Apple Leafminer Apple Leafminer Apple leafminer, Lyonetia prunifoliella , has become fairly common in young, nonbearing trees since in the 1980s, but has not resulted in economic injury. Description and life cycle Adults are similar to the spotted tentiform leafminer, but larvae make a winding linear mine that widens into a blotch mine on the upper surface of the leaf. Frass ejected from the mine through holes chewed in the lower epidermis is commonly seen hanging from the mine in threads. Portions of the leaf beyond the mine frequently become chlorotic.
Most infestation is in leaves on succulent shoots and sprouts.
This leafminer does not appear to be economically damaging.