Cotton grows slowly in the spring and can be shaded out easily by weeds. If weeds begin to overpower the seedling cotton, drastic reductions in yield can result. Later in the season, cotton leaves fully shade the ground and suppress mid-to-late season weeds. For these reasons, weed control is focused on providing a 6 to 8-week weed-free period directly following planting.
Producers employ close cultivation and planters that place the cottonseed deep into moist soil, leaving weed seeds in high and dry soil. Herbicides or cultivation controls weeds between the rows.
The cotton plant has evolved with numerous damaging insects. These insects, if left unattended, would virtually eliminate the harvestable crop in most cotton-producing areas. Plants infested with leaf-feeding insects are able to compensate somewhat by producing more leaves. Many of cotton’s insects, however, feed on squares and bolls. This reduces the yield and leads to delays in crop development, often into the frost or rainy season.
The cotton industry utilizes a multifaceted approach to the problem of insects. Known as Integrated Pest Management (IPM), it keeps pests below yield-damaging levels. IPM is dependent on natural populations of beneficial insects to suppress damaging pests. Additionally, some cotton varieties are genetically bred to be less attractive to insects.
Some plants are improved by modern biotechnology, which causes the plant to be resistant to certain damaging worms. Other modern biocontrol strategies also are used. For example, where populations of damaging pink bollworm insects break out, sterile insect releases are used to target the pest and minimize disruption to the beneficial insects. Also, cultural practices that promote earliness and short-season production reduce the vulnerability of cotton production to pests. Plant protection chemicals are often used to prevent devastating crop losses to insects. All plant protection methods used on plants in the U.S. are thoroughly evaluated by the Environmental Protection Agency (EPA) to assure food safety and protection to humans, animals and to the environment.