A survey to determine distribution and intensity of cankers and associated damage in North Dakota windbreak plantings of Russian-olive and Siberian elm was conducted in 1972. Four hundred and thirty-five (76 percent) of 574 Russian-olive examined had cankers, and 552 (72 percent) of 769 Siberian elm examined had cankers. Cankers...
The mountain pine beetle, Dendroetonus ponderosae Hopk., has been at epidemic levels in second-growth ponderosa pine stands in the Ninemile area of the Lolo National Forest and surrounding private lands since 1969. An impact survey, using two levels of photography and a small ground sample, was conducted to estimate a...
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.
Diseased conifer nursery stock, including Douglas-fir, western larch, and Engelmann spruce, was selected from the U.S. Forest Service nursery at Coeur d'Alene, Idaho, to determine (1) the most probable cause of disease, (2) the fate of outplanted diseased stock, and (3) the height growth of outplanted diseased seedlings. Fusarium spp....
The pine butterfly, Neophasia menapia (Felder and Felder), infestation on the Nezperce National Forest was aerially surveyed in mid-August 1972.
A followup ground evaluation was made in September. Results of the survey
show the infestation has increased substantially in intensity and size.
The infestation was first reported in 1971 when...
Over 10,000 acres of aerially visible western hemlock looper defoliation on grand fir was detected on State and Federal forests of central Idaho in 1972. This is the first report of this insect building up
in Region 1 since a widespread outbreak in 1937-39.
The western hemlock looper has the...
The Douglas-fir beetle, Dendroctonus pseudotsugae Hopk., has caused extensive tree mortality for the third consecutive year in the North Fork Clearwater River drainage in northern Idaho. In 1972, the infestation encompassed about 494,080 acres of commercial forest lands in this drainage. It was estimated from a tw-stage aerial photo-ground survey...