308 ANNUAL REPOETS OF DEPARTMENT OF AGRICULTURE 



which will be necessary under present conditions. Some of the 

 States involved have agreed to aid in this work, and New York 

 has in fact appropriated $25,000. 



The Dominion of Canada is heartily cooperating in this inves- 

 tigation. 



The sorghum midCxE. — Since the publication in 1911 of a prelimi- 

 nary report on investigations of the sorghum midge, it has been 

 apparent that this pest is the limiting factor in the production of 

 the tjrain sorghums in southern and western Texas and elsewhere. 

 Investigations were begun two years ago, and we have now a simple 

 and effective preventive method, based on agronomic and cultural 

 practices, which promises almost complete relief from this formi- 

 dable and wasteful pest. This will soon be given out to the growers. 



The so-called green bug. — The entomologists of Kansas, Missouri, 

 and Texas have been cooperating with the Federal field-crop insect 

 investigators in conducting a survey in order to determine the status 

 of the green bug in the region most subject to its ravages. The re- 

 sults of this survey have shown conclusively that major outbreaks 

 of this destructive wheat pest are dependent exclusively on the 

 l^resence of volunteer grain, which permits uninterrupted breeding 

 of the pest throughout the year. In northern Texas, where dry con- 

 ditions prevailed last fall and no volunteer grain was available, the 

 green bug was almost absent. In northern Oklahoma and south- 

 central Kansas, however, where conditions permitted volunteer grain 

 to flourish, there appeared destructive local outbreaks of the insect, 

 which did considerable injury, especially to oats. It is proposed to 

 make an annual survey like this and to forecast general outbreaks 

 of the green bug for some months in advance. The remedy for the 

 situation, however, obviously is for farmers to abandon the prac- 

 tice of allowing volunteer grain to spring up and become perma- 

 nent breeding places for this pest. 



Grasshoppers. — As stated in last year's report, the last session 

 of the Sixty-sixth Congress ordered an investigation of methods for 

 the control and destruction of grasshoppers, appropriating for this 

 work the sum of $40,000, which became available on July 1 last. 

 During the past year it has been found unnecessary to use more than 

 $20,000 of this money. The results of the activities under this appro- 

 priation have been the saving of crops in North Dakota and Wyo- 

 ming alone in an amount to exceed $600,000. In the former State 

 normal conditions now prevail. In addition to this, much work of 

 a similar character has been done in Oregon, California, Arizona, 

 and other States. An expert has also been stationed in northern 

 Texas who has learned much that will be useful in case of grass- 

 hopper increase. At the present Avriting outbreaks of large propor- 

 tions are in progress in Montana and Wyoming. The bureau foresaw 

 this and established a field laboratory 'at Billings, Mont., in April 

 last, and has four experts on the ground busily engaged in aiding 

 farmers and extension workers in combating the pest. The Federal, 

 State, and Canadian entomological forces have formed an informal 

 organization to aid in the work of controlling grasshoppers by 

 adopting uniform plans of procedure. 



The Hessian fly. — Thanks to the work of State and Federal 

 entomological workers, the wave of Hessian-fly infestation of 1920-21 

 has passed over the winter- wheat belt and has waned without inflict- 



