Weeds

Marestail can be one of the most challenging weeds to control prior to planting no-till soybean.  Already this season some have reported poor marestail control following applications of glyphosate plus 2,4-D.  Poor control can be caused by several factors, including large plant size and resistance to glyphosate.  If a marestail population is resistant to glyphosate, a pint of 2,4-D in the spring is generally inconsistent/ineffective when it’s the only product in a tankmix active on the resistant population.…

The following information about cover crop termination is taken from the 2016 Weed Control Guide for Ohio, Indiana and Illinois.  The information was originally written by extension weed scientists at Purdue University.
Cover crops are unique in that most are planted primarily to reduce soil erosion and otherwise enhance soil quality, and are not harvested for their seed, fruit, or forage (although some are grazed or used as forage). Instead, cover crops are terminated before planting of summer annual grain crops such as soybeans and corn.…

On February 3, Monsanto announced its commercial launch plans for soybean varieties resistant to the herbicides dicamba and glyphosate (designated Roundup Ready 2 Xtend varieties). This announcement followed China’s decision to import grain from these varieties. Many weed management practitioners hope this new technology package will provided improved control of problematic weed populations, including those with evolved resistance to glyphosate and herbicides from other site-of-action families. The weed science program at the University of Illinois has evaluated this technology for several years,…

The 2016 Weed Control Guide for Ohio, Indiana and Illinois contains 224 pages of weed management information, including weed response ratings for corn and soybean herbicides. Information and recommendations for managing weeds in small grains and forages is included, along with more specific information about and control recommendations for several problem weed species. A pdf of the 2016 Weed Control Guide is available to download, and a printed version of the guide can be ordered at: http://estore.osu-extension.org/2016-Ohio-Indiana-and-Illinois-Weed-Control-Guide-P433.aspx
 …

Here is the final installment of considerations for weed management in 2016.
 
Steps for Successful Weed Management in Glufosinate-Resistant (Liberty Link) Soybean
 
Step 1:
Plant Liberty Link soybean seed into a weed-free seedbed
Achieve a weed-free seedbed through the use of:
                          1) Preplant tillage
                          2) Effective burndown herbicide(s)
                          3) A combination of tillage and burndown herbicides
 
Step 2:
Select and apply within 14 days of planting a soil-residual herbicide that targets your most problematic weed species.…

 
Here is the third installment with additional considerations for weed management in 2016.  The final installment will be posted tomorrow.
 
Multiple or Effective
The continuing and expanding challenges imposed on agronomic cropping systems by weed populations resistant to various herbicides has led to renewed interest in utilizing multiple modes of herbicide action in weed management programs. Indeed, articles written about and advertisements for products that contain multiple modes of action populate many farm media publications.…

Here is the second installment with additional considerations for weed management in 2016.
Resistance remains
Herbicide-resistant weed populations continue to be a common occurrence across most areas of Illinois. Waterhemp and horseweed (marestail) are the two most common herbicide-resistant weed species in Illinois, and observations during 2015 suggest these species are likely to remain prevalent in 2016. Approximately 1700 waterhemp samples (representing 338 fields) were submitted to the University of Illinois Plant Clinic in 2015 for herbicide resistance screening.…

One of the founding fathers of the United States is often credited as the source of the phrase “in this world nothing can be certain, except death and taxes.” Scholars and pundits alike have added other “certainties” to this relatively short original list, so perhaps we can enjoy a sense of serenity to suggest another: weeds. Even with all the time and resources expended to control weeds in 2015, one can be reasonably confident this persistent foe will again plague Illinois fields in 2016.…

In early 1998, Extension specialists in the Department of Crop Sciences (Drs. Kevin Steffey, Mike Gray, Bob Hoeft, and Emerson Nafziger) launched a new educational program dubbed the Corn & Soybean Classic. The program consisted of a series of regional meetings at which extension specialists shared with those in attendance the most current and relevant information related to crop production, pest management, and farm economics. Annually for 18 years, 7 to 10 specialists spent many long hours compiling the information generated from applied and basic research programs into a format that was shared with an audience that ranged in size from 800 to over 1300.…