Elms are known for their fast growth rate and high, arching canopies. Elm hybrids are highly resistant to Dutch Elm Disease. Because they’re often grafted onto Siberian Elm rootstock, any sprouts that emerge below the bud union should be pruned back. They naturally grow more than one leader and should be pruned to develop a single leader if desired. A single leader can help prevent splitting with high winds and ice loads. Frontier has the characteristic vase shape of an American Elm with good resistance to Dutch Elm Disease and tolerance of urban conditions. Leaves turn purplish-red in the fall.