Episode 5

Published on:

9th Apr 2024

The Fight Against Resistant Weeds With Dr. Brian Jenks

Dr. Brian Jenks is a weed scientist at North Dakota State University based in Minot. He has been in this role since 1997 and over that time he has seen an alarming rise in resistance to many of our herbicides from certain weeds, especially in kochia. In this episode Jenks discusses the resistance problem and some of the work underway to help farmers manage these weeds that are getting tougher every year to control. He also shares an exciting new offering from the Ag Genotyping Center to identify resistance.

“I've been polling farmers this winter and the most common answer I get is about 80%. Farmers think about 80% of their kochia is roundup resistant. So it's a majority of the kochia and we know that there's group 14 resistance out there to Aim and Sharpen. So if we want to control kochia in a burn down, we need to know  if Aim and Sharpen are going to work for us.” - Dr. Brian Jenks

Spray droplet size, travel speed when spraying and the height of the kochia when treated are all factors that greatly affect the success of herbicide use. True resistance however will be able to survive each of these adjustments. Developing new mechanisms of action and products to circumvent the resistance is a lengthy difficult process with no clear immediate solution in site. With resistance observed in many commonly used herbicides, gramoxone seems to be the only one that remains consistently effective. Unfortunately resistance is likely to emerge here too without other measures being taken.

“The worst thing we can do is probably a two year rotation where we're using the same herbicides and the same crops over and over.  I'm optimistic if we can diversify our crops to get a minimum of 3, 4, 5 crops in the rotation,  and then use 5, 6, 7 different modes of action with our herbicides.” - Dr. Brian Jenks

This Week on Growing Pulse Crops:

  • Meet Dr. Brian Jenks, a weed scientist at North Dakota State University
  • Explore the growing problem of herbicide resistant kochia and the impact this problem will have on pulse crop production
  • Understand the significance of different spray techniques and following up on spray treatments with early season monitoring

Growing Pulse Crops is produced by Dr. Audrey Kalil and hosted by Tim Hammerich of the Future of Agriculture Podcast

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About the Podcast

Growing Pulse Crops
The science and business of farming field peas, chickpeas, and lentils
This show features the latest in research, agronomy, and economics of pulse crops (peas, chickpeas, lentils, etc.).

Demand for these nutrient-dense, high-protein foods continues to grow. There is also interest from farmers to include more pulses into diverse rotations for benefits like nitrogen fixation and soil health.

But the industry continues to face challenges, and we are eager to address these head on. So if you’re a pulse grower or in any way interested in these important crops, hit subscribe and stay tuned for future episodes. We’ll be back with plenty of information about challenges pulse farmers are facing throughout the U.S. and what solutions are working.

Brought to you by the Pulse Crops Working Group with support from the North Central IPM Center and USDA NIFA.

About your host

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Tim Hammerich

I share stories about agriculture, agtech, and agribusiness on podcasts and radio.