438 Thirtieth Annual Report 



In April, 1919, specimens of a small beetle were received from 

 Mr. C. J. Wood of the Mesa Experiment Farm with the report that 

 they were destroying cotton by feeding just below the surface of 

 the soil on the seedlings as they were emerging from the ground. 

 So large a percentage of the cotton in one experimental half-acre 

 was thus destroyed as to make replanting necessary. This particu- 

 lar half-acre was being tested with cottonseed meal as a fertilizer, 

 and the assumption was that the fertilizing material was attractive 

 to the beetles. The pests were most numerous in this plot and a 

 quantity was taken for feeding tests. These tests, while not con- 

 clusive, indicated the probable correctness of the above assumption. 

 The beetles fed readily on crushed cotton seeds and particularly on 

 the lint remaining with the seeds before any seeds had germinated 

 or where no young plants were present. When young plants ap- 

 peared they seemed to attack them only in part and as a sort of 

 change or variation of diet. Irrigation of the affected area of soil 

 was effective in preventing damage to the replanting, and is there- 

 fore suggested as the proper control measure. This pest is a small 

 dark brown to black beetle, oblong, and between three-sixteenths 

 and one-fourth of an inch long. It is provisionally classified as 

 Blapstinns pimalis. 



The corn stalk borer mentioned in the Twenty-ninth Annual 

 Report has been identified as Diatraea lineola, a species not hitherto 

 recorded as an economic insect. It is, however, so closely allied to 

 the larger corn stalk borer of the East (Diatraea zeacolella) , and its 

 habits and life history appear to parallel that pest so closely, that for 

 all practical purposes it may be regarded as the same. 



During the year the department moved into new quarters m 

 the Agriculture Building, thus securing adequate space for its pres- 

 ent activities, but with only the most meager equipment. Funds 

 for this fiscal year did not permit the immediate remedying of this 

 weakness, and while in the end the change will result in great 

 benefit to our work, it placed a certain temporary handicap thereon, 

 which it is expected will be largely removed in the next fiscal year. 



