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• 181. [Article] Status of mountain pine beetle infestations, Glacier National Park and Glacier View Ranger District, Flathead National Forest, Montana, 1977

  Mountain pine beetle populations developed to epidemic level in Glacier National Park in 1972. Buildup ratio of old to newly attacked trees was 1:1.8 from 1976 to 1977. More than 12 million trees are infested ...

  Citation × Citation Citation Abstract Copy Title: Status of mountain pine beetle infestations, Glacier National Park and Glacier View Ranger District, Flathead National Forest, Montana, 1977 Author: McGregor, Mark D., Hamel, Dennis R., United States. Forest Service. Northern Region. State & Private Forestry, Kohler, Scott Mountain pine beetle populations developed to epidemic level in Glacier National Park in 1972. Buildup ratio of old to newly attacked trees was 1:1.8 from 1976 to 1977. More than 12 million trees are infested on 142,871 acres. Buildup ratio is expected to exceed 1:3 from 1977 to 1978. Management with fire is recommended to reduce potential hazard and to create a mosaic of young stands within the extensive areas of large timber. In high use areas, all green lodgepole pine 7 inches d.b.h. and larger which are to be retained should be treated with the protective spray Sevimol-4®. Hazard trees should be removed. More than 1.5 million trees are infested on about 27,000 acres on the Glacier View Ranger District. Buildup ratio from 1976 to 1977 exceeded 1:5, and is expected to exceed 1:5 from 1977 to 1978. An accelerated program of logging infested and high risk trees is recommended for high hazard stands. Silvicultural methods for management of various stands are discussed. Title: Status of mountain pine beetle infestations, Glacier National Park and Glacier View Ranger District, Flathead National Forest, Montana, 1977 Author: McGregor, Mark D., Hamel, Dennis R., United States. Forest Service. Northern Region. State & Private Forestry, Kohler, Scott Mountain pine beetle populations developed to epidemic level in Glacier National Park in 1972. Buildup ratio of old to newly attacked trees was 1:1.8 from 1976 to 1977. More than 12 million trees are infested on 142,871 acres. Buildup ratio is expected to exceed 1:3 from 1977 to 1978. Management with fire is recommended to reduce potential hazard and to create a mosaic of young stands within the extensive areas of large timber. In high use areas, all green lodgepole pine 7 inches d.b.h. and larger which are to be retained should be treated with the protective spray Sevimol-4®. Hazard trees should be removed. More than 1.5 million trees are infested on about 27,000 acres on the Glacier View Ranger District. Buildup ratio from 1976 to 1977 exceeded 1:5, and is expected to exceed 1:5 from 1977 to 1978. An accelerated program of logging infested and high risk trees is recommended for high hazard stands. Silvicultural methods for management of various stands are discussed. Close

• 182. [Article] Reevaluation of larch casebearer parasites in casebearer-infested stands of Region I

  The larch casebearer, Coleophora laricella (Hubner) was first reported attacking western larch, Larix occidentalis, in Idaho in 1957 (Denton, 1958), 71 years after its introduction into Massachusetts from ...

