INSECTS INJURIOUS TO MELONS, CUCUMBERS, ETC. 343 



squash and might be destroyed upon it by spraying with pure 

 kerosene. 



Liberal fertilization with quick-acting fertilizers will aid the 

 young plants to make a quick growth and thus outgrow the in jury. 



Growers have long known that if the plants are kept thoroughly 

 covered with some sort of dust that the beetles will not molest 

 them, and various sprays have been used in the same way. To be 

 effective, the plants must be dusted in early morning while the 

 dew is on and all parts of the plant, above and below, must be 

 thoroughly covered. This must be repeated as often as the dust 

 is washed or blown off, or the plant outgrows it. Air-slaked lime 

 mixed with sulfur, tobacco dust, and bug-death have been the most 

 effective, though similar powders will be found beneficial. Bor- 

 deaux mixture has been recommended for this purpose, but seems 

 to have a stunting effect on the young plants. The most valuable 

 repellant seems to be a spray of arsenate of lead 3 to 5 pounds per 

 barrel. This not only repels the beetles better than any other 

 substance tested by Dr. Headlee but also kills many which are 

 forced to feed upon it. Arsenite of lime and zinc arsenite are 

 both recommended by Dr. Chittenden, (I.e.) to be used as is the 

 lead arsenate, either with or without Bordeaux mixture. Most 

 evidence now available indicates that these poisons will pro- 

 tect the vines to a rather limited extent and too much reliance 

 must not be placed upon them. They are of value when used in 

 connection with the cultural methods outlined. The problem 

 of cucumber beetle control is one which needs more investigation, 

 in spite of the fact that the insect has long been known. 



Various repellants, such as kerosene, turpentine, naphthalene 

 or moth balls, and other similar odoriferous substances, have 

 been strongly recommended, but careful tests have not demon- 

 strated their efficiency. 



It is evident that the cleaning up of vines as soon as the crop 

 can be gathered and the destruction of all refuse will deprive the 

 beetles of food in the fall and force them to seek other hibernating 

 places, thus increasing the mortality. 



The spotted cucumber-beetle, Diabrotica 12-pundata Oliv., 

 is found almost always with the striped beetle and injures the 

 plants in the same way. A full account of it will be found in the 

 chapter dealing with insects affecting the corn plant. 



