2 ANNUAL REPORTS OF DEPARTMENT OP AGRICULTURE, 1951 
For s Contii 
dibromide simplifies fight against bark beetles 1G 
Weevil-ri ne hybrids developed 16 
Turpentine b tome vicious tree killers 16 
bhern pine beetle breaks out in South 17 
imologists assist ii ag wind-thi 17 
Survi I iropean pine shoot moth aids in selection of 
» for red pine 17 
Control campaigns against gypsy and brown-ts 18 
Control operations wipe out source of bait lure is 
Large-scale trappii binued . . . 18 
Defoliated acreage lowest in 25 years IS 
Simplified certification procedures approved by shippers 19 
II r take-off from automobile speeds fumigation 19 
Brown-tail moth at low ebb 
I forage ii 20 
Control campaign against grasshoppers contii ued 20 
Upswing in grasshopper numbers requii binued control 
programs 20 
New insecticides stimulate farmer participation 20 
Crop baiting drops off as spraying ea rol 21 
i:> cord acreage of range Lands treated 21 
Aldrin recommended for grasshopper control 21 
Severe infestations expected in 1951 
Mormon crickets controlled 
r protect inn from insects provided for stored grain 23 
cticides control sugarcane borer on large -cale 24 
Insecticides control legume insects '-'4 
les-grass scale hard hit by freeze and drough.1 
European com borer Bpreads into seven more States 25 
Distribution of DDT residues on corn determined 26 
Some wheats and barleys resistant to hessian fly 26 
■ l grains threatened by greenbugs and other pests 26 
Control for red harvester ant improved 27 
Insects affecting man 27 
Community-wide tick-control programs prove successful 27 
Search for new mosquito insecticides continued 27 
House flies develop resistance to new insecticides 
House flies survive lifetin e exposure to DDT 28 
Flight range of flies studied with aid of radioactive isotopes 
Radioactive DDT used to study sites of action of insecticide 
Clear Lake mats controlled with TDE Larvicide 29 
Cultivated Heliopsis plants yield extract more toxic to house flies than 
thai from wild plants 29 
New n aterials considered as insect repellents 30 
Snow-water n osquitoes controlled in Oregon resort areas - 30 
Treating mosquito breeding grounds in Alaska reduces following 
ison's mosquito population __ 30 
Application of insecticides to breeding area- offers promise in control 
ofsand fly 30 
Keys to identification of troublesome pests in Alaska supplied ; ^l 
Insects affecting animals. ; ">l 
New Bcrew-worm remedy developed .. 31 
Unique approach bo Bcrew-worm control Btudied 31 
Studies of biology and control of horse flies provide significant facts 
High- and low-pressure spraj applications marly equal in effectivi 
for control of cattle grubs_ 
Improvement in livestock dips Bought 82 
Measures to control imported fire ant studied - 33 
ehold insects ... 88 
bicides tested for control of ants in homes 
■ <! woolens can be protected against fabric pests for ■'* yean ; ^ ; > 
I urther developments in control of fabric pests look promising 33 
military subsist - from insect attack investigated. 8 I 
I of insect icia 8_ 
city of dieldrin to livestock determined 84 
I at i :• >r presence of insect icides 
l • ecticidal residues in milk of sprayed dairy cat tie determii 
