Species Responsible
There are two species mainly responsible for defoliation and browning of birch trees in the United States and Canada. In Northern forests, it is the Amber Marked Leafminer, Profenusa thomsoni, which were accidentally introduced from Europe to North America early in this century. The other is the Birch Leafminer, Fenusa pusilla, which is more common in Eastern forests.
Read more about this topic: Birch Leafminer
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