By Darren Hefty
Looking for a way to get higher yields, better drought tolerance, reduce your chances of having a problem with resistant weeds, and get a little more flexibility for spraying your post-emerge herbicides? You’re in luck. There are a number of herbicides now available for pre-emerge use in wheat that can help you do just that. In fact, there are even more herbicides that should be labeled for pre-emerge use in wheat in the next few years.
Here’s a rundown of the products available now and one that should be coming soon:
- SHARPEN is an excellent burndown partner for Roundup and provides some residual control for at least a couple weeks in most cases. Sharpen is in the PPO family of herbicides and adds another site of action to your wheat herbicide program. Sharpen burns broadleaf weeds down quickly but has limited to no activity on grass weeds. All applications of Sharpen must be made before the crop is up to avoid potential injury. The standard recommendation is to use 2 oz. per acre of Sharpen with 1 gallon of methylated seed oil (MSO) and 17 pounds of ammonium sulfate (AMS) per 100 gallons. If broadleaf weeds like resistant kochia are your main problem, Sharpen would be the lead recommendation pre-emerge.
- PRE-PARE is the leading recommendation for controlling emerged grasses and providing residual control for grasses that may come up later. Pre-Pare has the same active ingredient as Everest 2.0 and does a very good job on foxtails and wild oats while also providing suppression on cheatgrass. The full labeled rate of Pre-Pare is 0.3 ounces per acre; but since it can be a very active compound in high pH soils (above 7.4 pH), we normally take the cautious approach and recommend using 0.2 ounces per acre. In low pH soils, Pre-Pare is less active; and many farmers will choose to run with the full rate of 0.3 ounces. I look at it this way, though. No pre-emerge herbicide should be expected to control all your weeds all season. You’re going to have to come back with a post-emerge spray to clean up any escapes. So why take a chance on having injury even in just a few areas of your field? Of course, the choice of which rate to run is up to you.
- VALOR is another PPO herbicide, but it is not commonly used in front of wheat. You need to apply it at least 30 days in advance, and crop injury is possible if you don’t have sufficient rainfall soon after application to distribute it in the soil.
- ZIDUA is currently not labeled for use in wheat or other cereals, but we anticipate it being labeled in the next few years. It controls both grasses and broadleaves with residual activity. Keep an eye out for it in university and private trials around your area this year. We believe Zidua will be a good option. It’s a Group 15 herbicide like Harness, Surpass, Dual, and Outlook in corn.