The University of Minnesota Extension Service had a lot of farmers stop by their booth at the MN Ag Expo to look at the weeds they had growing. All the weeds were in the pigweed family. There was regular pig weed, waterhemp and the large one on the left side of the picture, palmer amaranth. Notice how much bigger the palmer amaranth is compared to the other weeds. We struggle in Minnesota to control waterhemp. Palmer amaranth is described as waterhemp on steroids!

Palmer amaranth got established in the southern United States and has spread as far as northern Iowa. That is getting too close to my farm for comfort! Palmer amaranth has been found twice already in Minnesota. In both cases it was contaminated conservation seed. The Minnesota Department of Agriculture was in those fields with flame throwers to try and make sure all the weeds were destroyed and did not go to seed. The fields were inspected in the following years to make sure there were no palmer amaranth weeds growing.

Palmer amaranth looks very much like waterhemp. However there are two ways it is different. First it grows much faster than waterhemp and gets taller. The second distinction is the leaf petiole is much longer. That means from the stalk of the plant, the petiole or stem to the leaf is much longer than waterhemp. This summer if you see a weed you suspect may be palmer amaranth have your agronomist check it out or contact the Minnesota Department of Agriculture.