- DTN Headline News
Weed Fight
Wednesday, December 7, 2016 7:38AM CST


By Pam Smith
DTN Progressive Farmer Crops Technology Editor

STARKVILLE, Miss. (DTN) -- The South is at war with weeds. Some 280 participants packed into a town meeting here on Monday to talk about how to regain the upper hand against a growing list of resistant adversaries such as Palmer pigweed, Italian ryegrass and marestail.

The meeting was the first of a series of half-day regional workshops being sponsored by the Weed Science Society of America (WSSA). It's part of a national effort to develop research and regulatory priorities directly from those attempting to cope with the problem -- farmers, land managers, crop consultants and industry representatives.

The room resembled a spot in the field where the sprayer missed, as people packed in to share thoughts and brainstorm. Larry Steckel, University of Tennessee weed scientist, and other organizers of the event, expected a good turn out, but were slightly stunned by the response.

The drama over dicamba this past season spiked interest, Steckel said. Crop injury caused by dicamba in some parts of the South this year and concerns about how to safely use that herbicide and 2,4-D in new cropping systems, drifted in and out of the conversations. However, participants mostly focused on what keeps grower decision-making considerations and the impediments to implementing herbicide resistance management strategies. The thoughts will be compiled with other regions and forwarded to USDA and other decision makers.

Some of the messages identified during the Mississippi meeting included:

-- The increasing cost of weed control goes beyond mere cost of the product. Proper management of herbicide-resistant weeds is a year-long process that requires time management and additional labor that consumes resources beyond ratcheting herbicide costs.

-- There's a tremendous need for new herbicide chemistries and to speed up the regulatory approval process.

-- Answers can no longer come exclusively from the jug. Cover crops, mechanical seed destruction, crop rotation, tillage and a systems approach to managing weeds is now a reality.

-- Using multiple sites of action and overlapping residual herbicides all season long are now part of herbicide resistance management practices, but many Southern growers are still finding the need to use manual removal of herbicide-resistant weeds.

-- Getting across acres while weeds are at a susceptible size gets more and more difficult as water volumes increase and weather intervenes to reduce the number of viable spray days.

-- Stacking technologies together rather than being forced to choose one platform over another would help with resistance management.

-- The entire agriculture community has a vested interest in weed resistance. Increasing dollars to control the issue depletes what growers have to spend in other areas. The desire for more intelligent sprayers and integrated weed-seed destruction, for example, will require machinery manufacturer involvement.

-- There were requests for EPA and other regulatory decisions to be more science-based decisions rather than political.

-- Profitability will challenge herbicide resistance management plans, particularly in high cash rent areas where land has a high turnover rate among operators.

-- The need for continuing education is critical. Weed control has become increasingly complex, and even if everything is done right, nature finds a way to overcome. The desire to have an easy system, like the Roundup Ready system of the past, is still a mental hurdle to successful herbicide resistance management.

According to the International Survey of Herbicide Resistant Weeds (weedscience.org), there are currently 477 unique cases (species "x" site of action) of herbicide-resistant weeds globally, with 251 weed species involved (146 dicots and 105 monocots). Weeds have evolved resistance to 23 of the 26 known herbicide sites of action and to 161 different herbicides. Herbicide-resistant weeds have been reported in 90 crops in 66 countries.

Glyphosate resistance in the U.S. has brought national attention on resistance. There are now 36 weed species resistant to glyphosate globally. Growers have reached for other chemistries, and that is putting pressure on those chemistries. Steckel noted that the South is now experiencing increasing problems with resistance to PPO-inhibitors. Although there is no known resistance to glufosinate, the herbicide used with LibertyLink technology, weed scientists want growers to take the proper steps to retain the life of that system. Steckel noted that approximately 50% of the cotton in his state is now hand weeded. Palmer amaranth is the driver weed, but growers said Italian ryegrass is also problematic.

Those interested in attending one of the upcoming regional meetings should check with WSSA for more details: http://wssa.net/…. Reservations are necessary to attend as the number of people attending could be limited. The WSSA site also has more herbicide resistance information.

