Harmful Insects

Leaf Miners

Leaf miners are insects that develop and live inside the leaves of plants. Most leaf miners are sawflies, a species of non-stinging wasp. One common exception is the spruce needle miner, which is a moth. The immature (larval) stage of these insects produces the distinctive mines. Adults lay their eggs on the leaves or insert them under the leaf surface. The leaves are injured when the larvae feed on the soft interior tissues so that only the transparent outer leaf surfaces remain.

Although leaf miners destroy the leaf they inhabit, the percentage of leaves affected is usually small. Severe infestations that recur over several years will begin to stress the plant. In the case of birch, stress can be serious because weakened birch trees are vulnerable to the bronze birch borer.

[View Larger Image]	Birch Leaf Miners	[View Larger Image]

To learn more see the attached information sheet by clicking the PDF icon below.

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