River Birch First Paper Bark Losing Juvenile Bark

My river birch in the backyard are beginning to lose their red juvenile bark, and beginning to peel into papering adult bark. It's starting at the bottom and moving up the tree. I'd say it's about 8 inches high so far.

The trees quickly put on about 1 1/2 feet of new vertical growth this summer, and now they're getting fatter trunks. I'm hoping for some more vertical growth before the Fall really sets in.

First paper bark on a young river birch, losing its red juvenile bark