The Mississippi meeting was held in conjunction with the Mississippi State University 2016 Row Crop Short Course, which continues through Dec. 7. On Tuesday, Mississippi growers drilled down on what they will have to do to manage new herbicide technologies.

Mississippi has additional regulations pending that would tighten the upper-end wind-speed allowance when spraying approved dicamba formulations in tolerant crops. Mississippi growers will likely see wind speeds held to 3 to 10 mph, compared to the XtendiMax label, which allows 3 to 15 mph. Growers will also be required to take a synthetic auxin herbicide learning module, but when they would need to take that course is still under discussion.

Pamela Smith can be reached at pamela.smith@dtn.com

Follow on Twitter @PamSmithDTN

(BAS\AG\SK)


blog iconDTN Blogs & Forums
DTN Market Matters Blog
Editorial Staff
Monday, December 5, 2016 11:28AM CST
Monday, November 28, 2016 11:01AM CST
Wednesday, November 23, 2016 11:18AM CST
Technically Speaking
Darin Newsom
DTN Senior Analyst
Saturday, December 3, 2016 9:24AM CST
Thursday, December 1, 2016 5:08AM CST
Thursday, December 1, 2016 5:06AM CST
Fundamentally Speaking
Joel Karlin
DTN Contributing Analyst
Wednesday, December 7, 2016 10:45AM CST
Thursday, December 1, 2016 10:13AM CST
Wednesday, November 30, 2016 11:08AM CST
DTN Ag Policy Blog
Chris Clayton
DTN Ag Policy Editor
Friday, December 9, 2016 9:30AM CST
Wednesday, December 7, 2016 12:59PM CST
Tuesday, December 6, 2016 1:55PM CST
Minding Ag's Business
Marcia Taylor
DTN Executive Editor
Friday, December 9, 2016 1:30PM CST
Friday, December 2, 2016 3:36PM CST
Tuesday, November 8, 2016 9:38AM CST
DTN Ag Weather Forum
Bryce Anderson
DTN Ag Meteorologist and DTN Analyst
Wednesday, December 7, 2016 11:20AM CST
Thursday, December 1, 2016 2:10PM CST
Wednesday, November 30, 2016 2:11PM CST
Friday, December 9, 2016 3:05PM CST
Tuesday, December 6, 2016 1:33PM CST
Thursday, December 1, 2016 3:56PM CST
DTN Production Blog
Pam Smith
Crops Technology Editor
Tuesday, December 6, 2016 5:19PM CST
Friday, November 4, 2016 10:59AM CST
Friday, October 14, 2016 3:27PM CST
Harrington's Sort & Cull
John Harrington
DTN Livestock Analyst
Friday, December 9, 2016 3:39PM CST
Friday, December 2, 2016 3:33PM CST
Wednesday, November 23, 2016 1:10PM CST
South America Calling
Alastair Stewart
South America Correspondent
Thursday, December 8, 2016 6:48AM CST
Monday, November 14, 2016 3:53PM CST
Monday, November 7, 2016 1:16PM CST
An Urban’s Rural View
Urban Lehner
Editor Emeritus
Thursday, December 8, 2016 9:04AM CST
Thursday, December 1, 2016 11:05AM CST
Monday, November 21, 2016 6:18PM CST
Machinery Chatter
Jim Patrico
Progressive Farmer Senior Editor
Wednesday, November 30, 2016 4:20PM CST
Monday, November 21, 2016 12:21PM CST
Wednesday, November 16, 2016 5:06PM CST
Canadian Markets
Cliff Jamieson
Canadian Grains Analyst
Friday, December 9, 2016 3:50PM CST
Thursday, December 8, 2016 4:46PM CST
Tuesday, December 6, 2016 2:06PM CST
Editor’s Notebook
Greg D. Horstmeier
DTN Editor-in-Chief
Monday, November 21, 2016 4:29PM CST
Tuesday, November 8, 2016 9:46AM CST
Monday, October 3, 2016 4:25PM CST
Copyright DTN. All rights reserved. Disclaimer.
Powered By DTN