Good management models for postemergence weed control require good estimates of which weed density produces an economic threshold yield. Because intraweed competition increases if weeds are aggregated, weed spatial pattern may be an important factor for inclusion in management models. Mathematical models of weed–crop competition have demonstrated that this may be the case, but the small number ...

In modern agriculture, with more emphasis on high input systems, weed problems are likely to increase and become more complex. With heightened awareness of adverse effects of herbicide residues on human health and environment and the evolution of herbicide-resistant weed biotypes, a significant focus within weed science has now shifted to the development of eco-friendly technologies with reduce...

Weed emergence timing: a new tool for managing weeds in crop fi elds The success of integrated weed management relies on matching control strategies to the specifi c weed problem in a fi eld. Managers must know not only which weed species (and how many) are present in a fi eld; they also must understand the distribution and development stages of these weeds throughout the fi eld. Weed control r...

Weed infestations and associated yield losses require effective weed control measures in soybean and sugar beet. Besides chemical weed control, mechanical weeding plays an important role in integrated weed management systems. Field experiments were conducted at three locations for soybean in 2013 and 2014 and at four locations for sugar beet in 2014 to investigate if automatic steering technolo...

Parthenium hysterophorus L. (congress grass, congress weed, carrot weed, wild feverfew, the “Scourge of India”) is an exotic weed that was accidentally introduced in India in 1956 through imported food grains.[1] It has become a common weed causing dermatitis of epidemic proportions.[2] The epithet “congress weed” refers to the US congress (who allocated the shipment for Pune, India).[3] In Pun...

Martin M. Williams II Corresponding author. U.S. Department of Agriculture—Agricultural Research Service, Invasive Weed Management Research, University of Illinois, 1102 S. Goodwin Ave., Urbana, IL 61801; [email protected] The critical period for weed control (CPWC) identifies the phase of the crop growth cycle when weed interference results in unacceptable yield losses; however, the effect of ...

Weed control through crop rotation has mainly been studied in a nonspatial context. However, weed seeds are often spread beyond the crop field by a variety of vectors. For weed control to be successful, weed management should thus be evaluated at the landscape level. In this paper we assess how seed dispersal affects the interactions between crop rotation and landscape heterogeneity schemes wit...