Insefts and Diseases. 1 69 



exist ; in the extreme northern parts of the Union, it is not formida- 

 ble ; but on approaching the Middle States, although the bushes 

 grow vigorously and set abundant crops of young fruit, the latter 

 become covered with a thick brown or grey mildew or scurf, which 

 destroys their value. 



Manuring, high cultivation, and pruning, will in some cases prove 

 sufficient to prevent mildew. This may be assisted by the cautious 

 application of salt, either thinly over the soil, or directly upon the 

 plant ; in the latter case, the solution should be so thin that the 

 saline taste may be just perceptible. Shading by a thick coat of 

 salt-hay, appears to be an efficient remedy. It should be spread in 

 a layer of several inches or even a foot in thickness, crowding it 

 down to make room for the branches. This should be done in 

 spring. 



Mildew of the Grape. This always attacks vines of the exotic 

 grape after they have grown a few years in open air. In unfavora- 

 ble seasons a similar disease assails many varieties of the American 

 grape. The best general preventive appears to be, keeping the 

 vines thrifty and vigorous by pruning and cultivation ; and the 

 admission of light and air by a sufficient thinning and distance in 

 planting. The best remedy appears to be dusting with sulphur. 

 This should be applied late in spring and early in summer, on the 

 first appearance of the disease, and repeated at intervals of a fort- 

 night so long as may be necessary. It may be applied by an instru- 

 ment similar to a hand-bellows (without a valve below), which drives 

 the sulphur-dust, fed from a box on the upper side, through a large 

 tube or nose terminated with vvire gauze. 



The Rot in the grape has proved a formidable disease, especially 

 in the south-west. It commences with dark-colored spots on the 

 young fruit, spreading afterwards over the berry, causing it either 

 to fall or to shrivel while adhering to the branch. No efficient 

 remedy has been devised, and the only satisfactory preventive is the 

 selection of such varieties as are not liable to the disease. 



ADDITIONAL NOTES ON INSECTS. 



THE APPLE WORM, OR CODLING MOTH (p. 153). This insect 

 has become the most formidable enemy of the apple in the United 

 States. It does much damage to the pear, but does not attack 

 stone-fruit. In many orchards it ruins nearly the whole crop, and 

 is now penetrating into States beyond the Mississippi. The moth, 



