34 ANNUAL REPORTS OF DEPARTMENT OF AGRICULTURE, 1052 
losses in 1951 were estimated to amount to 1,400,000 bushels for Mon- 
tana arid 3,500,000 bushels for North Dakota. Total sawfly losses 
for both States were estimated at $10 million, based on the average 
prevailing wheal prices at harvesttime. 
I >ieldrin, aldrin, heptachlor, parathion and allethrin were tested as 
mics to destroy the feeding larvae in the wheat stems. In addi- 
tion experimental soil applications of Systox, octamethyl pyrophos- 
phoramide, heptachlor, dieldrin, and aldrin were made at three dif- 
ferent times during the growing season. None of tin--*' materials gave 
effective control although Systox destroyed 38 percent of the larvae 
in the stems when applied after the peak of adult e aergence. Chemi- 
cal treatment of seed wheat prior to planting was not encouraging. 
The most satisfactory cultural method for controlling the wheat 
stem sa wfly consist - of a -hallow cultival ion with a one-way disc plow- 
in the fall, followed by deep plowing with a moldboard plow in the 
spring. This treatment reduced tile number of adult- emerging from 
the overwintering larvae by 63 percent. 
In the wintei>wheat plot- at Choteau, Mont.. 2, 557 foreign and 
domestic winter wheat varieties were screened to determine their re- 
sistance to the sawfly. All were found susceptible and discarded. 
Solid-stem wheats are being emphasized in the winter wheat plant Lags, 
as they appear to be the only immediate source of sawfly resistance. 
The resistance work' was done in cooperation with plant breeders in 
the Bureau of Plant Industry, Soil-, and Agricultural Engineering. 
The wheat stem sawfly investigations were conducted in coopera- 
tion with the .Montana and North Dakota Agricultural Experiment 
Stations. 
Promising Research on Sugarcane Insects 
Sugarcane Itorer infestation light in Louisiana and Florida 
In the sugarcane section of Louisiana, the winter of 1950-51 was 
the coldest since ls < .' , .>. This resulted in the lightest spring borer 
infestation on record and one of the lightest at harvesttime. A L951 
survey of sugarcane at harvesttime in Louisiana showed an average 
of L8 percent of the cane joints bored as compared with 17.2 percent 
for the same areas in 1950. Numbers of aphids and other sugarcane 
insects were also the lowest on record. According to a similar survey 
in Florida, from 2.8 to s . 1 percent of the joints were bored, a lower 
figure than in 1950. 
Sugarcane tested for borer resistance 
Seven commercial and two unreleased varieties of sugarcane were 
examined for sugarcane borer infestation at Houma, La. Three of 
these carried more resistance than the resistant variety C. P. 34 120. 
In Florida the replacement of susceptible with resistant varieties has 
been of great value in decreasing borer injury. The resistant varie- 
ties in that State also produced the highest yield- of sugarcane per 
acre. This work was conducted in cooperation with the Bureau of 
Plant Industry, Soils, and Agricultural Engineering and the Florida 
and Louisiana Agricultural Experiment Station-. 
Controls SOUght for rat ions sugarcane insects 
Soil samples taken from small plot experiments in Louisiana 
showed ••! percent fewer injurious soil insects in plots treated with 
