Il8 A MANUAL OF FORESTRY 



THE PINE SAWFLY (Diprion simile}. 1 



Dr. W. E. Britton, State Entomologist of Connecticut in 

 1914, first discovered the presence of the insect in the United 

 States. It must have been introduced on nursery stock from 

 Europe, where it is one of the most injurious sawflies. The 

 insect is now established in Connecticut, New York and 

 New Jersey. 



Form of Damage. The larva feed on pine needles and may 

 completely defoliate trees. Probably all species of pine can be 

 attacked. 



Appearance. The insect is most easily recognized in the 

 larva or caterpillar stage. The caterpillars are greenish yellow 

 in color with black head and a double stripe of brown on the 

 back. Their length ranges from one to one and an eighth 

 inches. 



Life History. The eggs are laid by the sawfly in slits along 

 one edge of the needles. From these eggs larva hatch and feed 

 on the foliage. There may be at least two broods of larva in 

 one season. The summer brood of larva make cocoons on the 

 branches of the tree, while the second brood deposit their 

 cocoons in the litter beneath the tree. In the spring sawflies 

 emerge from the cocoons. 



Treatment. No practical method of combating this insect 

 in the forest is known. Several active parasites have already 

 been found in this country. It is still too early to say how 

 injurious the pine sawfly will become. 



ELM- LEAF BEETLE (Galerucella luteold). 



Form of Damage. The elm leaves are skeletonized and this 

 gives the crown of the tree a brown, scorched appearance which 

 detracts greatly from its beauty. If a tree is defoliated two or 

 three seasons in succession it is sure to die. The elms of southern 

 New England, especially those in cities and towns, have suffered 

 tremendously from this pot 



1 See Fifteenth Report of the State Entomologist of Connecticut, p. 118. 



