﻿Trees of New Yoyk State 203 



ULMACEAE 



Ulmus aniericana Ij. 



White Elm, American Elm 



Habit — The largest of the elms. A tree usually 60-100 feet in height with a 

 trunk diameter of 2-5 feet, under optiiuuni conditions sometimes 140 feet 

 tall with a crown spread of .10-70 feet. In the open the crown is very 

 variable. Well known varieties are the vase form, the umbrella form and 

 the feathered form. Bole tall and straight, bearing a high crown of grace- 

 ful, drooping branches, or short and often buttressed at the base and soon 

 breaking up into large, ascending limbs. 



Leaves — Alternate, oval to obovate-oblong, 4-6 inches long, 1-3 inches wide, 

 acuminate at the apex, rounded and inecjuilateral at the base, coarsely 

 doubly serrate, at maturity dark green and glabrate and slightly scabrous 

 above, paler and soft pubescent or quite glabrous below, with prominent 

 midrib and parallel secondary veins, borne on stout ])etioles about ^4 of an 

 inch long. 



Flowers — ^ Perfect, pedicelhite, appearing before the leaves during April and 

 May in long pedunculate, 3-4 flowered inflorescences from the axils of the 

 inner scales of separate flower-buds, each bud giving rise to 5-8 fascicles. 

 Calyx campanulate, reddisli green, puberulous, 7-9-lobed, the lobes short, 

 rounded and eiliate on the margins. Stamens as many as the corolla lobes, 

 exserted, with slender filaments and red anthers. Pistil with light green, 

 compressed, 2-celled ovary surmoiinted by 2 green styles v.liite papillii+e 

 along the inner surface. 



Friiit — A 1-seeded, oval to obovate-oblong, long-stalked, pale gre.M saiu.'iri, 

 about % of an inch long, marked by a horizontal line indicating the union 

 of the 2 caipcls, smooth aside from the eiliate Uiiirgiu, ripening as-' tlie 

 leaf-biids begin to mifold. Wing reticulate-venulose, ciiiate on the mar- 

 gin, deeply notched at the apex, the teeth incurved and overlapping. 



Winter characters —- Twig slender, krticellate, giabious or puberulous, ligiit 

 reddish brown, at length dark brown or ashy-gray. Terminal bud absent. 

 Leaf-buds ovate, acute, chestnut-brown, about % of an inch long. Flower- 

 buds slightly larger, borne below the leaf-buds. ^T-iture liark tlii<-k. 

 rough, ashy-gray, irregularly divided by deep fipsmcs int(^ iToad. scaly 

 ridges. 



Habitat — Typically a bottom-land species, preferring moist, rich alluvial 

 soils along stream courses and lakes but thriving well on upland sites, 

 usually in admixture with other species. Not exacting as to soil require- 

 ments. 



Bange — Newfoundland west througli southern Canada to the eastern sl()i)es 

 of the Rocky Mountains, south to Florida and eastein Texas. Tlie most 

 widely distributed of the American elms. Zones B, C, and D. 



Uses — A valuable species. Wood heavy, hard, strciig, coarse-grained, tougii, 

 difficult to split, light brown with wide, paler sapwood. Widely used for 

 cheese boxes, cooperage, and a. variety of purposes including planking, 

 wheel hubs, etc. The tree with its various forms is valuable as a shade 

 and ornamental s]iecies along avenues and highways. 



