This section is from the book "A Guide To The Poisonous Plants And Weed Seeds Of Canada And The Northern United States", by Robert Boyd Thomson, H. B. Sifton. Also available from Amazon: A guide to the poisonous plants and weed seeds of Canada and the northern United States.
This form is more common in the west, growing in valleys among the mountains, and is stated to have caused the death of cattle and horses. It resembles the former species except that the flowers are whitish and in a looser panicle with long, narrow flower parts.
It produces effects similar to those of Veratrum viride and the treatment is the same. Chesnut and Wilcox have proved that a solution of potassium permanganate and aluminium sulphate, similar to that used for Zygadenus poisoning, forms a chemical antidote, neutralizing the poison not already absorbed.
*For another antidote look under Veratrum californicum.