BUREAU OF ENTOMOLOGY AXD PLAXT QUARANTINE 47 
The threat of the golden nematode to the potato industry now re- 
quires extensive annual soil examinations to determine the location 
and possible spread of this pest. A machine for washing soil samples 
to recover nematode cysts has been developed, which is expected to 
reduce by 70 percent the labor now required for manual processing. 
Machines were also developed or modified for spraying insecticides 
from aircraft, for spreading dry grasshopper bait from trucks, and for 
controlling leafhoppers with truck-borne mist blowers. 
The engineers in the Bureau of Plant Industry, Soils, and Agricul- 
tural Engineering have cooperated in these undertakings. 
IMPORTED BEETLES CONTROL KLAMATH WEED 
ON WEST COAST 
Early colonies of beetles imported from Australia have nearly elim- 
inated the Klamath weed at many points of release in California, and 
the cleared areas are rapidly increasing in size. This weed crowds 
out grass on range, and animals forced to eat it for lack of better forage 
become sickly and underweight. Several years ago two species of 
Chrysolina beetles were found by Australian scientists to feed exclu- 
sively on this weed, known there as St. Johnswort, and were imported 
to that country from Europe to keep it under control. The Bureau in 
cooperation with the University of California undertook to adapt the 
beetles to conditions on this continent, and colonies were released in 
patches of the weed. During 1947^8 they had multiplied so that it 
was possible to release more than half a million beetles in California. 
Large numbers were also released in Oregon, Washington, Idaho, and 
Montana, in cooperation with the State agricultural experiment sta- 
tions. A program for colonizing the beetles in the national forests of 
these States, in cooperation with the Forest Service, is now under way. 
HONEY BEES AND OTHER POLLINATING INSECTS 
Lack of Pollination a Serious Threat to Seed Production 
Seed production in this country is threatened with a serious lack of 
insect pollinators. Wild pollinating insects have virtually disap- 
peared in many localities following the use of the new insecticides or 
other modern agricultural practices that destroy their nesting places. 
Honey bees could easily be substituted for wild bees, but an alarming 
number of beekeepers are giving up their colonies because the price 
they receive for their honey is below the cost of production. They 
have little incentive to provide bees for the benefit of legume-seed 
producers and other farmers in the pollination of crops. There is 
already an acute shortage of legume seeds, particularly of the im- 
proved varieties. Unless the producers of these crops realize their 
dependence on bees and make arrangements to recompense beekeepers 
for the services of their colonies, the shortage can be expected to 
continue. 
