ENGLISH: ILLINOIS TREES: THEIR INSECT ENEMIES 



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Leaf Miners, fig. 37.— Leaf miners, larvae of tiny moths, 

 flies, sawflies, and small beetles, feed between the upper and 

 lower surfaces of the leaves of oaks and many other shade trees, 

 where they produce serpentine mines and blotches. Usually the 

 female places her eggs on leaf surfaces, and each young larva, 

 soon after it is hatched, bores into the leaf and proceeds to tunnel 

 in various directions. If a mined leaf is placed in front of a bright 

 light before the mine has been abandoned, the small larva that 

 did the damage can be seen between the two leaf surfaces. 



Fig. 37.— Leaf miners: damage to oak leaves. Very small larvae of 

 several species of insects "mine" the leaves of oaks and other trees and de- 

 stroy the tissue between the upper and lower leaf surfaces. 



