
a7 
Mass. Mr. Parker and I collected five females and I was able to make 
a few observations on it. It isa species of Microbracon, which readily 
attacks H. laricella. The host larva is paralyzed and an egg laid ex-— 
ternally. The egg hatches in about 30 hours and the issuing larva feeds 
very rapidly, completing development in about 5 days. It then pushes 
the host larval remains out of the case and Spins a light cocoon. Pupa- 
tion takes place about eight days after the eee «her Lares Ut 
Se 
National Park, report that "Experiments were carried out with a modi-— 
fication of the oil-burning method used on Standing trees in the Rocky 
Mountain region. In this instance trees were felled, limbed, and then 
sprayed with an oil of low specific gravity, using one of the "flame-— 
thrower" back pumps. Then the logs were set on fire and the flames car— 
ried along the trunk by squirting on a small quantity of additional oil. 
Only about one-half gallon of oil was required to completely scorch an 
average-sized tree and the whole process of burning and rolling took only 
about 5 minutes. A very satisfactory kill of the brood under the thin 
bark was secured. Since this oil can be purchased for about 6 cents per 
gallon, it is estimated that the additional cost of this method of treat— 
ing over the sun-curing method will not exceed 15 cents per tree." 
Caterpillar tractor lowers cost of pine beetle control.—~"For a 
decade," reports A. J. Jaenicke, Forest Examiner for Region Six, "the 
average cost of cutting, peeling, and burning ponderosa pine trees in-~ 
fested with the western pine beetle has been about $4 per thousand 
board feet on the control projects in Oregon. * * * Jn November, 1931, 
the Fremont National Forest pioneered an experiment * * * on one of its 
control projects in ponderosa pine. Instead of peeling and burning the 
infested trees individually the infested portions of the tree trunks 
were decked into piles by caterpillar 60 and then burned. * * * With 
the experience of the Fremont experiment as a basis, the Deschutes Na- 
tional Forest in March, 1932, carried out a ponderosa pine control pro- 
Pecte wlth. the aid of a ‘caterpillar’ 60" “anda ‘caterpillar 20' ata 
cost which establishes a new record for western pine beetle control costs 
in Oregon. By the regular "cut, peel, and burn" method, the cost would 
probably have been $3.60 per thousand board feet. The Deschutes did the 
job for less than $2 per thousand board feet by good management and 
skillful handling of the caterpillars. * * * Where the caterpillar (trac-— 
tor) method can be used at a saving, it has the following advantages: (1) 
It enables control work to start before the final close of the fire sea- 
son in the fall. Piles can be prepared in advance and burning delayed 
till arrival of safe burning conditions; (2) it reduces the amount of in- 
flammable material on the ground. The log piles burn up completely. 
The scattered trees are merely charred slightly; (3) it lowers the dan—- 
ger of the spread of fires by greatly reducing their number and concen- 
trating them where they do not scorch trees or reproduction; (4) it is 
more effective in the destruction of the beetles, as 100 per cent of the 
bark is destroyed, allowing no possible chance for beetles to escape." 
