Weeds

Dicamba battles continue: court allows dicamba use

There was a great deal of action last Friday in the case that vacated the registrations of XtendiMax, Engenia, and FeXapan dicamba-based products.  Despite a barrage of court filings on Friday, however, nothing has changed the current legal status of the dicamba products in Ohio, and Ohio growers may use existing stocks of the products now. Still, they must end-use by June 30th, 2020.

Here’s a rundown of the orders that the Ninth Circuit Court of Appeals issued in the case last Friday:

The court denied the emergency motion that the petitioners (National Family Farm Coalition, Center for Food Safety, Center for Biological Diversity, and Pesticide Action Network North America) filed on June 13th.  That motion asked the court to enforce its previous mandate to vacate the registrations, to prevent any further use of the products, and to hold the EPA in contempt for issuing the Cancellation Order the agency had made that allowed continued use of existing stocks of the products.  The court did not provide its reasoning for denying the motion. Continue reading →

Distribution of Waterhemp and Palmer Amaranth in Ohio

By: Mark Loux and Bruce Ackley, OSU Extension

The maps that accompany this article show our current knowledge of waterhemp and Palmer amaranth distribution in Ohio.  These are based on information from a survey of OSU Extension County Educators, along with information we had from samples submitted, direct contacts, etc. We still consider any new introductions of Palmer amaranth to be from an external source (brought in from outside Ohio) – hay or feed, infested equipment, CRP/cover/wildlife seedings.  Palmer is not really spreading around the state, and as the map shows, we have had a number of introductions that were immediately remediated.  The number of counties where an infestation(s) is being managed is still low, and within those counties, the outbreak occurs in only a few fields still.  Waterhemp is much more widespread in Ohio and is spreading rapidly within the state from existing infestations to new areas via equipment, water, animals, etc.  We do not have Ag Educators in all counties, and even where we do, infestations can occur without us knowing about them.  Feel free to contact us with new information to update the maps. Continue reading →

Cover Crop Termination

Cereal RyeBy: Alyssa Essman and Mark Loux, Ohio State University Extension, Weed Science Specialist

The 2019 growing season came and went and left many fields in a state of disarray heading into 2020. Many growers that were unable to plant decided to use cover crops, to reduce soil erosion and provide some weed suppression during the extended fallow period. Terminating these cover crops using the right methods at the right time will be critical to ensure timely planting and prevent the cover crops from competing with cash crops. The three main methods of cover crop termination are natural (species that winter kill), chemical, and mechanical. Cover crops may also be bailed, grazed, or harvested as silage. Most species require some sort of management decision for termination. Cover crop species, growth stage, weather, and cover cropping goals should all be considered when planning termination method and timing. These decisions require a balance between growing the cover long enough to maximize benefits and terminating in time to prevent potential penalties to the following cash crop. Continue reading →

Weed Management in Ohio, Update 2019

By: Harold Watters, OSU Extension Ag Crops Field Specialist

Our OSU Extension AgNR educators observed soybean fields across the state again this fall to see what was out there for our annual fall soybean weed survey. I was supposed to share this early enough so you could at least get a fall application on to get a head start on controlling marestail, but it seems we have more problems than that to deal with.

Statewide our most frequently observed weed problem was again marestail. It was present in 36% of the fields. The second most likely observation was weed-free — at 29% of the fields. That’s a big jump over several years ago, and likely due to LibertyLink, Enlist, and Extend soybeans. Third, fourth and fifth places in a three-way tie were giant ragweed, volunteer corn and then giant foxtail (or just generic grass) — all in about 19% of the fields. Next, and getting ever more widespread, is waterhemp at 15% of the fields across the state. Continue reading →