REPORT OF THE ENTOMOLOGIST. 



United States Department of Agriculture, 



Bureau of Entomology, 

 Washington, D. G., August 28, 1923. 

 Sir: I submit herewith a report of the work of the Bureau of 

 Entomology for the fiscal year ended June 30, 1923. 



L. O. Howard, 

 Entomologist and Chief of Bureau. 

 Hon. Henry C Wallace, 

 Secretary of Agri-culture. 



DECIDUOUS FRUIT INSECT INVESTIGATIONS. 



Investigations of deciduous fruit insects have been carried out 

 under the direction of Dr. A. L. Quaintance, as formerly. 



The Japanese beetle. — Work against the Japanese beetle in co- 

 operation with the Federal Horticultural Board and the New Jer- 

 sey and Pennsylvania State Departments of Agriculture has been 

 vigorously prosecuted. It is subdivided into the following sections : 

 Administration, quarantine enforcement, biologic investigations, 

 beetle insecticide investigations, grub insecticide investigations, and 

 field work. The regulations established in Federal Quarantine 48, 

 as well as the restrictions of the quarantine laws of Pennsylvania 

 and New Jersey, have been enforced during the year. Something 

 over 483,000 baskets of corn were inspected during the summer and 

 fall of 1922, and many thousands of beetles were removed from the 

 corn before shipping certificates were given. A large amount of 

 inspection of nursery, ornamental, and greenhouse products has 

 been done and certificates issued when the owner was entitled to 

 them. Scouting to determine limits of infestation has been carried 

 out as heretofore and reveals a constant natural spread of the beetle 

 which can not be prevented. Thus at the beginning of the season 

 of 1922 the infested area covered some 270 square miles, while at 

 the close of that season it had spread to over 770 square miles, repre- 

 senting a spread of about 200 per cent. 



Much additional information has been accumulated on the biology 

 of the insect and also on its behavior under varying environmental 

 conditions. The relationship existing between common farm prac- 

 tices in the community and grub infestation has also been carefully 

 studied, and it appears that present farm practices are favorable to 

 the insect. Certain modifications appear desirable from the stand- 

 point of control of the beetle, such as extremely late fall plowing and 

 late spring plowing, which tend to reduce the number of grubs. 



One of the principal activities under this heading has to do with 

 the importation of foreign parasites. Several shipments of beneficial 



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