Many IPM programs have been astonishingly successful. After years of heavy pesticide use had only worsened the brown plant hopper problem in rice fields, the Indonesian government in 1986 banned dozens of insecticides and invested millions of dollars in IPM training for farmers. In the next four years, the countrys pesticide use fell 50 percent, rice yields rose 12 percent and the brown plant hopper problem faded away. In the Rio Grande Valley of Texas, IPM has allowed cotton farmers to go from 12 sprayings per year to just four. Besides reducing risks to wildlife or human health, such efforts carry a less obvious benefit: resistance develops more slowly when pests are zapped less often.
Fed by success stories like these, interest in IPM programs is gradually spreading throughout mainstream American agriculture. Farm organizations, environmentalists and even chemical companies have joined forces to push for wider use of IPM, though a few critics charge that some of this support is little more than lip service to justify continued reliance on pesticides. In the governmental ranks, the U. S. Department of Agriculture and the Environmental Protection Agency not previously the most cordial of partners on pesticide issues, according to IPM program coordinator Michael Fitzner of the USDA Extension Service have begun cooperating on IPM research and policy.
Nevertheless, IPM has been slow to appear in farmers fields. Although it has become the norm for a few crops such as cotton, citrus, apples and tomatoes only about a quarter of high-acreage field crops like corn, wheat and soybeans have made the transition. Most experts blame a shortage of IPM specialists and a lack of funds for educating farmers in the new techniques. In addition, economic constraints often hinder the switch to IPM. In northeastern states, for example, many growers say they cant afford to rotate potatoes with crops like soybeans or wheat an effective way to control potato beetles because land rents are too high to make these lower-grossing crops profitable.
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