Mountain pine beetle, Dendroctonus ponderosas Hopk., reached near epidemic levels in lodgepole pine stands in the Sulphur Creek-Black Butte area. Lodgepole pine are probably more susceptible due to the overstocked conditions of stands, and high incidence of girdling of the base of trees by porcupines. The infestation in this area...
Epidemic levels of the pine butterfly, Neophasia menapia (Felder and
Felder) have been evident in ponderosa pine stands in the Bitter Root
Valley since 1969. Evaluations of this infestation were initiated in
1970 to assess overwintering egg populations at 20 locations within
the infestation (Ciesla et al. 1971). Defoliation was...
The bark beetle infestation in ponderosa pines defoliated by pine looper, Phaeoura mexicanaria (Grote) on Cook Mountain was resurveyed in 1971. Most of the surviving defoliated trees have "greened up" appreciably. Bark beetle activity was greatly reduced. The red turpentine beetle, Dendroctonus vaZens LeConte, was the only bark beetle observed...
The variable oak leaf caterpillar, Heterocampa manteo (Dbldy.), has defoliated hardwoods in two North Dakota locations for 3 years (Fig. 1). This is the second consecutive year its damage has been monitored. Monitoring has been done cooperatively with William Brandvik, Associate
State Entomologist, North Dakota Department of Agriculture.
The western hemlock looper, Lambdina fiscellaria Zugubrosa Hulst, caused, aerially visible defoliation on approximately 10,000 acres of State, private, and Federal forests of northern Idaho in 1972. This is the first report of noticeable defoliation by this insect in Region 1 since the late 1930's (Dewey et al. 1972).
Mountain pine beetle activity has increased from about 350 infested trees in 1972 to over 1,200 infested trees in 1974 on the Bitterroot National Forest. The majority of infestation occurs in second-growth, overstocked, ponderosa pine stands in the West Fork Bitterroot drainage. An increase in number of trees killed is...