The Northern Catalpa grows 40-60 Feet and has an interesting twisting trunk and branches. The flowers on this tree are bright white and attract hummingbirds. Another great feature are their giant heart-shaped leaves that turn yellow in the fall. They also have dangling bean-like seed pods that add a little extra flair. The Northern Catalpa is widely considered to be one of the most beautiful landscape trees. This unique and hardy tree is a fast grower that finds a home in parks and yards throughout the country.