River Birch Has Thin Foliage On Top Half

Question From: K. Michelson - MINNESOTA
Q: Our river birch is six years old. It has always looked fine and is growing well. However, right now the bottom half looks fine --full with lots of leaves, but the top half looks very thin--a lot less leaves. All I know how to do is give it more water, which I am doing right now. Help! Thanks

A:
Two issues come to mind. Soil pH, river birch require acidic soil. Compacted soil might also be an issue. I suggest you get an on-site inspection from a certified arborist. Go to www.tcia.org
and enter your zip code in the finders box. Best Nancy