  Citation × Citation Citation Abstract Copy Title: Reevaluation of larch casebearer parasites in casebearer-infested stands of Region I Author: United States. Forest Service. Northern Region. State & Private Forestry, Flavell, Thomas H. The larch casebearer, Coleophora laricella (Hubner) was first reported attacking western larch, Larix occidentalis, in Idaho in 1957 (Denton, 1958), 71 years after its introduction into Massachusetts from Europe. The apparent successful regulation of this insect in the eastern U.S. by introduced parasites prompted biological control attempts in the West. Introduction of Agathis pumila (Ratzeburg), considered one of the most significant parasites in the East, was emphasized following a period of laboratory and field evaluations. Between 1966 and 1969, Forest Insect & Disease Management released A. pumila at 378 locations in Washington, Idaho, and Montana. Most releases consisted of attaching parasitized casebearer-infested branches to lower branches of three infested trees at each release location. Evaluations made between 1967 and 1972 verified the presence of A. pumila on 127 plots out of 270 examined and percent parasitism ranged from 0.1 to 90 percent. Title: Reevaluation of larch casebearer parasites in casebearer-infested stands of Region I Author: United States. Forest Service. Northern Region. State & Private Forestry, Flavell, Thomas H. The larch casebearer, Coleophora laricella (Hubner) was first reported attacking western larch, Larix occidentalis, in Idaho in 1957 (Denton, 1958), 71 years after its introduction into Massachusetts from Europe. The apparent successful regulation of this insect in the eastern U.S. by introduced parasites prompted biological control attempts in the West. Introduction of Agathis pumila (Ratzeburg), considered one of the most significant parasites in the East, was emphasized following a period of laboratory and field evaluations. Between 1966 and 1969, Forest Insect & Disease Management released A. pumila at 378 locations in Washington, Idaho, and Montana. Most releases consisted of attaching parasitized casebearer-infested branches to lower branches of three infested trees at each release location. Evaluations made between 1967 and 1972 verified the presence of A. pumila on 127 plots out of 270 examined and percent parasitism ranged from 0.1 to 90 percent. Close

• 183. [Article] Western spruce budworm defoliation trend relative to weather in the Northern Region, 1969-1979

  Western spruce budworm defoliated area in the Northern Region has differed significantly across three discrete geographic zones during the past decade. Aerially visible defoliation in northern Idaho increased ...

  Citation × Citation Citation Abstract Copy Title: Western spruce budworm defoliation trend relative to weather in the Northern Region, 1969-1979 Author: United States. Forest Service. Northern Region. State & Private Forestry, Hard, John S., Eder, Robert G., Tunnock, Scott Western spruce budworm defoliated area in the Northern Region has differed significantly across three discrete geographic zones during the past decade. Aerially visible defoliation in northern Idaho increased from 1.7 million acres in 1969 to a high of 2.2 million acres in 1974, and declined to none in 1979. Defoliated area in western Montana increased from 1.8 million acres in 1969 to a high of 2.8 million acres in 1972 and declined to 0.6 million acres in 1979. Conversely, defoliated area in eastern Montana fluctuated at low levels between 0.1 and 0.7 million acres between 1969 and 1974, and then rose to a high of 1.6 million acres in 1979. Analysis of defoliation trend, the ratio of acres defoliated in the current year by acres defoliated the prior year, and weather during budworm larval and pupal periods during the past decade revealed the following relationships: Defoliation trend in all three geographic areas varied (a) directly with mean maximum temperature during May, June, and July of the year before, and (b) inversely with frequency of measurable precipitation during May, June, and July of the year before. Based on warm, dry conditions throughout the Region in 1979, we predict a general increase in budworm populations in the Northern Region in 1980. Title: Western spruce budworm defoliation trend relative to weather in the Northern Region, 1969-1979 Author: United States. Forest Service. Northern Region. State & Private Forestry, Hard, John S., Eder, Robert G., Tunnock, Scott Western spruce budworm defoliated area in the Northern Region has differed significantly across three discrete geographic zones during the past decade. Aerially visible defoliation in northern Idaho increased from 1.7 million acres in 1969 to a high of 2.2 million acres in 1974, and declined to none in 1979. Defoliated area in western Montana increased from 1.8 million acres in 1969 to a high of 2.8 million acres in 1972 and declined to 0.6 million acres in 1979. Conversely, defoliated area in eastern Montana fluctuated at low levels between 0.1 and 0.7 million acres between 1969 and 1974, and then rose to a high of 1.6 million acres in 1979. Analysis of defoliation trend, the ratio of acres defoliated in the current year by acres defoliated the prior year, and weather during budworm larval and pupal periods during the past decade revealed the following relationships: Defoliation trend in all three geographic areas varied (a) directly with mean maximum temperature during May, June, and July of the year before, and (b) inversely with frequency of measurable precipitation during May, June, and July of the year before. Based on warm, dry conditions throughout the Region in 1979, we predict a general increase in budworm populations in the Northern Region in 1980. Close

• 184. [Article] Pathogenicity of Fusarium from forest seedling nurseries on Douglas-fir and ponderosa pine seedlings

  Eighteen isolates of Fusarium comprising four species (F. oxysporum, E. avenaceum, E. acuminatum, and F. sambucinum) isolated from diseased conifer seedlings from nurseries were tested for pathogenicity ...

