Crops that have been genetically modified (GM) to be tolerant to herbicides have been widely grown in the USA since 1996. The rapid and widespread adoption of this technology reflects the important economic and environmental benefits that farmers have derived from its use (equal to $21.7 billion additional farm income and a 225 million kg reduction in herbicide active ingredient use 1996-2012)....

Herbicides are the most efficient and cost-effective means of weed management [...]

Weeds are a major pest that reduce aesthetics and functionality of turfgrass systems. Knowledge required for effective weed management has evolved in recent years as weeds develop resistance to herbicides, government restriction broad-spectrum herbicides increased, registration new herbicide active ingredients slowed. This chapter discusses relevant developments synthetic alternatives non-chemi...

In low-input land-use systems combining timber trees with shade-tolerant understorey crops, it is essential to establish the effects of tree density upon weeds and the contribution of weeds to competition and nutrient cycling. Adjusting tree density may alter weed competition for light, water and nutrients, the storage of nutrients by weeds through growth and the release of nutrients via decomp...