fruit ascending, not appressed to scape, oblong-ovoid, 3-5 × ca. 2 mm, base rounded. Fl. and fr. Jun-Oct. 2n = 24, 28, 36, 48, 80, 120.
Nomenclature:
Scientific Name: Triglochin maritima L.
Vernacular name(s): seaside arrow-grass
Scientific family name: Juncaginaceae
Vernacular family name: arrow-grass
Triglochin maritima L.
Geographic Information
Alberta, British Columbia, Labrador, Manitoba, New Brunswick, Northwest Territories, Nova Scotia, Ontario, Prince Edward Island, Quebec, Saskatchewan, Yukon Territory.
Toxic parts:
All parts,flowers, leaves.
Notes on Toxic plant chemicals:
Two cyanogenic glycosides, triglochinin and taxiphillin, have been found in seaside arrow-grass. The cyanogenic levels in leaves are substantially elevated during periods of severe moisture stress. Newly initiated spikes (flowering stalks) yielded high levels of glycosides. Spikes therefore pose a potential threat if they are selectively grazed. A cyanogenic glycoside content of 50 mg/100 g of green seaside arrow-grass is considered lethal, even if only 0.5% of body weight is ingested (Majak et al. 1980, Cooper and Johnson 1984).
Toxic plant chemicals:
Taxiphillin.
Taxiphillin
triglochinin
Chemical diagram(s) are courtesy of Ruth McDiarmid, Biochemistry Technician, Kamloops Range Station, Agriculture and Agri-Food Canada, Kamploops, British Columbia, Canada.
Animals/Human Poisoning:
Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.
Cattle
General symptoms of poisoning:
Convulsions, death by asphyxiation, nervousness, recumbency, trembling, vomiting.
Notes on poisoning:
Cyanide poisoning from seaside arrow-grass is similar to symptoms discussed under sheep.
Sheep
General symptoms of poisoning:
Convulsions, death by asphyxiation, nervousness, recumbency, salivation, trembling, vomiting.
Notes on poisoning:
Cyanide poisoning of sheep by seaside arrow-grass includes the following symptoms: nervousness, trembling, erratic breathing, convulsions, recumbency, and death. Postmortem findings reveal bright red blood and the smell of bitter almonds in the stomach. Treatment, if started early enough, can be successful. Intravenous injections of an aqueous solution of sodium thiosulfate have proved to be effective (Cooper and Johnson 1984).