  Citation × Citation Citation Abstract Copy Title: Pathogenicity of Fusarium from forest seedling nurseries on Douglas-fir and ponderosa pine seedlings Author: United States. Forest Service. Northern Region. State & Private Forestry, James, Robert L. Eighteen isolates of Fusarium comprising four species (F. oxysporum, E. avenaceum, E. acuminatum, and F. sambucinum) isolated from diseased conifer seedlings from nurseries were tested for pathogenicity on Douglas-fir germlings. Three of the most pathogenic F. oxysporum isolates on Douglas-fir germlings were also tested on ponderosa pine germlings and older Douglas-fir seedlings; three of the most pathogenic F. gamPucinum isolates on Douglas-fir germlings were likewise tested on older Douglas-fir seedlings. Most F. oxysporum isolates and all the other fusaria were highly pathogenic to germlings. Level of virulence on germlings was best measured by rate of infection and tissue degradation. All inoculated older Douglas-fir seedlings became infected, although foliar disease symptoms were rare. Based on extent of root system colonization, isolates of F. oxysporum were generally more pathogenic to older Douglas-fir seedlings than F. sambucinum. These tests confirm the wide range of pathogenicity of fusaria commonly isolated from diseased seedlings. Title: Pathogenicity of Fusarium from forest seedling nurseries on Douglas-fir and ponderosa pine seedlings Author: United States. Forest Service. Northern Region. State & Private Forestry, James, Robert L. Eighteen isolates of Fusarium comprising four species (F. oxysporum, E. avenaceum, E. acuminatum, and F. sambucinum) isolated from diseased conifer seedlings from nurseries were tested for pathogenicity on Douglas-fir germlings. Three of the most pathogenic F. oxysporum isolates on Douglas-fir germlings were also tested on ponderosa pine germlings and older Douglas-fir seedlings; three of the most pathogenic F. gamPucinum isolates on Douglas-fir germlings were likewise tested on older Douglas-fir seedlings. Most F. oxysporum isolates and all the other fusaria were highly pathogenic to germlings. Level of virulence on germlings was best measured by rate of infection and tissue degradation. All inoculated older Douglas-fir seedlings became infected, although foliar disease symptoms were rare. Based on extent of root system colonization, isolates of F. oxysporum were generally more pathogenic to older Douglas-fir seedlings than F. sambucinum. These tests confirm the wide range of pathogenicity of fusaria commonly isolated from diseased seedlings. Close

• 185. [Article] Evaluation of mountain pine beetle in high use areas and other infested stands on the Hebgen Lake Ranger District, Gallatin National Forest, 1977

