I don't know what part of Indiana he is in, but if he is in the southern part it is probably Hazel Alder like I said. However, if he is in the northern part it is likely Alnus incana (Speckled Alder). The wildlife value is similar between the two. I can easily tell them apart by their leaves.
There is a non-native called Black Alder. It gets bigger than the natives. The leaves will also ID it. Going from memory, I don't think it likes the wet spots as much as the natives.
There are other alders I'm less familiar with and I suppose it could be one of those. But, that is an alder in his pic.