The USDA Animal Plant and Health Inspection Service (APHIS) is seeking review and comment from the public on the possibility of deregulating corn and soybean seed that’s resistant to 2,4-D, among other herbicides....More
Corn and soybean farmers test-drove several new herbicides over the rugged proving ground of the 2013 growing season. The new active ingredient pyroxasulfone appears in three new products: Zidua, Anthem and Fierce.
Consider a three-way look at your crop — from above and below and at ground level. That means a close-up look at plant roots and soil for clues to plant growth, plus aerial images to detect, confirm and define a problem....More
An important component of managing weeds in field crops is preventing the seeds released by weeds each autumn from becoming new plants. Nature assists in the loss of weed seed through predation, decay and loss of viability. Integrated weed management strategies that facilitate these processes can lead to high levels of weed seed loss....More
More adverse spring weather and the northern spread of herbicide-resistant marestail find more reduced-tillage farmers considering fall residual herbicide applications. “Fall applications have risen dramatically in the last few years and will continue to grow,” says Regan Wear, CHS agronomy manager in Shipman, Ill. “Erratic, wet, cold springs have narrowed the planting window and fueled interest in fall residual herbicide applications because they really sharpen up timing the following spring.”...More
You plan years ahead for crop rotation, fertilizer and machinery acquisitions. Since the rise of glyphosate-resistant weeds, you should be doing the same for your herbicide program, says Lisa Behnken, a Minnesota Extension crops specialist....More
The University of Illinois Extension has received many questions about applying herbicides post-harvest to control emerged marestail plants. Fall-applied herbicides often provide more effective and consistent control of emerged marestail as compared with spring-applied (i.e., burndown) herbicides, says Aaron Hager, weed specialist with U of IL Extension. Here are tips from the Extension service for fall-applying herbicide to control emerged marestail....More
With corn and soybean harvest underway in all major producing states, farmers are thinking about herbicide applications this fall. Aside from weed management, there are other factors to be considered when applying herbicide after harvest including: spring weather uncertainty, impact on soil conditions, pest interactions....More
Before you run that combine through every acre of your fields, I’d highly recommend reading “Resistant Palmer amaranth hits the Midwest." This weed is a game changer, and if left unchecked without multiple herbicide modes of control, you can literally lose a field in three years’ time....More
On July 6, 2011, Joe Steinkamp changed his entire weed-management program. Steinkamp raises seed soybeans and white corn on Ohio River bottomland near Evansville, Ind. On that July day two years ago, his neighbor brought over some weeds that had survived Roundup. “He said, ‘Joe, do you know that these are?’ I said, ‘I sure do!’ ”...More
Recently, populations of Palmer amaranth have been identified in several Illinois counties. The density of many populations is relatively low, and often these plants occur only in small patches. However, a few scattered plants this year can lead to severe infestations within only a few years....More
Recently there have been several inquiries about the presence of glyphosate-resistant volunteer soybeans in corn fields and cost-effective control options. These volunteers emerge from seed that shattered before soybean harvest or fell during combining. Historically, soybeans are not considered a serious volunteer weed problem in corn because they are not very competitive and several herbicide options are available to control them in corn....More
When weeds become resistant to herbicides, the advantage of growing herbicide-resistant crops is lost. Farming practices that limit the emergence of resistant weeds offer another means of control and thwart weeds’ effect on soybean crop production. Finding the right combinations of weed control methods can improve yields and reduce dependence on chemical weed control....More
Early-season weed competition resulted in as much as 40-bu./acre yield loss according to data found in some South Dakota State University Research Plots. "Everyone knows that weeds in fields create competition for water and nutrients and can cause significant yield loss, but many neglect the effects of just early-season weeds on crop yield," says Mark Rosenberg South Dakota State University agronomy and weeds field specialist....More
It’s another post-emergence application (post) soybean season, and we have largely been receiving questions similar to the past several years. These include how to manage giant ragweed, pokeweed and a few other perennials, vines and marestail (good luck there)....More
The weed science program at the University of Illinois is offering free screenings for herbicide resistance in waterhemp to Illinois farmers during the 2013 growing season. Aaron Hager, associate professor of weed sciences at U of I, says with continued financial support from the Illinois Soybean Association, over 1,000 plant samples have been screened through the collaborative effort between the U of I and the ISA....More
After starting the season with clean fields at planting, now is the time to focus on early-season weed control to maintain maximum yield potential. For corn, weeds can reduce yield as soon as the V2 stage or when corn is roughly 6-8 in. tall....More
Early and accurate identification of Palmer amaranth plants, including waterhemp, coupled with implementation of an integrated management program are essential to reduce the potential for crop yield loss due to interference of Palmer amaranth. Proper management of Palmer amaranth populations can help reduce the potential for successful seed production that will augment the soil seedbank and perpetuate the population in future growing seasons.
Over the past several days, growers have increasingly been looking for options to control marestail after corn and soybean emergence, says University of Illinois Associate Professor of Weed Sciences Aaron Hager. “Many have reported poor marestail control from herbicides applied prior to planting (primarily no-till soybean), especially when these burndown applications contained only glyphosate or glyphosate and 2,4-D."...More
With very tight windows of opportunity to plant this year, pre-emergence herbicides may not have been applied as planned. Application of a residual herbicide prior to planting or emergence of the crop, in both corn and soybean, is a great weed management strategy overall and also a key tool in managing against herbicide resistance. What are some options if soybeans emerged before a pre-emergence herbicide application was made?...More
The increasing prevalence of waterhemp plants and populations that demonstrate resistance to herbicides from more than one site-of-action family increases the importance of controlling any emerged waterhemp plants before planting....More
One of the problems with a wet start to the season when planting gets compressed into short periods is the lack of time to apply preemergence herbicides and 28% before corn emerges. Most pre-emergence corn herbicides can be applied to emerged corn, and some of them have enough foliar activity to control small, emerged weeds without the need to add postemergence (post) herbicides....More
With more weeds becoming glyphosate-resistant or surviving glyphosate-only applications, corn growers continue to rely on residual herbicides to manage tough weeds and protect their yield. "We need to maximize the number of sites of action,” says Travis Legleiter, weed program science specialist at Purdue University.
Wet soil conditions have caused delays in planting and in efforts to control existing weed vegetation. Much of the existing weed growth is comprised of winter annual species, such as common chickweed, henbit, purple deadnettle, etc., but emergence of several summer annual species also has begun....More