The mighty American elm with its distinctive vase shape and strong branches earns the popular vote as the perfect tree. While the wild form is dying out from Dutch elm disease, a host of new selections are being released that show improved resistance to this disease. New varieties of Chinese, or lacebark, elm combine the best of the American elm's graceful shape with lacy foliage and showy bark. Cultivars of the Siberian elm survive the rigorous conditions of the Plains and Mountain states.