
-— 7 - 
xanthomelaenae and others to attack by Tetrastichus sp. and reports that 
adult parasites are emerging from both lots. He also exposed eggs that 
had been exposed to attack by one parasite to attack by the other and in 
all cases observed that only adults of the Species to which the eggs were 
first exposed developed. No true secondary parasitism was observed, al- 
though there is competition, as only one parasite has been found in a 
beetle ege. Mr. Berry adds, however, that 'there is a possibility that 
more than one may develop in the same egg.'" 
White-grvb problem.--R. A. St. George, Asheville, N. C., says that 
"During the month of July reports and specimens were received from J. S. 
Holmes, State forester of North Carolina, to indicate that many of the 
white-grub larvae at the State Nursery, located near Clayton, have been 
heavily parasitized. The parasitic larvae superficially resembled those 
of a robber fly. They have been submitted for determination. Several 
entire seed beds have already been lost this year and Mr. Holmes expressed 
the hope that the mortality would be high and that the grubs would be 
controlled by this enemy. No damage has been reported to the arsenic-— 
treated beds established this spring. 
Control of mountain pine beetle in Crater Lake National Park.—- 
F. P. Keen, Portland, Oreg., reports that "The season's program of moun- 
tain pine beetle control in the pine stands of Crater Lake National Park 
was completed on July 25, and the two camps employing about 50 men were 
disbanded. For the first time since this project was started in 1925 
the entire infested area of the southern half of the park and adjacent 
National Forest lands was completely covered with the control operations, 
all infestation found was treated, and the cost of the work was kept with- 
in the original estimate and allotment. More than 20,000 trees were 
treated," 
Western pine beetle yields slowly to oil sprays.—-K. A. Salman and 
P. C€. Johnson, Berkeley, Calif., report that "An additional series of 
about 20 trees infested by summer broods of the western pine beetle were 
felled during the period July 19 to 29 and treated with oil sprays pro— 
vided by the Standard 0il Research Laboratory. Results as found in pre- 
ceding experiments indicate that the toxic effect of these oils is very 
slow in its operation and that insects in the larval stages do not die 
for some time after application of the oils. Owing to the rather prom— 
ising developments shown by the trees that were treated last spring, con-— 
Siderable time has been devoted to this experiment in the hope that a 
method can be developed that will make it possible to treat trees dur~ 
ing the summer season, when burning is impracticable, or during the early 
stages of brood development while the bark is still tight and peeling is 
a very expensive operation. One experiment carried out by Chemist Gay 
of the Standard 0il Laboratory during the latter part of June consisted 
of spraying with oil a standing lodgepole tree infested by the mountain 
pine beetle. This tree was examined by Mr. Salman on July 15, when none 
of the insects could be found alive, all apparently having succumbed to 
the action of the oil. Owing to the promising results secured, further 
experimentation with lodgepole is planned during August." 
