Palmer Amaranth

Pollen-Mediated Gene Flow and Transfer of Herbicide-Resistant Alleles January 22, 2019

Pollen-mediated gene flow at a distance could allow the spread of rare herbicide-resistant alleles and favor the evolution of multiple herbicide-resistant biotypes through the accumulation of different resistant genes in an individual weed or weed population. From the Nebraska Crop Management Conference Proceedings.

Trial studying efficacy of products on Palmer amaranth

Palmer Amaranth Control in Dry Bean January 14, 2019

Residual herbicides applied at or before planting are critically important to controlling emerged Palmer amaranth in dry bean. Research at the Panhandle REC assessed the efficacy of PRE and pre-plant incorporated (PPI) residual herbicide programs.

Figure 1. Glyphosate-resistant Palmer amaranth infesting corn field in south central Nebraska. (Photo by Amit Jhala)

Glyphosate-Resistant Palmer Amaranth Field Day July 11 June 25, 2018

Is glyphosate-resistant Palmer amaranth a growing challenge? View field demonstrations and hear from experts at the Glyphosate-Resistant Palmer Amaranth Management Field Day Wednesday, July 11 at Carleton.

Photos of the Palmer amaranth and common waterhemp plants at cotyledon stage — (Left) Figure 1. Palmer amaranth cotyledons: long and narrow (Photos by Alfred Stark and Lowell Sandell) (Right) Figure 2. Common waterhemp cotyledons.

How to Differentiate Common Waterhemp and Palmer Amaranth Seedlings May 16, 2017

Growers should be on the lookout for common waterhemp and Palmer amaranth, which typically start emerging in the first or second week of May in Nebraska.

Watch for Palmer Amaranth in Conservation Reserve Program (CRP) Fields May 12, 2017

Palmer amaranth has not been confirmed in conservation plantings in Nebraska; however, the identification and occurrence of Palmer amaranth in CRP fields in Iowa has raised concerns among weed scientists and growers about its spread into conservation plantings in Nebraska and offer some suggestions for growers.

Glyphosate-Resistant Palmer Amaranth Confirmed in South-Central Nebraska March 15, 2017

Palmer amaranth (Amaranthus palmeri S. Wats.) is a C₄ dioecious species (separate male and female plants) native to the southwestern United States.

Photos of pigweed species — Figure 1. Common pigweed species found in the Nebraska Panhandle. Palmer amaranth and waterhemp are ALS-resistant. Images, from top to bottom in each column, are of seed, seedlings, and plants in the vegetative growth stage. (Source Nebraska Extension EC94-138)

Management of ALS-Resistant Palmer Amaranth and Waterhemp in the Panhandle January 6, 2017

Palmer amaranth and waterhemp in the Panhandle are resistant to ALS-inhibiting herbicides. While control of these weeds in dry bean can be challenging, corn, irrigated small grains, and sugarbeet make good rotation options for control. A combined pre/post treatment strategy controls weeds in the early part of the season when crop yield is most impacted and weed species are most susceptible to control inputs.

Depictions of Palmer amaranth in corn — Figure 1. (L) Palmer amaranth in corn and (R) a Palmer amaranth seedling. A member of the pigweed family, Palmer amaranth is a difficult to control broadleaf made even more difficult by its growing resistance to herbicides, including atrazine and HPPD inhibitors.

Managing Herbicide-Resistant Palmer Amaranth Field Day July 1, 2015

Learn how to get an edge on managing Palmer amaranth resistant to atrazine and HPPD-inhibitor herbicides Tuesday, Aug. 4 at a Nebraska Extension field day near Shickley.