457 



Pabker (J. R.). An Outbreak of the Alfalfa Looper {Autographa 

 gamma californica, Speyer).- — Jl. Econ. Entom., Concord, vii, no. 2, 

 April 1915, pp. 286-290. 



An outbreak of the alfalfa looper {Phytometra ca'ifornica) occurred 

 in Montana during 1914, and was particularly injurious in the central 

 and south central parts. Injury by this insect was also reported from 

 South Dakota, Wyoming, Colorado, British Columbia, etc. The moth 

 was first noticed in Montana in the first week in May, being abundant 

 on currant blossoms. In June, lucerne and sweet clover were found 

 to be heavily infested with the larvae. From the middle of June to 

 the beginning of July the larvae gradually decreased in numbers. 

 From pupae collected on 10th June, moths emerged 15 days later. 

 A second brood of larvae was expected in late July or early August, 

 but so abundant were insect parasites and bacterial diseases that no 

 more larvae were observed during the remainder of the season. 

 Melilotus alba was the favourite plant of the larvae ; lucerne ranked 

 second. Larvae were also seen feeding on Lactuca pulchella, flax, 

 sugar-beet, carrots, onions, Helianthus, etc. Grains and grasses were 

 never attacked, even when adjoining heavily infested lucerne fields ; 

 gooseberries, raspberries and currants were injured only when the 

 larvae were very abundant and other food was scarce. Experimental 

 control work could be carried out only in a limited way on account 

 of the sudden appearance of the larvae. Paris green at the rate of 

 1| lb. in 50 gals, water and lead arsenate at the rate of 4 lb. (paste) 

 in 50 gals, were effective in killing the loopers. A dry ditch proved 

 in some cases an efficient barrier. The best method of preventing 

 migration was to keep a stream of water flowing through the main 

 irrigating ditches. Birds destroyed large numbers of larvae. Insect 

 parasites and disease killed so many that the second brood of larvae 

 was unable to do any damage ; two species of Apanteles and a bacterial 

 disease were the most effective o hese n lural enemies. 



QuAYLE (H. J.). The Citricola Scale {Coccus citricola, Camp.). — 

 Jl. Econ. Entom., Concord, vii, no. 2, April 1915, pp. 291-292. 



Coccus citricola is now known to occur in widely separated localities 

 in California and primarily attacks citrus trees. It has also been found 

 on pomegranate, nightshade, elm and English walnut where these 

 occur near infested citrus. The fact that the scale is susceptible to 

 fumigation for so short a period, makes it an important economic 

 factor in the citrus industry of California. C. citricola deposits eggs 

 which hatch in a day or two ; there is but one or a partial second 

 generation annually. In 1914, the young of this species began to 

 appear about the 20th April and continued until August. They settle 

 on the under side of the leaves. In November they migrate to the 

 twigs, where they remain until next spring. The following Chalcid 

 parasit ^s have been reared from this scale : — Coccophagus lunulatus. 

 How., C. lecanii. Smith, C. Jlavoscutelliwi, Ashm., and Aphycus sp. 

 The scale becomes very resistant to fumigation during September, 

 although no external change can be noted. Fumigation between July 

 and the beginning of September has proved satisfactory. 



