Be on the Lookout for Amaranthus palmeri

Be aware that if you’ve used pollinator seed mixes to install pollinator habitat, make sure you don’t have issues with Amaranthus palmeri, a herbicide-resistant super weed that’s plaguing crop fields across the country. The only control is hand weeding.

Apparently, Palmer amaranth is showing up in a large number of samples of the pollinator mixes that have been used for the USDA Conservation Reserve Program Pollinator Habitat Initiative. It’s most likely the mix has been most heavily used in agricultural areas, however, if you’re seeing weeds you’re unfamiliar with, it doesn’t hurt to check plant identity.

Palmer amaranth has also made it into millet seed used for backyard bird feeders. Be aware if it shows up in residential properties. Water fowl (geese and ducks) are known to eat Palmer amaranth. Viable seed is then deposited elsewhere in their feces.

Palmer amaranth is very prolific: One plant can produce more than a million seeds. Seeds also are long lived in the soil seed bank (five years). It pays not to let plants become established at a site.

Additional links:

http://extension.missouri.edu/n/3132

https://news.illinois.edu/blog/view/6367/437988