190 Bulletin 87 



The plan suggested can be modified to suit the conditions and 

 individual ideas of the alfalfa grower. For instance, instead of a 

 single land or strip across the middle of a field a square patch ex- 

 tending across two or three lands may be left in the center of the 

 field. This method is specially desirable when there is cotton on. 

 more than two sides of the alfalfa. 



Alfalfa growers who have no cotton of their own to protect will 

 frequently secure full returns in benefits to the alfalfa crop itself 

 from the adoption of the foregoing suggestions. Owners of neigh- 

 boring cotton fields should be given an opportunity to assume the 

 expense of these measures, rather than be obliged to sufifer with- 

 out recourse severe losses from insects driven in from alfalfa fields. 

 Cotton growers should keep in touch with their neighbors and ar- 

 range with the owners of adjoining alfalfa fields for cooperation in 

 the control of pests. 



Reference has been made to the matter of driving the cotton 

 square daubers out of a cotton field or of concentrating them within 

 the field. Attention has also been called to the fact that an excess 

 of the insects above the number capable of causing maximum dam- 

 age may be considered as harmless, for the time being at least. 

 The unusual activity of the adult cotton square daubers can, the 

 writer believes, be taken advantage of in driving the insects by 

 means of a device which he has designed. A second device is de- 

 signed to capture the insects after they have been concentrated on 

 a few rows. One of each of these devices has been constructed and 

 the work of perfecting them will be continued as the opportunity 

 for further field tests is presented. 



THE SOUTHWESTERN COTTON STAINER 



The Southwestern cotton stainer (Dysdercus albidivcntris Stal.) 

 has been found on cotton in various parts of the Salt River Valley 

 and at Sacaton. This insect is related to the Florida cotton stainer, 

 which is a well known cotton pest in the Sea Island cotton growing 

 district of Northern Florida. Other species occur in the West 

 Indies, Central, and South America. The adult cotton stainer is 

 from six to seven-sixteenths of an inch in length, the males being 

 considerably smaller than the females. The adults are strikingly 

 colored with a combination of black, straw yellow, orange brown, 

 and orange red. The insects breed upon the cotton plants. In 

 the immature or nymphal stages the bright orange red is the pre- 

 dominating color. The cotton stainer does its damage by feeding 



