Ask Mr. Smarty Plants

Since this plant is found in far northern Alaska and Canada, it is not likely to show up in Travis or Williamson Counties; plus, you did not give us a valid e-mail address so this probably will not get back to you anyway, but we try to give all questions as much of an answer as we can.

One souce we consulted (Wikipedia) said: "Hedysarum (Sweetvetch) is a genus of the botanical family Fabaceae, consisting of about 309 species of annual or perennial herbs in Asia, Europe, North Africa, and North America." This article also said it needed documentation, which we believe to be true. As a member of the Fabaceae (pea) family, it is related to the bluebonnet, and pictures we found of the bloom somewhat resembled the iconic Texas wildflower.

However, further research on our part found several articles recounting Native Americans' use of the plant in Alaska and Canada. The plant does not appear in our Native Plant Database nor in the USDA Plants website, which is the basis for our information. Here are some links to sites we found with more information:

From wikispaces.com Hedysarum mackenzii vs. Hedysarum alpinum

From the Ethnobotany Journal: Is Hedysarum mackenziei (yes, that's how they spelled it) (Wild Sweet Pea) actually toxic?

From the Circle District Historical Society of Central Alaska Hedysarum mackenzii.

Your question was "What is the effect of Hedysarum mackenzii?  Since the experts don't seem to be able to agree on whether it is poisonous or not, we really don't know. We do feel relatively sure you are not likely to stumble on it in Central Texas.