In addition to herbicides, what weed control methods do growers use?
Most farmers in developing countries have relied primarily on hand weeding and hoeing. Labor costs and average farm sizes make manual weed control impossible for most U.S. growers. For example, in the early 1990s the cost of manual weed control for lettuce growers in Florida was $200/acre, compared to an average cost of $15-20/acre for herbicides at that time. Manual weed control is being used less often in developing countries, because laborers are leaving rural areas for better paying jobs in urban areas. Other weed control techniques U.S. growers use on a regular basis are cultivation, crop rotation, cover crops, mowing, mulching, planting geometry and planting time to give crops the competitive edge over weeds. In a few instances, biocontrol agents, such as plant pathogens and insect herbivores are used to manage weeds.
