5 Tips for Successful Weed Control
1. Look at last year.
Evaluate the performance of last year’s weed-control strategy to see what worked well and what you would like to switch up. Note the most prevalent weeds and devise your plan for controlling them first.
2. Start with a clean field at planting.
Use tillage or an effective burndown application to get your crop off to a weed-free start. An effective herbicide strategy consists of using multiple, effective modes of action, correct herbicide rates, and timely postemergence applications. In no-till cropping systems, we like to recommend doing a fall burndown. Fall-emerging marestail is very difficult to control with herbicides in the spring. If you did not do a fall burndown, your spring burndown will need to use effective modes of action to control any winter annuals and/or marestail in your fields.
Farmers Pride recommends using three effective modes of action for any weed-management program. This strategy consists of residuals and post-emergent herbicides. The post-emergent herbicides should be applied in a timely manner and offer another residual to protect against later-emerging weeds such as waterhemp and Palmer amaranth. This can be an effective strategy for both traditional tillage and no-till systems. Be sure to check herbicide labels for plant growth restrictions on post-emergent herbicides.
3. Choose the right adjuvant.
Imagine you’ve invested in a new state-of-the-art planter. You’ve done all the planter maintenance and calibration to set up for a successful spring, but in the midst of all that prep, you forgot to fuel up your tractor. Without the tractor, that expensive planter can’t do its job. You can use the same analogy for adjuvants and crop protection products. You might choose to invest in the most expensive herbicide, fungicide and insecticide, but they won’t perform as well as they should without the right adjuvant.
“Adjuvant” is a broad term used for any substance that can improve the performance of a crop protection product. There are different classes of adjuvants, including:
Water conditioners — Help ensure herbicides get into plants and don’t get tied up by cations in hard water.
Nonionic surfactants — Help spread pesticides on the leaf’s surface to improve plant coverage.
Crop-oil concentrates — Help slow the drying of a herbicide droplet on the leaf and improve penetration into the leaf.
Methylated seed oils — Help improve penetration through waxy plant cuticles and are usually used in more extreme environments.
Drift and deposition aids — Help minimize particle drift by reducing driftable fine particles in a solution and improve product coverage deeper into a crop’s canopy.
Many of the new herbicides recommend or require certain types of adjuvants for safety and efficacy reasons. Talk with your Farmers Pride Agronomist about what adjuvant would work best for your weeds and herbicide programs.
4. Know your weed emergence schedule.
As mentioned earlier, marestail can emerge in the fall, but it is one of the earlier weeds that also emerges in the spring. Another early emerger is giant ragweed. With these weeds, an early burndown application is crucial to achieve adequate control. Waterhemp and Palmer amaranth have a much longer period of emergence — from early spring to peak emergence in June and early July, so make sure you use an effective preemergence herbicide, layered with residual post emergent herbicides for late-emerging Palmer amaranth and waterhemp.
5. Making the most of spray applications.
If spray applications are done right the first time, they can save dollars and headaches in the long run. Adding the right adjuvant is just one step you can take to make sure you are optimizing the performance of your crop protection products. In addition to adjuvants, ensure that your sprayer is calibrated correctly, you have the right nozzles and an adequate spray volume for appropriate plant coverage, and that you have read the product label.