With Australian no-tillers dealing with some of the worst weed resistance issues in the world, the country’s growers are adopting a “zero tolerance policy” or a “take no prisoners” approach to weed control. 

It’s an idea that may spread to North America as herbicide resistance continues to be a serious concern for many U.S. no-tillers. In fact, results from last winter’s annual No-Till Farmer Benchmark Study indicates 70% of no-tillers suspected or confirmed herbicide resistant marestail (horseweed) in their fields during 2018. 

Avoid Weed Seed Buildup

Drew Lyon recently summarized the latest developments and trends in herbicide resistance management from scientists at the Australian Herbicide Resistance Initiative located at the University of Western Australia. The Washington State University weed scientist says the most significant Australian ideas for managing herbicide resistance focus on reducing and maintaining seed bank levels:

1. Renewed efforts needed in herbicide discovery. Herbicide resistance, particularly with glyphosate, has encouraged several ag chemical companies to recently invest more heavily in product discovery than they have over the past several decades. 

2. Trait stacking in herbicide-resistant crops. This would include releasing varieties with resistance to two or three different herbicide modes of action. Even though the idea has potential, few weed scientists believe it’s a long-term solution since it could eventually lead to weeds that are resistant to multiple modes of action.

3. Increased use of pre-emergence herbicides. Pre-emergence herbicides can provide more effective early season weed control. By reducing early-season weeds, these herbicides lessen the potential for…