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• 21. [Article] Distribution of larch casebearer parasites in the crowns of western larch trees in the northern region

  A study was made to determine the distribution of parasites of the larch casebearer, Coleophora laricelia, within crowns of western larch, Larix occidentalis. The most common parasites recovered in order ...

  Citation × Citation Citation Abstract Copy Title: Distribution of larch casebearer parasites in the crowns of western larch trees in the northern region Author: United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E., Tunnock, Scott, McGregor, Mark D. A study was made to determine the distribution of parasites of the larch casebearer, Coleophora laricelia, within crowns of western larch, Larix occidentalis. The most common parasites recovered in order of their abundance, were: Agathis pumila (Ratz.), Diciadocerus sp. near westwoodii, Spilochalcis albifrons (Walsh), and MesopoZobus sp. Parasitism by A. pumila was significantly higher in the outer limbs of the upper one-third of the crown. Diciadocerus sp. near westwoodii was highest on the inner branch portions regardless of crown level. S. albifrons parasitized more casebearers on the lower-outer portion of the crown. Parasitism by Mesopolobus sp. was uniform throughout the crown. Title: Distribution of larch casebearer parasites in the crowns of western larch trees in the northern region Author: United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E., Tunnock, Scott, McGregor, Mark D. A study was made to determine the distribution of parasites of the larch casebearer, Coleophora laricelia, within crowns of western larch, Larix occidentalis. The most common parasites recovered in order of their abundance, were: Agathis pumila (Ratz.), Diciadocerus sp. near westwoodii, Spilochalcis albifrons (Walsh), and MesopoZobus sp. Parasitism by A. pumila was significantly higher in the outer limbs of the upper one-third of the crown. Diciadocerus sp. near westwoodii was highest on the inner branch portions regardless of crown level. S. albifrons parasitized more casebearers on the lower-outer portion of the crown. Parasitism by Mesopolobus sp. was uniform throughout the crown. Close

• 22. [Article] The relationship of an insect infestation on lodgepole pine to fluorides emitted from a nearby aluminum plant in Montana

  Stepwise multiple regression techniques were used to statistically analyze the relationships between damage caused by the pine needle sheath miner Zell-aria haimbachi (Busck); a needle miner, Oenerostoma etrobivorum ...

  Citation × Citation Citation Abstract Copy Title: The relationship of an insect infestation on lodgepole pine to fluorides emitted from a nearby aluminum plant in Montana Author: Carlson, Clinton E., United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E., McGregor, Mark D. Stepwise multiple regression techniques were used to statistically analyze the relationships between damage caused by the pine needle sheath miner Zell-aria haimbachi (Busck); a needle miner, Oenerostoma etrobivorum (Zeller); sugar pine tortrix, Choriatoneura Zambertiana (Busck); and ambient and foliar concentrations of fluoride in lodgepole pine (Pinue contorta v. Zatifolia Engelm.) near the Anaconda Aluminum Company at Columbia Falls, Montana. Foliar fluoride concentration was significantly related (0.01 level) to needle miner damage and to damage caused by the pine needle sheath miner. The data strongly indicate that fluoride is a contributing factor in predisposing pines to damage by these insects. Title: The relationship of an insect infestation on lodgepole pine to fluorides emitted from a nearby aluminum plant in Montana Author: Carlson, Clinton E., United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E., McGregor, Mark D. Stepwise multiple regression techniques were used to statistically analyze the relationships between damage caused by the pine needle sheath miner Zell-aria haimbachi (Busck); a needle miner, Oenerostoma etrobivorum (Zeller); sugar pine tortrix, Choriatoneura Zambertiana (Busck); and ambient and foliar concentrations of fluoride in lodgepole pine (Pinue contorta v. Zatifolia Engelm.) near the Anaconda Aluminum Company at Columbia Falls, Montana. Foliar fluoride concentration was significantly related (0.01 level) to needle miner damage and to damage caused by the pine needle sheath miner. The data strongly indicate that fluoride is a contributing factor in predisposing pines to damage by these insects. Close

• 23. [Article] Observations on the impact of western spruce budworm on the Valley Creek Drainage, Flathead Indian Reservation, Montana

  The western spruce budworm, Choristoneura occidentalis (Free.), has caused a measurable impact on a portion of the Flathead Indian Reservation during a 5-year infestation period. This survey showed that most ...

  Citation × Citation Citation Abstract Copy Title: Observations on the impact of western spruce budworm on the Valley Creek Drainage, Flathead Indian Reservation, Montana Author: United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E. The western spruce budworm, Choristoneura occidentalis (Free.), has caused a measurable impact on a portion of the Flathead Indian Reservation during a 5-year infestation period. This survey showed that most of the grand fir and alpine fir, and 13.8 percent of the Douglas fir has been top killed in the Valley Creek area west of Arlee, Montana. The survey also disclosed that a total net growth loss of 19.6± 1.9 board feet per acre per year has occurred since 1967. Significant growth reduction at the 99 percent level occurred in Douglas-fir, grand fir, alpine fir, and western larch. Little mortality in trees 5 inches d.b.h. and greater has occurred to date. Of the trees under 5 inches d.b.h. 55.6 percent were not suitable for Christmas tree production because of insect damage. Title: Observations on the impact of western spruce budworm on the Valley Creek Drainage, Flathead Indian Reservation, Montana Author: United States. Forest Service. Northern Region. State & Private Forestry, Bousfield, Wayne E. The western spruce budworm, Choristoneura occidentalis (Free.), has caused a measurable impact on a portion of the Flathead Indian Reservation during a 5-year infestation period. This survey showed that most of the grand fir and alpine fir, and 13.8 percent of the Douglas fir has been top killed in the Valley Creek area west of Arlee, Montana. The survey also disclosed that a total net growth loss of 19.6± 1.9 board feet per acre per year has occurred since 1967. Significant growth reduction at the 99 percent level occurred in Douglas-fir, grand fir, alpine fir, and western larch. Little mortality in trees 5 inches d.b.h. and greater has occurred to date. Of the trees under 5 inches d.b.h. 55.6 percent were not suitable for Christmas tree production because of insect damage. Close