4. Ulmus alàta Michaux. Winged Elm. [Plate 60.] Small to medium sized trees; bark rather closely fissured, grayish or reddish-brown, in appearance like white elm; twigs hairy at first, generally remaining more or less pubescent throughout the season, rarely becoming entirely glabrous before the end of the season, a light brown gradually becoming a gray-brown; branchlets usually begin to develop two thin narrow corky ridges, becoming by the end of the second year 4-7 mm. thick, the year's growth of corky layer a light brown, the older layers a darker brown, the two main corky ridges are on opposite sides of the twigs, and between these there are generally additional corky excrescences, especially on the older branches; leaves oblong-lanceolate or oval, some somewhat falcate, average blades 4-8 cm. long, pubescent on both sides on unfolding, becoming at maturity glabrous or nearly so above, some are rough above at maturity, remaining pubescent until maturity beneath; petioles short, generally 2-3 mm. long, rarely 5 mm. or longer; fruit ripening before or with the unfolding of the leaves; samara 6-10 mm. long, pubescent on both faces.
Distribution.—Virginia west through southern Indiana to southern Missouri, south to the Gulf and west to Texas. In Indiana it is confined to the southwestern part of the State. Gorby's report for Miami should be ignored. It has been reported as far north as Vigo and Monroe Counties by Blatchley, and as far east as Clark County by Baird and Taylor. The author has collected it in Crawford, Dubois, Martin, Orange, Perry, Posey, Spencer and Warrick Counties.
The tree has two rather distinct habitats. In the hill counties it is found on the sides of cliffs, steep slopes or on the top of the ridges with such species as the black, chestnut and scarlet oaks and chestnut. In this habitat it is usually a small scrubby tree with an excessive number of side branches. Such specimens usually have the corky ridges well developed on all of the branches and the tree presents a weird appearance. The second habitat is in the hard clay flats of the southwestern counties. In Warrick County along Big Pigeon Creek west of Boonville I measured a specimen 21 dm. in circumference and I estimated the clear bole at 8 m. It was associated with sweet gum, black gum, white elm, red birch, red oak, etc. It is found throughout this county both in the "flats" and on the sandy ridges. In Posey County it is a frequent tree in the low woods about 10 miles southwest of Mt. Vernon. In these woods it acquires a diameter of 3-6 dm. and is associated with post oak, Spanish oak, sweet gum, shingle oak, etc. It is to be noted that specimens that grow in these conditions and those that acquire a large size do not develop such conspicuous corky branches. A large tree over 6 dm. in diameter was noted in the eastern part of Gibson County growing in low sandy soil which was destitute of corky branches so far as could be seen from the ground. All of the branches examined were free from corky ridges, and only a few corky excrescences were present. The specimen could easily be identified by the leaves. Another large tree 12 dm. in circumference in a black oak woods 4 miles south of Marengo in Crawford County was also free from corky ridges.
This is an interesting tree and requires further study to establish its range in Indiana and to learn its habits. In Jasper, Indiana, it is a frequent shade tree. No doubt the trees were obtained from a nearby woods along the Patoka River where this species is known to occur.
Trees with pith of branchlets chambered; flowers in Indiana species appear before the leaves, the leaves generally with 3 primary veins at the base; staminate flowers usually in clusters, the pistillate solitary or few together in the axils of the leaves, and near the end of the twigs; fruit a globose drupe, sometimes elongated, pulp thin and sweet, frequently remaining on the tree until late winter, relished by birds; stone bony, wrinkled.
Some of the American species of hackberry are very variable. The habitat of the species varies from deep swamps to arid rocky slopes. In fact, a single species as now understood may have a variable habitat. The following variations may be noted on the same tree or on different trees of the same species. The twigs may be glabrous, or pubescent; the leaves may vary in size, shape and texture, leaf margin, and in the roughness or smoothness of the surfaces; the petioles may be smooth or hairy; the pedicels may be glabrous or pubescent, shorter or longer than the petioles; the fruit also varies in shape. Leaves have been seen on the same tree which were smooth above, while others were quite rough above, the difference being due to the exposure to light.
The original descriptions of the species are too short to sufficiently characterize the species, which adds to the confusion. However, C. S. Sargent[45] has recently revised the species and varieties of our area.