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Saturday - October 29, 2011

From: Kalama , WA
Region: Northwest
Topic: User Comments, Seeds and Seeding, Poisonous Plants, Herbs/Forbs
Title: Comment on poisonous sweet pea plant from Kalama WA
Answered by: Barbara Medford

QUESTION:

No question, comment only. I am aware of the story of Christopher McCandless (Call of the Wild)and the belief that he was poisoned by ingesting part of the sweet pea plant; however I am curious what part of the plant.I have eaten the blossoms for years, enough at a time to make a salad. They are delicious and i have NEVER had any adverse health effects. I am very healthy and age 45. An old Asian lady showed me to gather them and eat the young blossoms before they open . .she said the are called "mountain vegetable" (loose translation). In the book by Marjorie Harris, Botanica North America, Page 269, it states that after the "Alaskan incident", Edward Treadwell, a graduate chemistry student from the Univ. of Alaska tested the seeds of both H. Mackenzii and H. Alpinium to see if the seeds were poisonous. Treadwell found no evidence of poison. I know many people who eat the wild sweet pea blossoms (mostly the pink-purple and white). The book states the jury is still out. Maybe further research is needed.

ANSWER:

While we appreciate your comments, we are not a forum, but are set up to answer questions and recommend native plants to gardeners. We did look into this a little, and found there are 16 members of the genus Lathyrus, with several variations of the common name "sweet pea." All are members of the Fabiaceae, or pea, family. Seven of these are native to Washington and the one we chose as an example is Lathyrus palustris (Marsh pea).

These comments are on the webpage you will reach by following the plant link:

"Use Food: EDIBLE PARTS: Peas and very young pods. Collect young pods in early summer and peas slightly later. Do not wash with detergent or sanitizer, only water. (Poisonous Plants of N.C.)
Warning: POISONOUS PARTS: Seeds. Toxic if ingested in large quantities. Symptoms include Lathyrism: paralysis, slow and weak pulse, shallow breathing, convulsions. Toxic Principle: Amine, phenol, and glycoside. (Poisonous Plants of N.C.)"

This does not mention the flowers, but if you removed them from the plant and ate them before the seeds developed, there is no reason for them to be poisonous. Frankly, since childen are smaller and more susceptible to substances, we would not offer them to a child. And, if the gentleman you mentioned cooked up a large batch of the more mature seed pods and/or seeds, he very well could have suffered ill effects.

From the Image Gallery

Marsh pea
Lathyrus palustris