438 journal of economic entomology [vol. 10 



Distribution 



As previously stated, this insect has a wide distribution in Cali- 

 fornia. It has been taken in great numbers in Alameda County and 

 received from Eldorado County by the writer and has been reported 

 b}^ others from Los Angeles, Inyo (Death Valley and Argus Moun- 

 tains), Imperial and San Luis Obispo Counties in California and also 

 from the states of Colorado, Utah, Arizona and New Mexico. 



Food Plants 



The food plants are only imperfectly known and include in California, 

 the following: Alfalfa (Imperial County), tomatoes (San Luis Obispo 

 County), spruce (Los Angeles County), Pinus monophylla Torr. 

 (Argus Mountains, Inyo County) as reported by Crawford, and on 

 the following plants on the campus of the University of California, 

 Berkeley Alameda County, by the writer: tobacco, petunia, Solarium 

 marginatum Linn., S. verhascifolium Banks, Datura sanguinea R. &. P., 

 and lochroma tuhulosa Benth. It was also received from Placerville, 

 Eldorado County, where it was abundant on potatoes. In Colorado 

 it was first taken on cultivated pepper and later on tomato and com- 

 mon nightshade {Solarium nigrum Linn.). In Arizona Crawford lists 

 it on arborvitae and Pursia sp. 



Control 



Though unprotected and comparatively delicate, this insect is not 

 at all easy to control. At least two factors enter into this: its fondness 

 for the undersides of the older leaves near the ground where it is well 

 protected from sprays, and the delicate nature of the food plants 

 which will not permit the use of a strong spray of any kind. The first 

 factor can only be overcome by very great care in applying the remedy 

 and the second by the use of tested materials. The oil and soap sprays 

 are specially to be avoided as they seem to be particularly destructive 

 to solanaceous plants and are not recommended unless used in very 

 diluted proportions and then only after experimenting on a few plants. 

 Nicotine sulphate or black leaf forty may be used with comparative 

 safety at the rate of from 1 to 1,000 to 1 to 1,500. Prof. C. P. Gillette 

 writes that in Colorado, several remedies have'been studied, especially 

 on tomatoes, and only lime-sulphur proved successful. The com- 

 mercial product was used in the proportions of 1 to 40 and killed the 

 psyllids without serious injury to the plants. A spray of about the 

 same strength has been used experimentally in spraying potatoes for 

 fungous diseases, but proved to be positively harmful to the crop.^ 



1 Stewart, F. C. and French, G, X, BuL No. 347, N. Y. Agrcl. Exp. Sta., pp. 79, 

 81, March, 1912. 



