284 THE PEACH. 



mer till autumn, at the foot of the tree, its exceedingly 



minute, whitish eggs, 

 which soon hatch, and 

 the larvae or worms en- 

 ter the bark. The next 

 season they encase them- 

 selves in a saw-dust-like 

 cocoon, in their holes 

 under the bark; and 

 emerging in the perfect 

 insect, lay their eggs and perish. The perfect insect is very 

 rarely seen, but is easily obtained by enclosing the pupa, 

 fig. 234, b, c, which is readily obtained in summer at the 

 roots of neglected trees, beneath a glass, or in a gauze case. 

 As this insect confines itself to the bark, its destruction is 

 very easy. It rarely happens that trees are completely de- 

 stroyed by it, except they be small; death can only take 

 place when the tree is girdled. Timely care will prevent 

 this ; the evil in fact is only to be dreaded by negligent 

 cultivators. 



The disease termed the yellows is truly formidable. It is 

 peculiar to the peach and nectarine. It has destroyed whole 

 orchards in portions of the country, and for a time induced 

 the entire abandonment of the peach culture in certain lo- 

 calities. 



The cause of this malady has not been satisfactorily as- 

 certained. According to conjecture, it has arisen originally 

 from exhaustion by deteriorated soil, overbearing, and neg- 

 lected pruning and bad cultivation. But whatever may have 

 been its origin, it appears at present, to be chiefly commu- 

 nicated from diseased trees. It is quickly induced by in- 

 serting the bud from an affected tree into a healthy stock. 

 It spreads by contact with diseased roots ; a knife used in 

 pruning the tree will infuse the poison if used on another. 

 It appears to be communicated without actual contact, the 

 healthy branches nearest a diseased tree being usually first 

 attacked. It is also probable that the stones from diseased 

 trees cause its development after a few years growth. Its 

 highly contagious nature is indicated by the equal facility 

 with which young and vigorous trees and old and feeble 

 ones may be inoculated by contact. 



