Published on Tuesday, April 30, 2019
Across the Midwest, finding a window to do field activity has been very challenging this spring. Many farmers find themselves wondering if they should change any of their management strategies as planting continues to be delayed. But, before you make any changes to your 2019 plans, let’s discuss some factors that could influence your growing season.
Managing a Carpet of Weeds: How to Start Clean
No matter what crop you are planting, we always recommended starting clean. However, with the minimum amount of fall burndown applied last fall and delayed field activity this spring, farmers may be facing a carpet of weeds. As the weeds continue to grow and become larger in size, control can become more difficult, especially for contact products. In these instances, carrier volume is key to achieving excellent control, especially for contact products. As weeds grow larger, the rate of herbicides required will change so it’s critical to re-read the label to ensure the proper rate of herbicide is applied and the size of weed is still on label.
Burndown Products: With or Without Residual Activity?
Products such as Sharpen® and metribuzin can have residual activity depending on the rate applied when compared to products such as Gramoxone® that have no residual activity. If there is a break in the weather and the sprayer can carry but planting is delayed, using a product with residual activity can reduce the number of new flushes of weeds until you are able to plant. However, depending on the rate applied and crop planted, products that have residual activity may have a plant back restriction. If planting can occur right away, using a product such as Gramoxone could be a good fit since it would not have a plant back restriction.
SIL 2018 fall vs. spring burndown study in soybeans
What if a burndown was applied but planting was delayed and new flushes of weeds have emerged? If there is weed pressure present at the time of the pre-emerge application, a product with post-application activity will be necessary to control the escapes. For a residual or pre-emerge herbicide to work, it must reach the soil surface. Therefore, if large amounts of weeds are present, a second burndown application may be necessary.
The longer that burndown is delayed, the more likely the weed spectrum you face might change. In early spring, we are primarily worried about winter annuals such as marestail. However, as temperatures begin to rise, you may see new flushes of marestail. Summer annuals such as giant ragweed and waterhemp will follow, so if these are some of the weeds you face, be sure to select burndown products that are effective on glyphosate and ALS resistant populations.
No Nitrogen – No Problem
Just like your fall or spring burndown applications, finding prime opportunities to apply anhydrous has been limited this year. If you have yet to apply any nitrogen, you may be wondering what you should do. For starters, your priority should be on planting and making sure the planter is running when conditions are prime. Click here to learn more about what to do if you have yet to apply nitrogen to your fields.
To Plant or Not to Plant
Now that you have a strong plan in place for weed control, the question remains… when should you plant? Beck’s PFR data has shown that earlier planting provides the maximum yield potential. However, pushing the envelope and planting into marginal conditions can negatively impact yields.
SIL Corn Planting Date Data
SIL Soybean Planting Date Data
In 2017, our Ohio PFR site set up a study to measure how delayed emergence can affect yield. When planting into cool, wet conditions, it took six days for all the plants to emerge. However, in prime conditions, all the plants emerged within three days. Fields in which all plants emerge after 24 hours of the first emerged plant had less yield potential compared to plants that have emerged within 24 hours from the first emergence. Though it’s tempting to push the envelope and plant as early as you can, planting into prime conditions can result in more even emergence and increased yields.
If you have any questions about your planting plan, please contact your local Beck's representative.
Author: Joe Bolte
Categories: PFR, PFR Reports
Tags: Nitrogen, Farmserver, Delayed planting, Planting Date, Spring Burndown, Fall Burndown, Precision Farming, pre-emerge herbicide applications, residuals