  Mountain pine beetle populations reached epidemic level on the Hebgen Lake Ranger District in 1970. Infested area increased from 6,680 acres in 1970 to 78,000 acres in 1977. Buildup ratio of trees killed ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of mountain pine beetle in high use areas and other infested stands on the Hebgen Lake Ranger District, Gallatin National Forest, 1977 Author: United States. Forest Service. Northern Region. State & Private Forestry, United States. Forest Service. Northern Region. Forest Insect and Disease Management, McGregor, Mark D. Mountain pine beetle populations reached epidemic level on the Hebgen Lake Ranger District in 1970. Infested area increased from 6,680 acres in 1970 to 78,000 acres in 1977. Buildup ratio of trees killed in 1976 to trees killed in 1977 is 1:8. Approximately 1,700,000 trees, containing 175 MMBF of merchantable timber, are currently infested. An accelerated program of logging infested trees and silvicultural treatment to reduce the inventory of large diameter trees is recommended. In high use areas (campgrounds and administrative sites), 3,027 trees are currently infested. Buildup ratio is expected to exceed 1:1 in 1978. In high use areas all green lodgepole pine 7 inches d.b.h. and larger, which are to be retained, should be sprayed with the protective spray Sevimol 4. Infested trees should be removed prior to July 1, 1978. Trees that have been dead for several years may be a hazard and should be removed. Title: Evaluation of mountain pine beetle in high use areas and other infested stands on the Hebgen Lake Ranger District, Gallatin National Forest, 1977 Author: United States. Forest Service. Northern Region. State & Private Forestry, United States. Forest Service. Northern Region. Forest Insect and Disease Management, McGregor, Mark D. Mountain pine beetle populations reached epidemic level on the Hebgen Lake Ranger District in 1970. Infested area increased from 6,680 acres in 1970 to 78,000 acres in 1977. Buildup ratio of trees killed in 1976 to trees killed in 1977 is 1:8. Approximately 1,700,000 trees, containing 175 MMBF of merchantable timber, are currently infested. An accelerated program of logging infested trees and silvicultural treatment to reduce the inventory of large diameter trees is recommended. In high use areas (campgrounds and administrative sites), 3,027 trees are currently infested. Buildup ratio is expected to exceed 1:1 in 1978. In high use areas all green lodgepole pine 7 inches d.b.h. and larger, which are to be retained, should be sprayed with the protective spray Sevimol 4. Infested trees should be removed prior to July 1, 1978. Trees that have been dead for several years may be a hazard and should be removed. Close

• 186. [Article] Evaluation of multistage sampling techniques to measure lodgepole pine mortality caused by mountain pine beetle in Montana, 1979

  A pilot survey was conducted to evaluate the effectiveness of using multistage sampling techniques to measure annual and cumulative mortality on a State-wide basis with acceptable statistical reliability, ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of multistage sampling techniques to measure lodgepole pine mortality caused by mountain pine beetle in Montana, 1979 Author: United States. Forest Service. Northern Region. State & Private Forestry, Bennett, D. D. A pilot survey was conducted to evaluate the effectiveness of using multistage sampling techniques to measure annual and cumulative mortality on a State-wide basis with acceptable statistical reliability, timeliness, and cost. Within the State of Montana, aerial surveys showed about 986,000 acres of lodgepole pine infested with mountain pine beetle. This area was stratified into three intensity classes. Initial stratification, from 1979 aerial sketchmap surveys, was followed by large-scale (1:6000) aerial photography (on a sample basis), photo interpretation, and ground truth measurements. Photo plots were selected by a systematic random process for each stratum. Ground truth plots were chosen by probability proportional to size (pps). Estimates of 1978 attacked lodgepole pine (faders) were 11.6 million trees, representing a volume of 161.4 million cubic feet. Relative sampling errors were 9.8 and 16.5 percent for numbers of faders and volume, respectively. The total number of standing dead was 33.4 million trees, with a volume of 517 million cubic feet. The survey required 257 man-hours at a cost of $43,500. Title: Evaluation of multistage sampling techniques to measure lodgepole pine mortality caused by mountain pine beetle in Montana, 1979 Author: United States. Forest Service. Northern Region. State & Private Forestry, Bennett, D. D. A pilot survey was conducted to evaluate the effectiveness of using multistage sampling techniques to measure annual and cumulative mortality on a State-wide basis with acceptable statistical reliability, timeliness, and cost. Within the State of Montana, aerial surveys showed about 986,000 acres of lodgepole pine infested with mountain pine beetle. This area was stratified into three intensity classes. Initial stratification, from 1979 aerial sketchmap surveys, was followed by large-scale (1:6000) aerial photography (on a sample basis), photo interpretation, and ground truth measurements. Photo plots were selected by a systematic random process for each stratum. Ground truth plots were chosen by probability proportional to size (pps). Estimates of 1978 attacked lodgepole pine (faders) were 11.6 million trees, representing a volume of 161.4 million cubic feet. Relative sampling errors were 9.8 and 16.5 percent for numbers of faders and volume, respectively. The total number of standing dead was 33.4 million trees, with a volume of 517 million cubic feet. The survey required 257 man-hours at a cost of $43,500. Close

