INSECTS INJURIOUS TO SHADE TREES 



The elm leaf-beetle^ {Galeriicella luteola) 

 Order — Coleoptera 



Introduced from Europe and first found here in 

 1834 in Baltimore; the beetle is about one-fourth 

 of an inch long, brownish-yellow in color with a 

 dark line along each side of its back; the adults and 

 larvae eat the leaves and defoliate the trees. 



The full-grown beetles hibernate in cracks and 

 crevices, especially in attics of houses, and appear 

 in spring as the leaves are putting out; they lay 

 their orange-colored eggs on the undersides of the 

 leaves; these hatch in 5 or 6 days; the grubs eat 

 the leaves and mature in 15 to 20 days and pupate 

 at the bases of the trees on top of the ground ; in 6 

 to 10 days the adults appear and in New York there 

 is a second generation. 



Control — Spray with arsenate of lead as trees 

 come in full leaf for the beetles and again about 3 

 weeks later for the grubs; use 3 to 4 pounds to 50 

 gallons of water; the Gypsy-moth Commission 

 sprays but once and uses 5 pounds to 50 gallons; 

 they spray as soon as trees come into good leafage. 



The elm leaf-miner ^ (KaliosyspJiinga idmi) 

 Order — Hymenoptera 



The leaf-miner is another European insect but it 

 works on Scotch and English elms; it is a sawfly 

 and the larvae ''blister" and kill the leaves; the 

 adults are small, shining black sawflies, about one- 

 eighth of an inch long. 



1 Herrick — Cornell Univ. Expt. Stat., Bull. 333. 

 Felt— Bull. 20 of the N. Y. State Museum. 



2 Slingerland— Cornell Univ. Expt. Stat, Bull. 233. 

 Herrick— Cornell Univ. Expt. Stat., Bull. 333. 



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