Birch tree with no seed pods.
My birch tree seems healthy but it had no seed pods on it this year. Does my birch tree have something wrong with it?
Whitman County Washington birch
I wouldn't worry about it. Many trees, including fruit trees, maples, birches, and other trees, have cyclical heavy and light fruit (seed) producing years. If your tree seems healthy, this was probably the "off" year.