The LL-GT27 soybean – what’s legal?

Source: Dr. Mark Loux, OSU Extension

We are starting to see the availability of soybean varieties with more than two herbicide resistance traits, which can expand the herbicide options, improve control, and allow multiple site of action tank mixes that reduce the rate of selection for resistance.  One of these is the Enlist soybean, with resistance to glyphosate, glufosinate, and 2,4-D.  As of this writing, full approval for the Enlist soybean is still being held up by the Philippines (because they can apparently).  The other is the LL-GT27 soybean, which has resistance to glyphosate, glufosinate, and isoxaflutole (Balance).  There is no label for use of isoxaflutole on this soybean yet, but it is legal to apply both glyphosate and glufosinate.  In Ohio, as long as neither label prohibits applying a mixture of two herbicides labeled for a specific use, it’s legal to apply the mixture.  So, it’s also legal to apply a mixture of glyphosate and glufosinate to the LL-GT27 soybean.  There is no label that actually mentions or provides guidance for this mixture, which does not affect legality, but could affect who assumes liability for the recommendation to apply a mixture if that matters to you.  Some seed companies are making the recommendation for POST application of the mix of glyphosate and glufosinate to the LL-GT27 soybean in printed materials.  Our interpretation after discussion with ODA, is that these materials are essentially supplements to labels, and so the seed company would assume some liability for the recommendation.

Continue reading

Achieving Full-season Waterhemp Control in Soybeans

Dr. Bob Hartzler and Meaghan Anderson, Integrated Crop Management News, and Iowa State University Extension and Outreach.

Although there are many ways weeds escape control in crop fields, one of the leading causes of waterhemp control failures is emergence of plants following postemergence herbicide (POST) treatments.

Waterhemp requires more than twice as many growing degree days to reach 50% emergence as giant foxtail or velvetleaf (Figure 1), resulting in much of the population emerging after mid-June.

The layered residual system is one of the best ways to reduce late-season waterhemp escapes in soybean. It involves a split application of herbicides with residual activity – the first application is made at or near planting, and then additional residual is included with the POST application (Figure 2). The additional residual herbicide extends activity later into the season than a single application, and is especially beneficial in years with heavy rains following planting.

Continue reading

Developing a long-term comprehensive weed management system – Part 2

Source: Iowa State University, (Edited)

Post 2 of a 4 post series.

As the end of the year approaches and we reflect on the 2018 growing season we need to look at what changes or improvements we need to make in our production plans for 2019.  Herbicide resistant weeds are continuing to create problems.  New, very invasive and harmful weed species (Palmer Amaranth and Waterhemp) are now prevalent in Knox County.  Therefore, a review of the effectiveness of your herbicides program is definitely in order.

To effectively battle these new weed problems, creating a comprehensive, all-encompassing weed control strategy is essential in today production agriculture.  Over the next 4 weeks I will share information developed by Meaghan Anderson and Dr. Bob Hartzler at Iowa State University on developing a long-term weed management system.

Last week’s post:   Herbicide program development: Using multiple sites of action

This week’s post: Herbicide program development: Using effective herbicide groups

After you’ve started working on a program that contains multiple herbicide groups (sites of action), you need to make sure you’re using multiple herbicide groups that will be effective against your target weeds. For most people, the target weed will be waterhemp. Others may have problems with giant ragweed, horseweed/marestail, or other weeds. Waterhemp is the target weed in my example, but consider what your most problematic weeds are to run through this exercise for yourself.

Things to consider when determining whether a herbicide is effective against your target weed include (1) whether the herbicide is labeled to control the weed and (2) whether your target weed is resistant to the herbicide group.

Let’s look at herbicides as if waterhemp is the weed that causes us the most issues. Here’s a table of herbicide groups used in Iowa crops.

Continue reading

Developing a long-term comprehensive weed management system.

Source: Iowa State University, (Edited)

As the end of the year approaches and we reflect on the 2018 growing season we need to look at what changes or improvements we need to make in our production plans for 2019.  Herbicide resistant weeds are continuing to create problems.  New, very invasive and harmful weed species (Palmer Amaranth and Waterhemp) are now prevalent in Knox County.  Therefore, a review of the effectiveness of your herbicides program is definitely in order.

To effectively battle these new weed problems, creating a comprehensive, all-encompassing weed control strategy is essential in today production agriculture.  Over the next 4 weeks I will share information developed by Meaghan Anderson and Dr. Bob Hartzler at Iowa State University on developing a long-term weed management system.

This week’s post:   Herbicide program development: Using multiple sites of action

With the stagnant development of new herbicides and weeds seemingly evolving herbicide resistance faster than ever before, it’s important to maximize the usefulness of every herbicide application. A new herbicide site of action (or herbicide group number) for use in corn and soybean production has not been discovered since the early 1980s. According to Dr. Ian Heap with www.weedscience.org, since the 1980s, the confirmed number of unique cases of herbicide resistance globally is increasing at a rate of about 12 discoveries per year.

Continue reading

Inversion and Drift Mitigation – Workshop on December 14

Inversion and Drift Mitigation Workshop
Dec. 14, 2018 • 10 a.m. – noon

10 – 11 a.m. Weather Conditions and Potential Inversions
Speaker: Aaron Wilson, Weather Specialist & Atmospheric Scientist, OSU Extension, Byrd Polar & Climate Research Center

11 – noon Using FieldWatch to Communicate
Speaker: Jared Shaffer, Plant Health Inspector, Ohio Department of Agriculture

Two choices for attending the workshop:

Attend in person (pre-registration required, limited to the first 75 people registered)
Ohio Dept. of Agriculture • Bromfield Administration Building
8995 E. Main St., Reynoldsburg, OH 43068
Click here to register

Attend virtually:
Link coming soon – no pre-registration required

No cost to attend. Core commercial and private pesticide recertification credits available only athe Reynoldsburg in-person location. Limited to the first 75 registered. No recertification credits given for virtual/internet attendees.

