Palmer amaranth, also infamously called Palmer pigweed, is well-known for its aggressive growth and can often seem overwhelming to farmers. But with a zero-tolerance policy against weeds, you can turn the odds in your favor.1,2
Native to the southwestern U.S., Palmer amaranth is now found in 39 of the 48 continental U.S. states.3
In soybeans, Palmer amaranth can create yield losses of up to 79%.2,4
Often confused with similar weeds, plants can grow 2-3 inches per day. Leaves are diamond- to egg-shaped and often have a symmetrical leaf arrangement with a poinsettia-like appearance.2,5
Uncontrolled plants can reach 10 feet, and no other pigweed species has terminal panicles that can reach 1-1/2 feet long.6
A single plant can produce up to 1 million seeds and be responsible for generations of weeds in the same growing season.1,7
Palmer amaranth plants germinate from early spring all the way through the first killing frost, which means multiple products with multiple sites of action are needed to prevent weeds from getting big enough to produce. Palmer amaranth has rapidly gained a foothold in the U.S., and it is important to develop a weed management strategy to help prevent it from spreading.1,3
to diversify herbicide programs and weed control strategies.
with a burndown herbicide or tillage.
using a residual product within 2 weeks before planting or prior to crop emergence.
before weeds grow taller than 4 inches.
If weeds escape, use tillage or physically remove them before plants produce seed.
1 Crop Science (Sep. 10, 2019). Zero Tolerance Weed Control of Waterhemp/Palmer Amaranth. Retrieved from http://www.cropscirnce.bayer.us
2 United States Department of Agriculture (Sep. 10, 2019). Palmer Amaranth. Retrieved from http://www.fsa.usda.gov
3 Crop Science (Sep. 10, 2019). Palmer Amaranth on the Move in the Midwest. Retrieved from http://www.cropscience.bayer.us
4 Legleiter, T., Johnson, B. Purdue University — Purdue Extension (Nov. 2013). Palmer Amaranth Biology, Identification, and Management. Retrieved from http://www.extension.purdue.edu
5 Crop Science (Sep. 12, 2019). How to tackle waterhemp. Retrieved from http://www.cropscience.bayer.us
6 University of Missouri Division of Plant Sciences (Sep 10, 2019). Weed ID Guide, Palmer Amaranth. Retrieved from http://www.weedid.missouri.edu
7 Sosnoskie, L., Culpepper, S., Kichler, J., Webster, T., University of Georgia Extension (Feb. 1, 2014). The biology and ecology of palmer amaranth: Implications for control. Retrieved from http://www.extension.uga.edu