Leaf mines

HOLLY LEAF MINER - This leaf miner can be found on most species of holly. There are four species of agromyzid flies in Pennsylvania that mine holly foliage. The adult leaf miner lays eggs into the underside tissue of newly formed leaves causing tiny blisters on leaf bottoms. The larvae mine into the leaves and remain for months where it overwinters. Each mine has one larva. The mine eventually broadens into a blotch that contains the pupa. For small infestations hand picking of mined leaves is an effective control. For heavier infestations apply a registered formula in early May.