13 ~ 
A regional survey party under Dr. K. A. Salman completed its 1931 
program on the Modoc National Forest July 16. The work in this area was 
started May 15. During this period six permanent sample plots, covering 
1,920 acres, were mapped, tagged, and marked, four sample sections were 
cruised, and about 70 miles of strip counts were run, covering approx-— 
imately 4,000 acres. The tendencies of the western pine beetle infesta— 
tion for the season of 1931 were becoming evident by the 15th of July. 
Attacks by the summer generation indicate that there will be about four 
times as many trees killed by this attack as were killed by the summer 
generation of 1950. On the poor sites the infestation is becoming con- 
Spicuous and can be classed as epidemic. The survey party moved to the 
Sierra National Forest, and will be engaged on the examination of yellow 
pine areas in the San Joaquin watershed until August 15. 
Albert Wagner and G. R. Struble started work at the Stanislaus 
branch of the California Forest Experiment Station June 9. A small field 
laboratory, equipped with a series of large screen cages, was set up at 
t he Stanislaus base in connection with Mr. Struble's study of the fir 
engraver beetle. 
Nutritional studies of the western pine beetle were carried on at 
the Berkeley, Calif., field laboratory by R. N. Jeffrey’ The initial ob— 
jective of these experiments is to determine whether the western pine 
beetle larvae will develop successfully in yellow pine phloem without 
the aid of microorganisms such as yeasts, which break down the sugars of 
the inner bark. A trip was made to the Stanislaus Forest with J. M. 
Miller to collect brood material and fresh yellow pine samples for this 
study. 
A trip was made to the Sequoia and General Grant National Parks 
by J. M. Miller during the period from July 5 to 10. An examination 
was made of the control work carried on in Grant Park during May and 
June, 1931, where a number of large infested sugar pine trees in the 
camp ground areas were treated to destroy the mountain pine beetle. 
J. C. Evenden, of the Coeur d'Alene, Idaho, field laboratory, 
spent the period from June 3 to June 19 visiting Ogden, Utah; the Tar- 
ghee National Forest; Cody, Wyo.; Yellowstone Park; and Missoula, Mont. 
The purpose of his trip was to meet Dr. F. C. Craighead and J. M. Miller 
for conference and to inspect control work on the Targhee National Forest 
and the experimental spraying project in the Cody Canyon. 
Mr. Evenden spent the week of July 12 to 18 at Sullivan Lake, 
Kaniksu National Forest, with W. D. Bedard, who with field assistants 
is making an intensive study of the mountain pine beetle and Douglas 
fir beetle. Mr. Bedard is securing much interesting and valuable in- 
formation relative to sex ratio of emerging adults, emerging of parent 
adults and subsequent reattack of other trees, brood potentials, season-— 
al histories, etc., which will all contribute toward a better understand— 
ing of these two important forest insects and serve as a foundation up-— 
on which to base more efficient methods of control. 
