The Control of Insect Pests and Plant Dlseases. 



591 



Aphis. 



Plum curculio. 



CHERRY. 



Early in the season these dark brown plant-lice curl the termi- 

 nal leaves, especially of sweet cherries. Spray with kerosene 

 emulsion diluted with 6 parts of water or with one of the tobacco 

 extracts. Repeat the application if necessary. 

 See under plum. 



CUCUMBER, MELON AND SQUASH. 



These yellow, black-striped beetles appear in numbers and 



Striped CUCUm- attack the plants as soon as they are up. Plant early squashes 



ber-beetle. as a trap-crop around the field. Protect the vines with screens 



until they begin to run, or keep them covered with Bordeaux 



mixture, thus making them distasteful to the beetles. 



Squash vines are frequently killed by a white caterpillar 



Squash-vine which burrows in the stem near the base of the plant. Plant 



borer. a few early squashes between the rows of the late varieties 



as a trap-crop. As soon as the early crop is harvested, remove 



and bum the vines. When the vines are long enough, cover them at the joints 



with earth in order to develop secondary root systems for the plant in case the 



main stem is injured. 



These dark green plant-lice feed on the undersides of the leaves. 

 Aphis. causing them to curl and wither. Spray with kerosene emulsion 



diluted with 6 parts of water or use one of the tobacco extracts. 

 It is necessary thoroughly to cover the undersides of the leaves; the sprayer, there- 

 fore, must be fitted with an upturned nozzle. Bum the vines as soon as the crop 

 is harvested and keep down all weeds. 



The rusty-black adult emerges from hibernation in the spring 

 Squash and lays its eggs on the underside of the leaves. The nymphs 



stink-bug. suck the sap from the leaves and stalks, causing serious injury. 

 Trap the ad- 

 ults under boards in the spring. 

 Examine the leaves for the 

 smooth shining brownish eggs 

 and destroy them. The young 

 nymphs may be killed with kero- 

 sene emulsion. 



CURRANT AND GOOSE- 

 BERRY. 



In the spring 

 Currant-worm, the small 



green, black- 

 spotted larvae (Fig. 199) feed 

 on the foliage, beginning their 

 work on the lower leaves. A 

 second brood occurs in early 

 summer. When worms first ap- 

 pear, spray with i lb. Paris green 

 or 4 lbs. arsenate of lead in 100 Fic. 199. Currant-worms . 



