I got my leafminers from Missouri about 4 years ago.
It was a fall order, and while cleaning the plants for planting I found some pupae inside the leaf bases.
I think if you're going to strip leaves in order to control leafminer, it might be best done in the late fall, after the larvae have pupated for the winter, the dormants are resting, and the evergreens and semi's aren't going to be too affected by leaf loss. It would be a good opportunity to freshen up the garden. The pupae I saw were inside the leaves, at their base, close to the crowns.