• 187. [Article] The Douglas-fir tussock moth in the Northern Region : a cartographic history of outbreaks from 1928 to 1973

  The Douglas-fir tussock moth, Orgyia pseudotsugata McD., periodically defoliates Douglas-fir, true firs, and other host trees in forests of the western United States. In the Northern Region, these infestations occur ...

  Citation × Citation Citation Abstract Copy Title: The Douglas-fir tussock moth in the Northern Region : a cartographic history of outbreaks from 1928 to 1973 Author: United States. Forest Service. Northern Region. State & Private Forestry, Tunnock, Scott The Douglas-fir tussock moth, Orgyia pseudotsugata McD., periodically defoliates Douglas-fir, true firs, and other host trees in forests of the western United States. In the Northern Region, these infestations occur about once every decade. This history covers the earliest recorded outbreak in northeastern Washington from 1928 to 1930 and includes information about outbreaks in northern Idaho and eastern Washington from 1944 to 1947, northeastern Washington and northern Idaho from 1950 to 1955, northern Idaho and western Montana from 1961 to 1965, and the current outbreak in northern Idaho, northeastern Washington, and western Montana which began in 1970. These outbreaks usually last from 2 to 4 years in forested areas and typically go through a buildup phase the first year, an outbreak phase the second year, and a declining phase the third year due to parasites and/or polyhedrosis virus. Exceptions are: It may take an outbreak 2 years to build up or occasionally natural control agents can cause a population collapse at the end of the second year. Title: The Douglas-fir tussock moth in the Northern Region : a cartographic history of outbreaks from 1928 to 1973 Author: United States. Forest Service. Northern Region. State & Private Forestry, Tunnock, Scott The Douglas-fir tussock moth, Orgyia pseudotsugata McD., periodically defoliates Douglas-fir, true firs, and other host trees in forests of the western United States. In the Northern Region, these infestations occur about once every decade. This history covers the earliest recorded outbreak in northeastern Washington from 1928 to 1930 and includes information about outbreaks in northern Idaho and eastern Washington from 1944 to 1947, northeastern Washington and northern Idaho from 1950 to 1955, northern Idaho and western Montana from 1961 to 1965, and the current outbreak in northern Idaho, northeastern Washington, and western Montana which began in 1970. These outbreaks usually last from 2 to 4 years in forested areas and typically go through a buildup phase the first year, an outbreak phase the second year, and a declining phase the third year due to parasites and/or polyhedrosis virus. Exceptions are: It may take an outbreak 2 years to build up or occasionally natural control agents can cause a population collapse at the end of the second year. Close

• 188. [Article] Evaluation of the Douglas-fir beetle infestation : North Fork Clearwater River drainage, northern Idaho, 1970-73

