152 EXPERIMENT STATION EECORD. 



It has been found that the melon aphidid can be controlled by applications of 

 this insecticide made with a barrel pump, equipped with a lead of hose, bamboo 

 rod, and nozzle with bent shank and fine cap. At a strength of 1 : 250 it will not 

 injure melon foliage. A strength of 1 : 500 or 600 is as effective against the 

 aphidid and is recommended particularly when quick results are desired, while 

 a 1 : 1,000 solution is practically as eflBcient and is recommended for use in com- 

 mercial operations. 



" With proper equipment and thorough application, it is possible to kill prac- 

 tically every melon louse on the vines. The material appears to be so destruc- 

 tive to the lice that the finest mist, coming in contact with their bodies, is 

 cajiable of killing them. When the vines are of medium size, about 200 gal. of 

 solution are required for spraying an acre of ' rowed ' melons. Allowing a 

 1 : 1,000 solution, the blackleaf 40 for this amount would cost $2.50. 



"Whale-oil soap and tobacco decoction are fairly efficient for controlling 

 melon lice if applied repeatedly, but do not compare with blackleaf 40 in effec- 

 tiveness or in the ease with which they may be prepared. In the tests at this 

 station, fumigation with carbon bisulphid did not prove to be an efficient or 

 practicable method of controlling attiicks of melon lice. Kerosene emulsion can 

 not be used with safety for spraying muskmelons and cucumbers. Homemade 

 lime-sulphur solution injures melon foliage when used as weak as 1 : 40, and 

 does not control the lice when used as strong as 1 : 20." 



An experiment on killing tree scale by poisoning the sap of the tree, F. 

 Sanford {Science, n. ser., 40 il9U), No. 1032, pp. 519, 520).— It is stated that 

 the cottony cushion scale on a 12-year-old Spanish broom tree, 4 in. in diameter, 

 was destroyed by the author in February by boring a S-in. hole to a depth of 3 

 in. in the trunk and filling it with potassium cyanid. A similar hole bored in 

 an old peach tree and filled with potassium cyanid seemed to increase its vigor. 



The Great Basin tent caterpillar in California, E. C. Van Dyke {Mo. Bui. 

 Com. Hort. CaJ., 3 {1914), No. 9, pp. 351-355, figs. 3).— During the summer of 

 1914 caterpillars of Malacosoma fragilis were found in enormous numbers in 

 the territory about Mt. Shasta. The extensive brush areas found on the south- 

 ern and eastern slopes and to the northeast of the mountain were throughout 

 much of their territory completely defoliated, and presented a brown and seared 

 appearance. The food plants consisted primarily of the thick or broad-leaved 

 Ceanothus {Ccanothus velutinus), or snow-bush, and C. cordulatiis. The so- 

 called "squaw carpet" (C. prostratus), wild cherry, willow, and many culti- 

 vated plants, including the apple, are also attacked by this insect. 



Seasonal variation in the common bollworm (Earias insulana), G. Storey 

 {Agr. Jour. Egypt, 3 {1914), No. 2, pp. 99-102, pis. 2).— A colored plate illus- 

 trating a series of 16 adults which show the natural variation of the species 

 is presented. 



Methods for the destruction of the pink bollworm (Gelechia gossypiella) 

 in cotton seed, L. II. Gough and G. Storey {Agr. Jour. Egypt, 3 {1914). No. 2, 

 pp. 73-95, fig. 1). — The authors describe experiments conducted with mechanical 

 and chemical means for destroying the pink bollworm in cotton. 



The different methods that have been found effective and commercially appli- 

 cable are (1) hot-air treatment, consisting of exposure of the seed to a tempera- 

 ture of between 75 and 94° C. for ten minutes, which did not affect its germina- 

 tion in any way; (2) treatment by poisonous gases, including carbon bisulphid, 

 hydrocyanic acid gas, and sulphur dioxid; and (3) treatment by soaking in 

 cyllin solution 1 : 1.000 for 24 hours. The first two methods can be employed on 

 a large scale at the time of ginning, the third only immediately before sowing. 

 Treatment is not possible when the seed is in the sacks. 



