New York Agricultural Experiment Station, 3G5 



attack the blossoms as well as the fmit. Under conditions favor- 

 able to the disease at the blossoming season it may thus cause great 

 damage to the crop. The manner in which it destroys the fniit of 

 plums is illustrated in Plate XII, Fig. 1. 



Leaf Blight. — This disease also infests cherries and other stone 

 fruits. Its appearance on plums difiers somewhat in general from 

 its appearance on cherries, in that while the tissue of some cherry 

 leaves does not readily break away and drop the infested portion 

 out, as illustrated in the largest leaf in Plate I, Fig. % ; in plums the 

 diseased tissue is more liable to drop out, leaving the leaf riddled 

 with holes as a result of the attacks of the fungus, as illustrated by 

 the smaller cherry leaves in Plate XII. 



The treatment of this disease is discussed under cherries, see 

 p. 352. 



CuKCULio. — The curculio does not confine its attacks to plums, 

 but it usually infests plum orchards, and if left unmolested, often 

 destroys an entire crop. 



The mature insect is a small, curiously formed, gray beetle. It 

 passes the winter under the bark of trees, or under rubbish, and 

 comes forth early in the spring to deposit its eggs in the young 

 fruits commencing as soon as they are formed. It does this by 

 puncturing the tissue and inserting the egg. After the ^^^^ is 

 deposited, the beetle cuts a crescent-shaped groove around one side 

 of the puncture, evidently to prevent the growing tissue from 

 crushing the egg. The eggs hatch in a few days, when the Httle 

 worm, or larva, at once commences to feed on the fruit, causing 

 much of the infested fruit to fall while still young, and that which 

 remains on the tree ripens prematurely and soon decays. 



Remedies. — It has been found that the beetles' manner of pro- 

 tection is to fall to the ground when disturbed. Here they curl up 

 so as to resemble bits of bark. Advantage is taken of this habit in 

 fighting the insect by a process known as jarring. The trees are 

 jarred by three or four strokes with a padded crutch or mallet, and 

 the insects are caught on sheets spread underneath the tree and 

 destroyed. Where only a few trees are to be treated the sheets 

 are laid on the ground. But when large orchards are to be treated 

 the sheets are stretched over a light frame, so that they are con- 

 stantly extended, and no time need be consumed in stretching them 

 into position after the tree is reached. One form of these extended 

 sheets for catching the curculio is made by Mr. Henry Lutts, 



