A New Material for Walnut Blight

Walnut blight is serious for Northern California growers and protecting trees from blight is more difficult these days due to the increased resistance to copper materials. Luke Milliron is a UCANR orchard crops farm advisor for Butte, Tehama and Glenn Counties in Northern California.

It's really exciting that in the last couple of years we've been able to use this new material Kasumin product and it's not that is any more effective when paired with copper or with Mancozeb, but it's equally effective to our gold standard of copper and Mancozeb,” noted Milliron. “Therefore we now have three materials that have a different mode of action—copper, Mancozeb and Kasumin, and when you rotate those in two part rotations together, you are finally doing some practicing of resistance management which this industry desperately needs

And the EPA certainly wants to reduce the amount of copper being sprayed on crops.

“EPA has been reducing that total pounds of allowed copper per year. That's been coming down over the years,” noted Milliron. “If that continues to come down, that is another place where having a material like Kasumin could really help because then your rotating with copper in one instance, and then you could have a Kasumin/Mancozeb rotation where you're not really needing to use copper, so you're saving on copper.”