Two recent articles that appear on farmprogress.com deserve the attention of Midsouth soybean producers as they plan for the 2021 crop.
The first is an article written by Forrest Laws titled “Eight tips for controlling problem weeds in cotton and soybeans”. In this article, advice for handling weed management issues is provided by Drs. Larry Steckel (UT Extension Weed Specialist), Tom Barber (UA Extension Weed Scientist), Jason Bond (MSU Weed Scientist), and Eric Prostko (UGA Extension Weed Scientist). Major points proffered by these distinguished Weed Scientists/Specialists follow.
• At the very least, apply residual preemergence (PRE) herbicides at planting. Apply herbicides with at least two modes of action that will control targeted weeds.
• Consider an overlay of residual herbicides, with one application preplant (can be applied with burndown), a second at planting, and possibly a third applied postemergence (POST). Again, apply herbicides with at least two different modes of action that will control the targeted weed(s).
• Do not tank-mix glyphosate with a dicamba herbicide if grasses are part of the targeted weed complex.
• Use POST-directed applications of herbicides where possible. This will likely provide more flexibility on the herbicides that can be used in POST applications.
• Use a hooded sprayer if needed to minimize drift.
• Keep an eye on fields after harvest to ensure that surviving weeds do not produce seed, and control surviving weeds to minimize the amount of weed seed that are returned to the soil weed seedbank.
• Consider fall planting of a cereal (e.g. cereal rye or wheat) cover crop to reduce the amount of Palmer pigweed that has to be controlled later.
• Consider tillage as a last resort if large Palmer pigweed plants are present. Remember that weeds of this species that are larger than 6 in. tall will not be easily controlled with a herbicide, if at all.
The second article is titled “Get most bang for your buck with soybean seed treatments”. In this article, reminders of which seed treatment products to use and when to use them depending on planting environment are provided. These tips are summarized below.
• Seed treatment products may contain fungicides, insecticides, and nematicides that target pathogens/pests of planted soybean seed.
• Using past experience with individual fields to be planted to soybeans, apply those seed treatment products that contain only the pesticide component that will target the pathogen/pest that is known to be present.
• At the very least, always apply a broad-spectrum fungicide seed treatment regardless of planting date. Click here and view the available choices in Table 1.
• Consider a seed treatment that contains an insecticide for seed that will be planted early or for plantings made into cover crop residue. Click here and view the available choices in Table 2.
• Consider applying an inoculant in certain situations. Click here to access a discussion about when this should be done.
• There are nematicide seed treatment products that can be considered for fields with a history of problems from these pests. Nematode-protectant seed treatments are intended to supplement current nematode management strategies, and therefore should be used in coordination with growing varieties with SCN resistance genes and rotation to nonhost crops. Click here to access a discussion about using nematicide seed treatments.
An updated White Paper on this website thoroughly covers the use of soybean seed treatments.
Composed by Larry G. Heatherly, Nov. 2020, email@example.com