- Author: Lynn M. Sosnoskie
- Author: Konrad Mathesius
Italian ryegrass (Lolium multiflorum) is an annual grass that can sometimes behave as a biennial or short-lived perennial in California. The species is upright in habit (to about 3 feet in height); seeds germinate in the late fall and the plants grow vigorously through the winter and early spring. Ryegrass can be identified by its dark green, glossy and hairless leaves that are rolled in the bud. Auricles are well-developed and the ligules are long and membranous. Once flowering occurs, ryegrass is easily distinguishable by alternating spikelets that run along the length of the main flowering stem (April through September). Additional photos can be found at the end of this post; more details regarding Italian ryegrass...
- Author: Lynn M. Sosnoskie
Weeds compete with crops for light, water, and nutrients, which can result in yield reductions. Weeds can also interfere with crop production by serving as alternate hosts for pests and pathogens, providing habitat for rodents, and impeding harvest operations among other impacts. Natural areas can also be impacted by weed species when they reduce aesthetics, cause physical harm, and disrupt ecosystem services. As a consequence, growers and land managers employ a variety of control strategies, including the application of herbicides, to manage unwanted vegetation.
Although herbicides can be extremely effective at controlling undesirable plants, failures can and do occur. Weeds may escape chemical treatments for several reasons...
- Author: Lynn M. Sosnoskie
The first step in developing an effective weed management program is being able to properly identify the weed species that are infesting a field. But why? Why is weed identification so important? Simply stated, because not all weeds are created equal. Species differ with respect to their emergence timing, life history traits, competitive interactions with the crop, potential to harm livestock, and sensitivity to available herbicides, among other characteristics. Consequently, the type and timing of weed control events need to be designed to target problematic species so that control is maximized, weed seed return to the soil seedbank is minimized, and crop yields are protected.
Unfortunately, weed identification is not a simple...
- Author: Lynn M. Sosnoskie
Glyphosate was commercialized in 1974. Since then, it has become one of the most widely used and studied herbicides. According to Duke (2018b), almost 20,000 scientific publications and patents have included glyphosate as a focus; only 2,4-D surpasses it with respect to citations. The articles in the 5th issue of the 74th volume of Pest Management Science are no different; they all focus on this important (and controversial) molecule.This special issue arose from a day long symposium organized by Stephen O. Duke (University of Mississippi) and Keith Solomon (University of Guelph) that was held at the 252nd annual meeting of the American Chemical Society (Duke 2018a).
