You could, but then when they thawed out, they'd undoubtedly be limp and mushy, and the chemicals that the GSTs need would probably be gone.
Pruning encourages lots of new growth, though, and that's what the Mama butterflies look for to lay their eggs on, so, unless your trees are very small and you scalp them, pruning would be beneficial. It's dangerous to over prune a real young tree, might kill it.
Sherry

Some leaves can last a LONG time in ziploc bags in the fridge. Late last month, I threw out maple, walnut, and sweetgum leaves I put in the fridge months ago. The maple leaves were still good (I KNOW not all maples will do this).

I'd say toss your leaves in the fridge (not the freezer) and see what happens.

Even if the leaves do hold up, I don't know that the GST cats will eat them. Not all caterpillars will use refrigerated leaves. Monarchs have always done it for me. This past autumn, I found that polyphemus, cecropia, and Io would rather starve.

Thanks everyone. These are established trees and will probably go crazy in the spring, so I will not worry. I may try the fridge thing though!! Thx.