By Darren Hefty
Pre-emerge herbicide use in wheat is on the rise because these products are increasing yields thanks to improved weed control. Here is our quick evaluation of the top 3 wheat products available:
Sharpen is a PPO (Group 14) with a fast burndown and good residual. Sharpen must be sprayed prior to wheat emergence. Sharpen controls only broadleaves, and it makes a great tankmix partner for Roundup, especially when you go to the 2 or 3 oz. per acre rate.
Pre-Pare is an ALS (Group 2) with burndown and residual activity on foxtails, wild oats and even cheat. It also has some activity on mustards, shepherdspurse, canola and other broadleaves. The normal labeled rate is 0.3 ounces, which works well in lower soil pHs. In high pH areas, many growers are cutting back the rate to 0.2 ounces to minimize the chance of any crop response. Pre-Pare is more active in high pH soils and often still does a very good job with weed control even at a reduced rate.
Zidua is a Group 15 residual-only product (won’t kill emerged weeds) similar to Harness or Outlook in corn. We are excited about Zidua because it has a different site of action than ALS or ACCase products; it can be used pre or post; and it has activity on Italian ryegrass, foxtails, wild oats, downy and Japanese brome, cheat and a number of broadleaf weeds.
If you’ve never used a pre-emerge herbicide and are planting spring wheat this year, split a few fields and see the difference in yield and weed control you can achieve by using a pre. I’m confident you will find, as many other growers have, that it’s well worth the time and investment.