68 MAlNli AGKICULTURAI. DXPIIRIMENT STATION. I906. 



That the pest may be held in check was plainly demonstrated 

 by the work of the Station during the last invasion, A large 

 orchard of Baldwins which was sprayed with Paris green when 

 the caterpillars first appeared and twice afterwards, was almost 

 free from injury, while adjoining trees, not sprayed, were com- 

 pletely defoliated, and never recovered from the injury. The 

 accompanying cuts represent the condition of the two orchards 

 late in June. 



Similar results have repeatedly been obtained in fighting the 

 canker worm. It is highly important, however, that, for either 

 of these pests, spraying be done just as soon as the leaves begin 

 to unfold, and again in about a week or ten days. After the 

 larvae become half grown, spraying is not always effective. 



Another precautionary measure to be borne in mind, in deal- 

 ing with the forest caterpillar, is to prevent migration from tree 

 to tree, and from forest trees to the orchard trees. This may be 

 effected by placing a band of tarred paper about the trunk of the 

 tree and smearing this with a thick coating of equal parts of lard 

 and sulphur. It is very important that this mixture be not 

 placed directly on the bark of the tree, as injury almost invari- 

 ably results. 



The method here noted was used with remarkable success in 

 the orchards above mentioned. The caterpillars gathered by 

 the hundred beneath the band, but would not cross the line, and 

 were readily disposed of by means of a swab dipped in a very 

 strong solution of washing powder. The masses of caterpillars 

 upon the limbs were destroyed in the same way; those that 

 escaped by dropping to the ground being stopped by the bands, 

 and then killed as above. 



oyste;r-she;li, bark lousi:. 



An insect which is nearly as destructive as the dreaded San 

 Jose scale, is annually doing thousands of dollars worth of dam- 

 age in the State without the slightest notice on the part of farmer 

 or fruit grower. This insect — the oyster-shell bark louse — is so 

 familiar, and yet so inconspicuous, that it is usually overlooked. 

 The insect is fully described in Bulletin 56 of this Station, to 

 which the reader is referred. It frequently is the unsuspected 

 cause of the stunted, sickly appearance of certain trees to be 

 found in almost every orchard. The mature form, shown in 



