. Insect and disease conditions in the United States, 1979-83 : what else is growing in our forests?. Forest insects United States; Trees Diseases and pests United States; Plants Disease and pest resistance. F-705648. Figure 2. Sur- rounded by viscin, a mistletoe seed is lodged on a needle. Figure 3. At the base of a needle, an embedded mistletoe seed begins germinating. F-705649 shaping these forests. Fires changed forest composition and sanitized infested stands by kill- ing the parasite when they killed the host tree. The new, replace- ment forests were largely free of mistletoes. Silvicult
. Insect and disease conditions in the United States, 1979-83 : what else is growing in our forests?. Forest insects United States; Trees Diseases and pests United States; Plants Disease and pest resistance. F-705648. Figure 2. Sur- rounded by viscin, a mistletoe seed is lodged on a needle. Figure 3. At the base of a needle, an embedded mistletoe seed begins germinating. F-705649 shaping these forests. Fires changed forest composition and sanitized infested stands by kill- ing the parasite when they killed the host tree. The new, replace- ment forests were largely free of mistletoes. Silvicultural practices to con- trol dwarf mistletoes have been advocated since the early part of the century; however, these efforts were limited to removing only the most infected overstory trees during the course of logging operations. This type of partial cutting actually increased the amount of infection in residual stands. Leaving infected trees of no commercial value in regenera- tion areas also increased the problem. Forest roads and timber mar- kets began improving in the 1950's. Improved access and markets, coupled with more specific guidelines from research, made it possible for managers to take more effective action against the dwarf mistletoes. In the past 10 years, dwarf mistletoe control programs have been more consistent. Most recently (1979-83), an average of $860,000 a year was spent on dwarf mistletoe control. The money was used for pretreatment surveys on 900,000 acres (364,000 ha) and to treat 74,000 acres (30,000 ha). Thousands of addi- tional acres are treated each year through normal stand improve- ment and timber harvesting operations. The Federal Jobs Bill program, started in 1983, also helped accomplish timber stand improvement projects that other- wise would not have been Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may
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