Changes in the Weed Species Composition of the Southern United States: 1974 to 1995

摘要

The Southern weed Science Society has conducted an annual survey of the most trou- blesome weeds in several major crops since 1971. The objective of this summary was to charac- terize shifts in weed populations over a 22-yr period in four major agronomic crops. For corn, soybean, cotton, and peanut, the largest increases in rank as the most troublesome weeds were found with sicklepod and bermudagrass. The largest decreases were found with johnsongrass, crab- grasses, and common cocklebur. Morningglories and nutsedges remained relatively constant weed problems over the 22-yr period.