24 mains: agriculturai. Kxpe;riment station. 1910. 



Bncciilatrix canadensisella (The Birch leaf Bucculatrix) . 



During- the first week in September the leaves of the white 

 and yellow birch in various parts of the State were much in- 

 jured by the caterpillar of the Birch leaf Bucculatrix. The 

 injured leaves (fig. 19) had much of the green parenchymal 

 tissue eaten away, leaving only the epidermis of one side as a 

 transparent film, and even this was found pierced here and 

 there. Every birch in sight seemed to be infested and had a 

 brown and scorched appearance, visible even at a great distance. 



The full grown caterpillar is less than 34 o^ an inch in 

 length, of slender form, with deep incisures between the round- 

 ed segments. The head is pale brown ; the body, dull pale 

 yellowish green. The first and second abdominal segments each 

 have six pairs of rather long bristles besides a few very minute 

 ones; the bristles of the following segments are somewhat simi- 

 larly arranged. There appear to be no distinct tubercles, nor 

 is there an anal fork. Each abdominal leg has 3 pairs of 

 claws (fig. 36) ; except the anal legs have but one claw each 

 (fig. 37). The palpi of the second maxillae are slender, each 

 provided with long bristles. The other mouth parts are as 

 figured (33-35)- 



The molting cocoons are small, circular, white, silken patches 

 in which the larva lies curled up and may be found on the sur- 

 face of the leaf (fig. 19) and also on the under side of twigs 

 and branches. When the larva has attained its full growth the 

 true pupal cocoon is formed. This is an oval yellowish body 

 with flat base and with 5 or 6 sharp longitudinal ridges. These 

 cocoons have been found on the twigs and leaves but as com- 

 paratively few are present there it is evident that the greater 

 number of larvae pupate elsewhere. The moths which have a 

 spread of wing of ^ of an inch have dusky wings crossed by 

 several silvery white bars. They appear in early spring. While 

 the larvae attack the Birch by preference we have found them 

 on Red Oak also. 



For ornamental trees, a weak arsenical spray applied early in 

 August has been recommended. (Lot 793.) 



Gypsy and Brown-tail Moths. 



On account of the seriousness of the Brown-tail Moth and 

 Gypsy Moth situation these two insects should be constantly 



