Taisha is the writer for today's entry:
Today's photographs are of Anticlea elegans (syn. Zigadenus elegans), or the mountain death camas. It is another one of the flowering plants featured in Jim Pojar and Andy MacKinnon's Alpine Plants of British Columbia, Alberta, and Northwest North America. These photographs are courtesy of contributing photographers Linda Kershaw and Judith Holm. Thanks Linda and Judith!
Anticlea elegans is widely distributed in Canada and the USA, and also occurs in northern Mexico. Elevations where mountain death camas can be found range from 0 to 3600m (nearly 12000 feet); habitats include moist grasslands, open forests, river and lake shores, and even bogs in coniferous forests. It is a bulbous species that grows 15-50cm tall. The narrow glaucous leaves are gathered mostly near the base, and become bract-like upward on the stem. Upon the stem sit several to many bowl-like flowers with greenish-white to cream-coloured tepals, each with a large bilobed green gland toward the base. The three-lobed fruits--capsules--are egg shaped and carry numerous seeds. For photographs of mountain death camas throughout its life cycle, see Alaska Wildflowers: Anticlea elegans.
As the common name would imply, all parts of this plant are poisonous. Zigadenus and closely related genera such as Anticlea and Toxicoscordion, contain toxic steroidal alkaloids such as zygacine and zygadenine. In a comment from a previous entry on Toxicoscordion venenosum, a subscriber to the Botany Photo of the Day asked how these toxins work. As it turns out, I have some knowledge of human physiology, partly from taking a physiology course over the summer. These alkaloids cause a rapid increase in the permeability of voltage-sensitive sodium channels in excitable cell membranes. Excitable cells are cells that have a difference in the voltage across the membrane (membrane potential), allowing for electrical signals to be transmitted for communication. In this case, it would be the neurons and the muscle fibres (cells) of the heart. The rapid increase in intracellular sodium results in a loss of membrane potential. Then, the loss of electrical communication between nerves and muscle fibres results in cardiac arrhythmia. It is also thought that
Symptoms of Anticlea poisoning usually occur within 30 minutes to four hours, and generally resolve within 24-48 hours, although they may persist for days. Poisoning from Anticlea and its relatives is usually characterized by headache, diaphoresis, salivation, nausea, vomiting, diarrhea, abdominal pain, hypotension, bradycardia, and shock. Syncope, respiratory depression, scotomata, paresthesias, fasciculations, muscle spasticity, hyperreflexia, vertigo, ataxia, dizziness, coma, seizures, and death may also occur. (see: Auerbach's Wilderness Medicine (6th ed, in 2011).