BUEEAU OF ENTOMOLOGY. 533 



2. The destruction by burning of all adjacent undergrowth in the 

 late fall or winter, and the removal of all wild food plants and 

 debris in which the insects could find winter quarters. 



3. High cultivation to secure a maximum number of buds. 



4. Immediate and close cultivation of the beds after picking, to 

 destroy infested buds. 



The strawberry leaf-roller and a root-worm were also studied in 

 this locality. 



INVESTIGATIONS IN COLORADO. 



At the beginning of the fiscal year work on truck-crop insects in 

 Colorado was begun, with headquarters at Rocky Ford. The inves- 

 tigation was taken up in cooperation w4th the Rocky Ford Chamber 

 of Commerce and the commissioners of Otero County and the Rocky 

 Ford Melon Growers' Association. Work was continued until De- 

 cember 1, 1909, and resumed March 11, and continued to the end of 

 the fiscal year 1910. A preliminary test was made of the trap-crop 

 ladybird method of controlling the melon aphis, early growing 

 crucifers being used as a trap crop. The species was largely con- 

 trolled by natural enemies, so that slight damage was done. 



The yellow bear caterpillar did much damage to sugar beets and to 

 the truck crops of the upper Arkansas Valley. It was decided that 

 the best method of controlling the pest was the cleaning up and 

 burning of the rubbish in fence corners and similar places where the 

 insect hibernates. In the same way the best remedy for the larger 

 beet leaf-beetle, or " alkali bug," was found to consist in destroying 

 heaps of weeds, tufts of grass, and other debris in which the insect 

 passes the winter. 



The red spider in its occurrence on celery, beans, and other plants, 

 including shrubs, ornamental bushes, and trees, was readily con- 

 trolled by the use of a lye-sulphur solution. 



Further studies were made of other crop insects in this region. 



TRUCK INSECTS IN MISSISSIPPI. 



In the summer and fall of 1909 work was begun in the State of 

 Mississippi against truck insects, with headquarters at Starkville. 

 This work is still going on against the pests especially injurious to 

 cabbage, Lima beans, melons, tomatoes, and strawberries. 



IN CALIFORNIA. 



An especial investigation of insects damaging sugar beets and 

 truck crops has been carried on in this State with headquarters at 

 Compton, and the life histories of the insects concerned have been 

 studied and experimental work instituted. 



IN SOUTHERN TEXAS. 



The work at Brownsville, mentioned in previous reports, has been 

 continued. The onion thrips, with the melon aphis, appears to be 

 the most serious truck-crop pest of southern Texas, and as to the 

 onion thrips the work so far done indicates that unless remedial 

 measures, such as the changing of the farming methods or the appli- 



