Definitely a chestnut thanks to the blooms. Based on the leaves I lean toward a Chinese chestnut. The leaf margin for Chinese chestnuts are toothed but not deeply. American chestnut leaf margins look more like a saw blade. Besides the tree seems not to be affected by the blight. While some large Am. Chestnuts do exist it is more likely this is an Asian relative that is less susceptible to the blight.
Back it if you use it for bow wood or leave it for the wildlife as Dark soul suggested.
