Weeds

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.…

The 2015 University of Illinois Weed Science Field Day will be held next Wednesday, June 24th at the University of Illinois Crop Sciences Research and Education Center, located immediately south of the main campus. Coffee and refreshments will be available under the shade trees near the Seed House beginning at 8:00 a.m.
Similar to past years, we will car pool to the fields where participants can join in a guided (but informal) tour format. The tour will provide ample opportunity to look at research plots and interact with weed science faculty,…

The Department of Crop Sciences will host International Agronomy Day on August 31, 2015 at the Crop Sciences Research and Education Center at the University of Illinois. We have developed International Agronomy Day as an opportunity for international visitors to attend a field tour at the University of Illinois and interact with many of our faculty and staff.  International Agronomy Day will take place the day before the Farm Progress Show opens in Decatur to provide an opportunity for international visitors traveling to the United States to attend the Farm Progress Show to learn more about the research being conducted by our faculty and staff.…

Palmer amaranth continued to expand its presence in Illinois during 2014. Palmer amaranth populations have been confirmed in counties colored orange or blue in Figure 1; orange designates glyphosate-resistant populations are present in these counties. It should be neither construed nor assumed that Palmer amaranth populations occur only in the counties colored on this map. It is altogether likely that Palmer amaranth populations are present in many other counties. Emerged Palmer amaranth plants were observed on May 7 at our field research location west of Kankakee.…

A scouting trip last Thursday to our Palmer amaranth research location west of Kankakee revealed that Palmer amaranth plants had begun to emerge a few days before our arrival. Early and accurate identification of Palmer amaranth plants is an important component of an integrated management program, but differentiating among seedling-stage Amaranthus plants sometimes can be difficult. As plants become larger and reproductive structures are present, identification becomes increasingly easier. The following photographs might help renew your Amaranthus species identification skills.…