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Bah. ee 
feeding of those remaining was greatly reduced. Previous experiments 
had shown that the action was repellent, inasmuch as the larvae fed nor-— 
mally when placed on untreated foliage." 
New method of counting beet leafhoppers.--W. C. Cook, Modesto, 
Calif., reports that "A new apparatus to be used in measuring populations 
of Eutettix tenellus Bak. on varieties of sugar beets was built and tested. 
This was essentially a manure fork, with tines 13 inches long and 1 inch 
wide, placed 1 inch apart. The last inch of tine is tapered to a point 
and turned slightly upward. The fork is covered with fly spray and shoved 
under the plants to be sampled, Then the plants above and surrounding the 
fork are sprayed and the insects falling on the first 12 inches of tine 
are counted. The counting area was one half square foot. * * * It is be- 
lieved that, although this method is time-consuming, it gives a very accu- 
rate count." 
Derris dust effective against tobacco flea beetle.--F. S. Chamber- 
lin, Quincy, Fla., who has been testing the comparative toxicity of three 
fluorine compounds and derris against Epitrix parvula Fab. under labora- 
tOry conditions, reports that "The outstanding feature of the results is 
the perfect kill obtained with the diluted derris dust, a mixture of der- 
ris (0.4 percent rotenone) and tobacco dust (1 to 10). The poison acted 
either through contact or the 'clean-up method' as no feeding on foliage 
occurred. The kill resulting from derris took place in the first 24 
hours, whereas the fluorine compounds continued to kill over a 48-hour 
period." 
Safety in arsenical treatments for cabbage insects.--In a summary 
of the season's studies of arsenical residue on cabbage, W. J. Reid, Jr., 
Charleston, S. C., says, "from the results of the first season's studies, 
so far as the arsenic residue is concerned, arsenical applications as 
used in the tests (4 pounds of lead arsenate per acre per application) 
may be safely made on cabbage until 20 days before harvest, provided the 
marketed heads have been stripped down to contain not more than four 
loose outer leaves. Stripping to these four loose outer, or wrapper, 
leaves is the usual commercial practice in the Charleston, S. C., area." 
FOREST INSECTS 
Egg parasite aids in controlling pine tip moth.--L. G. Baumhofer, 
Coeur d'Alene, Idaho, reports as follows on the importance of Trichogramma 
minutum Riley: "This egg parasite destroyed 33 percent of the eggs 
of Rhyacionia neomexicana Dyar, attacking the host eggs from the last 
of April and throughout May. The percentage of parasitization is based on 
420 eggs collected in the field during the egg-laying period. Adult par- 
asites emerged from May 24 to June 5." 
Saving the parasites in Coeur d'Alene forest.—-Reporting on natu- 
ral control of the mountain pine beetle (Dendroctonus monticolae Hopk.), 
