766 EXPERIMENT STATION RECORD. 



the potatoes remained uninfested; the removal and destruction of infested potato 

 tops is therefore considered an effective and practical means of controlling this insect. 

 It was shown by experiments that moths may winter over in infested potatoes which 

 are left in the ground. Experiments with potatoes in storage showed that the insect 

 may rapidly increase under such conditions, and that a slight infestation may cause 

 the almost total destruction of large quantities of stored potatoes, if no means are 

 taken to destroy the insect during a whole winter. Experiments with carbon bisul- 

 phid in the destruction Of this species in stored potatoes were successful. It is rec- 

 ommended that 5 treatments be given to each lot of potatoes, one when the pota- 

 toes are stored, and a second, third, fourth, and fifth treatment at intervals of about 

 2 weeks. For treating 1,000 cu. ft. of space, which would hold from 200 to 250 sacks 

 of potatoes, 5 times, from 5 to 7^ lbs. of carbon bisulphid will be required. It 

 was recommended that native food plants of this species, such as Solanum douglasii, 

 S. nigrum, S. umbelliferum, and S. xanti, be destroyed. In addition to the other rem- 

 edies already mentioned, it is recommended that all potato tops in fields which had 

 been infested should be destroyed. 



Brief notes are also given on 2 species of fiea-beetles {Epitrix subcii)uta and E. 

 hirtipeimis) , for which spraying with Paris green in the proportion of 1 lb. to 150 

 gal. of water is recommended. Yellow ground crickets belonging to the genus Ste- 

 nopelmatus are sometimes reported as injuring potatoes by biting out portions of the 

 surface of the tuber. 



Successful sprayer for the pea louse, E. D. Sanderson {Rural New Yorker, 60 

 {1901), No. 2685, pp. 41, 42, figs. 2). — Notes are given on previous insecticide work 

 in controlling this insect. A description is given of the spraying machine which hag 

 been devised for operation upon infested peas. The general appearance of the 

 sprayer from a distance is that of a grain drill, and it is furnished with a tank con- 

 taining a i^ump with an air chamber above the tank, which is attached by gearing to 

 one of the wheels. Underneath the tank are pipes leading to nozzles from which 

 the spray is delivered. As the spraying machine moves along, the vines are picked 

 up by a V-shaped wooden fork and held in such position as to receive the spray 

 with best effect. The machine sprays 3 rows, and the total cost per acre for labor 

 and materials is about S2.50. 



San Jose scale insect: Its appearance and spread in Connecticut, W. E. 

 Britton {Connecticut State Sta. Bui. 135, pp. 14, pis. 5). — A brief account is given of 

 the introduction of the San Jose scale into this country, its discovery and distribution 

 in Connecticut, nursery inspection in the State, legislation with regard to the insect, 

 its life history, description of various stages, food plants, means of distribution, effects 

 on trees, and remedies to be used in combating it. Spraying experiments were made 

 with kerosene, crude oil, and whale-oil soap. In these experiments it was found 

 that crude oil or kerosene in 20 per cent mixture with water, if thoroughly applied, 

 killed the scales without causing any serious injury to the trees. It is not regarded 

 as safe to apply either crude oil or refined kerosene on damp cloudy days. In some 

 localities a solution of whale-oil soap containing 2 lbs. of soap per gallon of water is 

 preferred, but this treatment is more expensive and not quite so effective in destroy- 

 ing the insects as either kerosene or crude oil. Greater difficulty is also experienced 

 in applying whale-oil soap in the form of a spray. For summer treatment it is recom- 

 mended that kerosene be applied in a 15 per cent mixture in water, or whale-oil soap 

 in the proportion of 1 lb. to 5 gal. of water. In fumigating nurseries, the formula 

 for producing hydrocyanic-acid gas as used by the author was as follows: Cyanid 

 potash (97 per cent) f oz.; sulphuric acid (specific gravity 1.83) 1^ oz.; water 1| oz. 

 per 100 cu. ft. of space. This treatment is not certain to kill all scales, but is 

 considered one of the surest methods of destroying them in nursery stock. The 

 illustrations accompanying the bulletin include figures showing infested pears, dis- 



