It’s no secret that the 2022 crop year will be about input cost control and management. Almost everything, from fertilizer to farm machinery has risen in price, and herbicides are no exception.
Production disruptions and material shortages have resulted in limited supplies of glyphosate (Roundup) and glufosinate (Liberty), and prices have increased substantially. As you prepare for spring herbicide applications, here are some things to consider:
Managing limited supplies should start with an analysis of your herbicide program. Opportunities to omit or reduce the rate of glyphosate or glufosinate include fields treated the previous fall or having low weed pressure, where the POST program is comprehensive enough to control weeds that escape the burndown, such as the Enlist E3, XtendFlex and LL GT27 soybean programs.
In these cases, glyphosate may be limited to the POST program. Additionally, there are generally more options for burndown and POST applications in corn, so it may be best to save limited stocks for soybeans.
Because it’s difficult to exclude glyphosate from spring burndowns, it may be the best place to use limited supplies. Lowering rates to 0.38 lb ae/A will control most annual grasses, and adding Sharpen will enhance control of rye, ryegrass and marestail. Additionally, Glufosinate, Enlist Duo or XtendiMax/Engenia can be used for many broadleaf weeds.
However, where residual herbicides are omitted or do not provide adequate control, POST treatments will likely struggle without glyphosate, so the use of residuals will be necessary.
Common burndown programs typically contain glyphosate and one or two other products, such as 2,4-D or dicamba, to increase the weed control spectrum. If omitting glyphosate, follow the same strategy and use at least two herbicides with substantial activity. Increasing the rate of those components, when done in accordance with label guidelines, should also help. If you’re omitting glyphosate grass control is key, and products such as gramoxone, rimsulfuron in corn, and quizalifop and clethodim in soybeans can work. For burndown of legume covers prior to corn, clopyralid and dicamba are effective herbicides, and gramoxone plus atrazine or metribuzin can terminate cereal rye. In soybeans, chlorimuron products will have burndown activity as well. However, glyphosate will be necessary to control annual ryegrass or little barley.
Finally, good product management will help to stretch thin supplies. First, take steps to maximize herbicide activity including using the correct adjuvants and following label recommendations for nozzles, carrier volume, pressure and speed. Also, do not mix group 1 herbicides with dicamba or 2,4-D, as herbicide antagonism can reduce grass control. Finally, check on the availability of premix herbicides that may contain glyphosate or other herbicides unavailable as single ingredients, such as Sequence, Halex GT, Mes-O-Sate, Acuron GT, Extreme, and Flexstar GT. Unfortunately, some challenges may lie ahead for 2022, so please take the time to review you options and develop a contingency plan to deal with any disruptions that may come down the line.
Zach Larson is the Penn State Extension agronomy educator for Blair County. He can be reached at 814-414-0582.
