The lodgepole pine type commonly occurs as an even-aged, singlestoried, and overstocked forest. Dwarf mistletoe is widespread throughout the type and causes growth and quality reduction, reduced seed production, and some direct mortality. The land manager has three alternatives where dwarf mistletoe occurs: (1) do nothing, (2) eradicate the stand,...
Windthrow occurred during late April on the Glacier View, Hungry Horse, Spotted Bear, and Swan Lake Ranger Districts, Flathead National Forest. An evaluation to determine potential for development of spruce beetle and Douglas-fir beetle outbreaks was made during late June and early July. All areas examined were classed as having...
Dipel (R) was applied by helicopter to three blocks of Douglas fir and Engelmann spruce infested with Choristoneura occidentalis Free., in southwestern Montana. Dosage was 1 pound (7.2 Bill) in 2 gallons of water/acre (453 g in 7.5 t/0.4 ha). A commercial surfactant, Bio-film (R) was added at the rate...
Aerial surveys of six Montana National Forests in 1975 found a 22.1% increase in the area of visible defoliation caused by the western spruce budworm. It is estimated that 2,278,804 acres of Douglas-fir forests are now suffering at least 25% defoliation. This is an increase of 503,706 acres over the...
The pine needle cast fungus, Lophodermella concolor, caused severe discoloration and subsequent defoliation of lodgepole pine on over 4,000 acres and light defoliation on over 4,500 acres of lodgepole pine in the lower Clark Fork River drainage in 1975. Some trees had lost the last 3 years' growth of needles,...
Mortality from various causes was recorded in a Douglas-fir tussock moth, Orgyia pseudotsugata McD., outbreak southeast of Coeur d'Alene, Idaho, in 1974. Observations began June 27 when about 50 percent of the larvae were second instars and continued until pupation. Within a 35-day period, there was a 93 percent average...
Emerged beetles were first collected July 17 and peak emergence occurred between August 10 and 26, 1975. Density of attacks averaged four per 0.5 ft. 2 (0.05 m2). Parent to brood ratio was 1:4.6. Thirteen associate insects, representing six families of Coleoptera and one of Diptera, were recovered. Associates included...
Mountain pine beetle reached epidemic levels in the Lap, Cool, Lang, and Caribou Creek drainages in 1974. From 1973 to 1975, approximately 56,282 trees with an estimated volume of 4,365,660 board feet were killed in these areas. An additional 61,721 trees are predicted to be killed in 1976. Currently infested...
Mountain pine beetle has occurred at epidemic level in lodgepole pine stands in the west Gallatin River drainage since 1969. Infestation now encompasses about 5,500 acres. Since 1969, approximately 463,212 trees, with an estimated volume of 20,529,244 board feet have been killed. Approximately 69 percent of the stands on the...
Evaluation of four 35 mm film:lens combinations for estimating conifer mortality showed that large-scale true color images obtained with Kodak High Speed Ektachrome and color infrared images obtained with Kodak Ektachrome Infrared, both exposed through a 135 mm lens were best. Higher correlation coefficients were found for the true color:135...
Mountain pine beetle infestations in the Snell Creek and Warland Peak areas were evaluated in October 1975. Based on current buildup ratios, tree diameter distributions, stand composition and phloem thicknesses, there appears to be limited opportunity for epidemic potential in either area. Management alternatives are discussed. Selective logging is recommended...
Shade tree insect and disease activity within the city limits of Bozeman, Montana, were evaluated. Other than a few minor insects, the park, cemetery, and street trees are in remarkably good condition. Both the Park Department and private homeowners appreciate the value of trees in the urban environment. Recommendations on...
A supplemental Douglas-fir tussock moth egg mass evaluation was made within three quarter sections north of Poison, Montana, during April 1975. These areas were being considered for a pilot control project of a nucleopolyhedrosis virus spray. Results from the April evaluation showed these areas no longer qualified as sites for...
Mountain pine beetle reached epidemic levels in the Lazier-Meadow Creek drainages on mixed ownership in 1972. A total of 118,486 trees with an estimated volume of 5,666,124 board feet was killed from 1972 through 1974. Presence of overstocked, mature, nearly pure lodgepole stands, coupled with favorable weather conditions, are believed...
The benomyl fungicide, rersan, applied at 7 and 14 pounds active ingredient per acre, on April 26 and July 25, 1973, was ineffective in reducing mortality in 2-0 Engelmann spruce seedlings derived from two different seed sources growing in three different nursery sections at the USFS Coeur d'Alene Nursery. Percent...
Two concentrations of dimethoate were applied with a hydraulic ground sprayer to cone-bearing Douglas-fir and grand fir trees. Single application (mid-June) and a double application (mid-June and mid-July) were compared. Three of the four treatments applied to Douglas-fir resulted in a significantly higher number of sound seeds produced per cone...
Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., has caused extensive tree mortality in the North Fork Clearwater River drainage since 1971. In 1974, survey estimates indicated a continued decline in the infestation. Average group size decreased from a high of 158 trees per group in 1971 to 17 in 1974. Average area...
Mountain pine beetle populations reached epidemic levels on approximately 4,600 acres in Glacier National Park in 1972. Infested trees increased from 4.9 in 1972 to 10.9/acre in 1975. Majority of trees killed since 1972 were 12 inches d.b.h. and larger in size. Sufficient large diameter lodgepole pine exists to maintain...
Evaluation of Douglas-fir tussock moth, Orgyia pseudotsugata, egg masses collected from an outbreak area in the lower Flathead Valley indicated that overall egg viability was relatively high, egg parasitism was low, and virus infestation averaged 7.1 percent northwest of Polson, 17.9 percent south of St. Ignatius, and 57.0 percent west...
The mountain pine beetle, Dendroctonus ponderosae Hopk., infestation in Yellowstone National Park advanced north and eastward in 1974. New infestation centers were located along the east shore of Yellowstone Lake and south of the Promontory to the Park's southern boundary. Ground surveys indicated an average of 2.9 infested trees per...
Mountain pine beetle populations reached epidemic levels in 1972 in the Stoney Creek drainage, Ninemile District, Lolo National Forest, Montana. A total of 8,082 trees with an estimated volume loss of 34,356 board feet has occurred from 1972 to 1974. Buildup ratio was 1:1.2 from 1972 to 1973, and 1:1.8...
The mountain pine beetle infestation has been epidemic in lodgepole pine in Yellowstone National Park since 1966. Infestation boundaries have advanced steadily northward and eastward. The infestation now encompasses nearly one-half of the total Park area. Surveys indicate a decline in tree mortality the last 2 years. In 1970, an...
Aerially visible defoliation by the western spruce budworm, Choristoneura occidentalis Freeman, increased from 149,250 acres in 1973 to 649,319 acres in 1974 on five eastern Montana National Forests. An egg mass survey during the fall of 1974 predicted that additional defoliation will occur in 1975 on 47 of 48 plots...
A study was conducted in summer of 1973 to assess impact of fluoride-insect damage on radial growth of lodgepole pine near the Anaconda Aluminum Company at Columbia Falls, Montana. Statistically significant growth losses attributed primarily to the effects of fluorides were found in 40 14 of 17 unmanaged stands for...
Dwarf mistletoes exert an impact on forest productivity, but this impact can be reduced through management practices. Even infested stands can yield considerable volumes if proper control methods are used. Projections of future yield increases due to control efforts are made. Cost of treatment in fiscal year 1973 was $51...