For more information about the workshop, contact:
Cindy Folck, folck.2@osu.edu
614-247-7898

Event sponsored by OSU Extension IPM program and the USDA NIFA Crop Protection and Pest Management Competitive Grants Program (Grant number 2017-70006-27174).

 

Precautions for Dicamba use in Xtend Soybean

Ohio, Indiana, and Illinois are heavily infested with weeds resistant to glyphosate (group 9), PPO inhibitors (group 14), and ALS inhibitors (group 2). This has greatly reduced the number of effective postemergence herbicides for controlling these weeds in Roundup Ready 2 (RR2) soybeans. Adoption of Roundup Ready 2 Xtend (glyphosate and dicamba resistant – RR2 Xtend) soybeans and use of dicamba-based herbicides is one option for managing resistant weed populations. Keep in mind that selection for dicamba resistance occurs each time dicamba is applied, and over reliance on this technology will lead to the development of dicamba-resistant weed populations.

The extension weed science programs at The Ohio State University, Purdue University, and the University of Illinois recently collaborated to revise suggestions and precautions for use of dicamba in dicamba-resistant soybean.  The United States Environmental Protection Agency renewed labels of Xtendimax, Engenia, and FeXapan last October, and this updated extension weed science publication offers additional suggestions to help further reduce off-target dicamba movement.

Click here to view the publication

Registration of Dicamba for Use on Dicamba-Tolerant Crops

The EPA extended the registration for two years for over-the-top use of dicamba to control weeds in fields for cotton and soybean plants genetically engineered to resist dicamba. This decision was informed by extensive collaboration between EPA, the pesticide manufacturers, farmers, state regulators, and other stakeholders. The registration includes label updates that add protective measures to further minimize the potential for off-site damage.  The registration will automatically expire on December 20, 2020, unless EPA further extends the registration.

The following label changes willbecome effective this year.

  • Only certified applicators may apply dicamba over the top (those working under the supervision of a certified applicator may no longer make applications)
  • Prohibit over-the-top application of dicamba on soybeans 45 days after planting and cotton 60 days after planting
  • For cotton, limit the number of over-the-top applications from 4 to 2 (soybeans remain at 2 OTT applications)
  • Applications will be allowed only from 1 hour after sunrise to 2 hours before sunset
  • In counties where endangered species may exist, the downwind buffer will remain at 110 feet and there will be a new 57-foot buffer around the other sides of the field (the 110-foot downwind buffer applies to all applications, not just in counties where endangered species may exist)
  • Clarify training period for 2019 and beyond, ensuring consistency across all three products
  • Enhanced tank clean-out instructions for the entire system
  • Enhanced label to improve applicator awareness on the impact of low pH’s on the potential volatility of dicamba
  • Label clean up and consistency to improve compliance and enforceability

Click Here To Read The Entire Article

 

 

Changes Made to Ohio’s Prohibited Noxious Weeds List

Source: Peggy Kirk Hall, Associate Professor, Agricultural & Resource Law (edited)

Palmer Amaranth

New changes to Ohio’s prohibited noxious weeds list took effect Friday, September 14th.  The Ohio Department of Agriculture (ODA) added 13 new species to the list, and removed 3 species.

On this blog, throughout the spring and summer I posted information and identification tips on each of the 21 Ohio noxious weeds.  This information can be easily found by typing “noxious weeds” in the Search this blog… box found on any page within our blog.  In the upcoming weeks, I will add similar posts for each of the new weeds added to this list.

Added to the list of prohibited noxious weeds are:

  • Yellow Groove Bamboo (Phyllostachys aureasculata), when the plant has spread from its original premise of planting and is not being maintained.
  • Field bindweed (Convolvulus arvensis).
  • Heart-podded hoary cress (Lepidium draba sub. draba).
  • Hairy whitetop or ballcress (Lepidium appelianum).
  • Perennial sowthistle (Sonchus arvensis).
  • Russian knapweed (Acroptilon repens).
  • Leafy spurge (Euphorbia esula).
  • Hedge bindweed (Calystegia sepium).
  • Serrated tussock (Nassella trichotoma).
  • Columbus grass (Sorghum x almum).
  • Musk thistle (Carduus nutans).
  • Forage Kochia (Bassia prostrata).
  • Water Hemp (Amaranthus tuberculatus).

Removed from the list are:

  • Wild carrot (Queen Anne’s lace) (Daucus carota L.).
  • Oxeye daisy (Chrysanthermum leucanthemum var. pinnatifidum).
  • Wild mustard (Brassica kaber var. pinnatifida).

Continue reading

Harvest Considerations to Reduce Weed Seed Movement

Source: Iowa State University Extension

Weed seed spread by a combine

Harvest is just around the corner for many Iowa farmers and now is a good time to consider options to reduce movement of weed seed between fields with harvest equipment. While we may not think of it during harvest time, combines are extremely effective at transporting seed from field to field. A few precautions leading up to harvest and during harvest can help manage any escaped problem weeds.

Prior to harvest, scout fields for escaped weeds since weeds are easier to see after crops have matured. This is important to identify problem fields or areas for next year. Your notes about weed problems are critical to choosing effective management tactics for next year, so make this a priority prior to harvest. In some situations scattered weeds could be removed from the fields prior to harvest. It is much easier to manage weed issues before they drop mature seed or before that mature seed goes through a combine.

… Click here to see full article