Weed Management

The purpose of this course is to give the reader an overview of key practices that can help avoid or delay selecting for herbicide-resistant weeds and pesticide-resistant pests while managing weeds and pests in the field, particularly for cotton growers.

Weeds are defined as any plants that “interfere with the growing of crops or ornamental plants; endanger livestock; affect the health of people; interfere with the safety or use of roads, utilities, and waterways; or are visual or physical nuisances." Weeds can pose fire hazards and exacerbate allergies. They can clog canals, harbor insect pests, and poison people and animals.

The purpose of this training is to give you an overview of important management practices that can help avoid or delay the development of herbicide-resistant weeds. We will begin with a brief review of common weed types and herbicides, followed by factors that can influence the evolution of resistance in weeds, and methods for potentially delaying its occurrence in agronomic row crops and permanent crops. While weed resistance management guidelines may be introduced and discussed under a specific annual or perennial crop heading, many of the WRM techniques have cross-crop applicability. When using pesticides for resistance management, always check the label for specific registered uses and the Herbicide Group Number for Mode of Action (MOA), as well as contact your local University Extension Advisor, PCA, and/or manufacture representative.

In production agriculture, weeds or “misplaced plants” have a tendency to tolerate suboptimal conditions much better than most crops. However, they grow more and produce more seed under optimal conditions than they do under suboptimal. For example a nine-foot tall horseweed growing in a vineyard produces 800,000 seeds while a foot tall horseweed growing on a dry, hard road shoulder produces only about 1,000 seeds. Weeds are unwanted plants that compete with crops for nutrients, light and water, and can be detrimental to crop yields. Integrated weed management (IWM) programs and orchard cultural practices have been developed for specific orchard and vineyard crops. This accredited CEU provides information on economically and environmentally sound IWM practices. This course will provide an overview of important weed control and management practices as well as some insight into managing for herbicide-resistant weeds.

GM alfalfa has been back on the market for about six years, after a detour through the courts that began not long after it was first introduced in 2005 as the fifth glyphosate-resistant crop to be commercialized.

Western Farm Press is pleased to sponsor this course on ant control, which is an important element of harvesting a high quality almond crop. More than 800,000 acres in the San Joaquin and Sacramento valleys are under almond cultivation. Almonds are the largest U.S. specialty export crop and the top agricultural export of the state of California. Protecting this highly valuable crop is a high priority each year. This course focuses on ant management and broadleaf weed control in California almonds. The two subjects are combined because they work together when it comes to protecting newly harvested almonds from ant damage. Ants feed on ground cover and in order to control ants, a grower and/or his PCA must create an environment where ants can be drawn to ant bait.