  An outbreak of Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., 40-4 began in 1969 in the North Fork Clearwater River drainage in northern Idaho. This infestation probably resulted from trees felled ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of the Douglas-fir beetle infestation : North Fork Clearwater River drainage, northern Idaho, 1970-73 Author: United States. Forest Service. Northern Region. State & Private Forestry, McGregor, Mark D. An outbreak of Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., 40-4 began in 1969 in the North Fork Clearwater River drainage in northern Idaho. This infestation probably resulted from trees felled during clearing for the Dworshak Reservoir, from ice and snow breakage which occurred during the winter of 1968-69 in stands adjacent to the proposed reservoir, and an abundance of mature and overmature Douglas-fir within the drainage. The outbreak reached epidemic proportions in 1970, 40 but was not detected until 1971. To determine impact of this insect on Douglas-fir stands within the area of infestation and establish a base from which to conduct salvage logging, a two-stage survey using aerial photography followed by a ground cruise was conducted in 1971, 1972, and 1973. Area surveyed varied from 288,000 acres in 1971 to 494,000 in 1972, and was reduced 410 to 287,000 acres in 1973. The 1971 survey estimated that 174,164 trees were killed during the 2-year period 1970-71, resulting in a volume loss of 85.8 MMBF of Douglas-fir sawtimber on 288,000 acres. In 1972, an estimated 46,844 trees were killed with a volume loss of about 17.8 MMBF on 494,000 acres. In 1973, the survey estimated that 8,141 trees were killed with a volume loss of 4.2 MMIIF of merchantable timber on 287,000 acres. The infestation has been declining since 1971. Title: Evaluation of the Douglas-fir beetle infestation : North Fork Clearwater River drainage, northern Idaho, 1970-73 Author: United States. Forest Service. Northern Region. State & Private Forestry, McGregor, Mark D. An outbreak of Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., 40-4 began in 1969 in the North Fork Clearwater River drainage in northern Idaho. This infestation probably resulted from trees felled during clearing for the Dworshak Reservoir, from ice and snow breakage which occurred during the winter of 1968-69 in stands adjacent to the proposed reservoir, and an abundance of mature and overmature Douglas-fir within the drainage. The outbreak reached epidemic proportions in 1970, 40 but was not detected until 1971. To determine impact of this insect on Douglas-fir stands within the area of infestation and establish a base from which to conduct salvage logging, a two-stage survey using aerial photography followed by a ground cruise was conducted in 1971, 1972, and 1973. Area surveyed varied from 288,000 acres in 1971 to 494,000 in 1972, and was reduced 410 to 287,000 acres in 1973. The 1971 survey estimated that 174,164 trees were killed during the 2-year period 1970-71, resulting in a volume loss of 85.8 MMBF of Douglas-fir sawtimber on 288,000 acres. In 1972, an estimated 46,844 trees were killed with a volume loss of about 17.8 MMBF on 494,000 acres. In 1973, the survey estimated that 8,141 trees were killed with a volume loss of 4.2 MMIIF of merchantable timber on 287,000 acres. The infestation has been declining since 1971. Close

• 189. [Article] Status of mountain pine beetle infestations, Gallatin District, Gallatin National Forest, 1973

  Mountain pine beetle infestations have continued at epidemic level in lodgepole pine stands since 1969 in the West Gallatin River drainage. This infestation has increased at about a 1.9:1 buildup ratio ...

  Citation × Citation Citation Abstract Copy Title: Status of mountain pine beetle infestations, Gallatin District, Gallatin National Forest, 1973 Author: McGregor, Mark D., United States. Forest Service. Northern Region. State & Private Forestry Mountain pine beetle infestations have continued at epidemic level in lodgepole pine stands since 1969 in the West Gallatin River drainage. This infestation has increased at about a 1.9:1 buildup ratio annually. Since the outbreak began in 1969, surveys indicate that approximately 22,354 merchantable size trees have been killed with an estimated volume loss of 1,061 MMBF. This is a total of about 27 percent of the merchantable lodgepole pine within areas surveyed. Additional tree mortality and volume loss have occurred, but not all infested areas were surveyed due to land exchange between Big Sky Corporation, Burlington Northern Railroad, and the Forest Service. Operational control of felling and burning, and salvage logging of infested trees was initiated in 1971. This action did little to slow the impetus of the outbreak, because the complete infestation could not be suppressed. The outbreak is expected to continue at epidemic levels in 1974, with an increase in the number of infested trees. A cooperative administrative study between the Northern Region and Intermountain Forest and Range Experiment Station is planned in fiscal year 1975 to determine if silvicultural methods can be used to control mountain pine beetle in mature and overmature overstocked lodgepole pine stands on the Gallatin National Forest. Title: Status of mountain pine beetle infestations, Gallatin District, Gallatin National Forest, 1973 Author: McGregor, Mark D., United States. Forest Service. Northern Region. State & Private Forestry Mountain pine beetle infestations have continued at epidemic level in lodgepole pine stands since 1969 in the West Gallatin River drainage. This infestation has increased at about a 1.9:1 buildup ratio annually. Since the outbreak began in 1969, surveys indicate that approximately 22,354 merchantable size trees have been killed with an estimated volume loss of 1,061 MMBF. This is a total of about 27 percent of the merchantable lodgepole pine within areas surveyed. Additional tree mortality and volume loss have occurred, but not all infested areas were surveyed due to land exchange between Big Sky Corporation, Burlington Northern Railroad, and the Forest Service. Operational control of felling and burning, and salvage logging of infested trees was initiated in 1971. This action did little to slow the impetus of the outbreak, because the complete infestation could not be suppressed. The outbreak is expected to continue at epidemic levels in 1974, with an increase in the number of infested trees. A cooperative administrative study between the Northern Region and Intermountain Forest and Range Experiment Station is planned in fiscal year 1975 to determine if silvicultural methods can be used to control mountain pine beetle in mature and overmature overstocked lodgepole pine stands on the Gallatin National Forest. Close

