Doc, all trees grow according to the conditions in the soil. The same trees can vary in height. Given they have a good water source Cottonwoods will grow more that 35 feet tall for sure. Willows it depends on what type they are, sandbar and Bebb willows wont grow that tall but Weeping and Black willows will. You need a positive ID on your trees. One things for sure a chainsaw makes them all shorter.
