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Plant Identification: White Snakeroot
Plant Identification: White Snakeroot
Over the years, I have received many pictures of problem lawns and landscape plants. Most of them I am able to identify, but occasionally, I am stumped. That is when I go to a network of professionals and colleagues to help me identify or diagnose what may be the cause of the problem or identify the plant. I recently needed to go to my plant identification "helper" list to help me identify a weed that I didn't even know existed.
Kenny Gute, franchise manager from our Boone, Iowa franchise likes to send me pictures of diseases, insects and other flora and fauna that he comes across in his daily work. The last one he sent me was a real puzzler and I had no idea what the plant was or how he could treat it.
I first sent a picture of the weed to a colleague, Scott Wanzor, from PBI Gordon, a company that specializes in the manufacture of weed control products. He did not know what the weed was, so he sent it to Dr. Bert McCarty at Clemson University. Dr. McCarty is a well-known weed scientist in the Southeastern US, but has never been to Iowa, so he didn't know what it was.
Even though he did not know, one of his grad students was able to ID it as white snakeroot, Ageratina altissima. Pretty cool! In the meantime, another colleague from PBI Gordon, who was copied on the e-mail, Dr. Gary Custis, confirmed the identity of the weed. He responded that he has seen it before, but didn't know what it was called. He did know, as a beekeeper, that he needed to keep his bees away from the plants when they are in bloom because when bees go to the flowers his honey becomes bitter. Bees don't mind it, but people cannot consume the honey.
Wow! That sounded ominous, so I looked up the weed to learn more about it. White snakeroot is a native plant and can grow as high as three feet. Leaves and stems of the plant contain tremetol, which is extremely poisonous. If it is consumed by cows in a large enough amount, the animal can develop a condition known as "trembles." If humans drink the milk of cows that have ingested a large quantity of white snakeroot, they can develop a condition known as "milk sickness" and it can be fatal. It is said that Abraham Lincoln's mother died of "milk sickness."
Fortunately, it can be controlled with many different weed prevention products. If there are just a few plants, they can be hand-pulled. Wait until after a good rain when the ground is soft. The best time to do this is in late summer when the plant is in bloom and more easily identified. Wear gloves to be on the safe side.