• 190. [Article] Impact of copper smelter emissions on two subalpine ecosystems near Anaconda, Montana : preliminary report

  Preliminary analysis of data from this study in the mountains southwest of the Anaconda Copper Smelter, an industrial source of SO2 and heavy metal particulate, reflects a complex pattern of pollutant ...

  Citation × Citation Citation Abstract Copy Title: Impact of copper smelter emissions on two subalpine ecosystems near Anaconda, Montana : preliminary report Author: United States. Forest Service. Northern Region. State & Private Forestry, Bissell, Gael, Walsh, Natalie Preliminary analysis of data from this study in the mountains southwest of the Anaconda Copper Smelter, an industrial source of SO2 and heavy metal particulate, reflects a complex pattern of pollutant impact. The differential effect of smelter emissions on plant life in the study area is best explained by the interrelationship of several factors including distance from the smelter, elevation, topography, and the position of the plant community on the landform. The data indicates that the ecological consequences of air quality degradation can be severe. Dramatic changes in plant community composition and serious reductions in vegetative cover were observed in the two forested ecosystems sampled. Tree coverage up to 66 percent was measured on control sites but dropped to less than 20 percent within 8 miles of the smelter. Shrub cover also varied directly with exposure to SO2 concentration; near the smelter coverage was only 3 to 6 percent but was 50 to 66 percent at the remote sites. Living trees near the smelter had only one half the needle retention of those on the distant sites. Up to 30 cm. of soil has eroded from the severely affected sites and normal microbial decomposition and nutrient cycling may be severely impaired. The results of this study provide the land manager with information regarding the ecological consequences of air quality degradation in forested mountainous areas. Title: Impact of copper smelter emissions on two subalpine ecosystems near Anaconda, Montana : preliminary report Author: United States. Forest Service. Northern Region. State & Private Forestry, Bissell, Gael, Walsh, Natalie Preliminary analysis of data from this study in the mountains southwest of the Anaconda Copper Smelter, an industrial source of SO2 and heavy metal particulate, reflects a complex pattern of pollutant impact. The differential effect of smelter emissions on plant life in the study area is best explained by the interrelationship of several factors including distance from the smelter, elevation, topography, and the position of the plant community on the landform. The data indicates that the ecological consequences of air quality degradation can be severe. Dramatic changes in plant community composition and serious reductions in vegetative cover were observed in the two forested ecosystems sampled. Tree coverage up to 66 percent was measured on control sites but dropped to less than 20 percent within 8 miles of the smelter. Shrub cover also varied directly with exposure to SO2 concentration; near the smelter coverage was only 3 to 6 percent but was 50 to 66 percent at the remote sites. Living trees near the smelter had only one half the needle retention of those on the distant sites. Up to 30 cm. of soil has eroded from the severely affected sites and normal microbial decomposition and nutrient cycling may be severely impaired. The results of this study provide the land manager with information regarding the ecological consequences of air quality degradation in forested mountainous areas. Close