PLANERTREE

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Planertree

Planertree


PLANERTREE
(Planera Aquatica)

This tree is a first cousin of the elms, but it is no more an elm than a hackberry is an elm. It is a member of the family but is of a different genus, and it is the sole representative of its genus in the known world. There is only one kind of planertree, with no nearer relatives than the elms on one side and hackberry, sugarberry, and palo blanco on the other. Except those kinsfolk, it is alone on earth. The name is in honor of Johann Jacob Planer, a German botanist whose efforts did much for science nearly two hundred years ago. The name of the species aquatica, recognizes the tree’s habit of growing where water is abundant. It is a swamp species, or rather, it prefers situations subject to periodic overflow. It looks like an elm, and that has led people to call it water elm. That is the name by which it is usually known in Florida. In Alabama it is called the American planertree, which is an unnecessary restriction, since there is no planertree except this one. The Louisiana French gave it the name plene, and the abridgement of its name is yet heard in that state. In North Carolina it has acquired the name sycamore, but without good reason. It does not look in the least like sycamore.

It has the leaf of an elm, and it resembles that tree in bark, and somewhat in general form. The layman detects the first important difference when he examines the seeds. Those of the elms have wings, but the planertree’s are without those appendages, and they would be useless if it had them, unless they were as large as the parachute of the basswood seed. The planertree bears a sort of nut, a third of an inch long, and too heavy to be transported far on the ordinary membranous wings of tree seeds. Water is doubtless the principal agent in carrying the seeds from place to place. Probably few of them are transported far, because the water about the trees is generally stagnant; and, besides, the species does not seem to be extending its range or increasing in numbers.

The planertree has a history. If the terms which the Roman historian Tacitus applied to people, could be applied to trees, it might be said of this species, as he said of certain tribes: “The cowards fly the farthest and are the last survivors.” The planertree is now found only in certain southern swamps, from North Carolina to Florida, and west to Missouri and Texas. In former periods, as is shown by the records of geology, there were several species, and they had a wide range over portions of the northern hemisphere. They appear to have been a strong group of trees, able to hold their ground with the best inhabitants of the forest. They were in the Rocky Mountains, and far north in Alaska. They were in Europe also, or were represented there by some very similar species.

For some reason which is not definitely known, they lost out when competition with other trees became keen, and in the course of long periods of time they disappeared from their former ranges in the North and West. They took to the swamps, just as the tribes of which Tacitus spoke, took to the morasses when they could no longer face their enemies on open ground. It was a far cry from Alaska to the Chattahoochee swamps in Florida, yet that was where A. H. Curtis and Charles Mohr went to procure typical planertree specimens for the tests which Sargent made of American woods.

It has been suggested that tree species which have lost out in competition for ground, have been those which were at some decided disadvantage in the matter of getting their seeds properly scattered and planted. The case has not been proved, because there are as many facts and as much argument against that hypothesis as for it. The bigtrees of California are a noted example of a species which lost out and retreated to a corner, yet their seeds fly like birds. Plainly, something besides winged seeds is needed to keep the species in the fight. However, it is not difficult to see that the planertree, with wingless seeds and of so little use as food that no bird or rodent will carry them or bury them, has been much handicapped in the long contest which has crowded it from the arctic circle to the cotton belt.

It has the habits of the subdued and conquered tree. It has adapted itself to swamps where few species can grow, and where competition for light and room is reduced to a minimum. Yet, even there, it is content to take the leavings of more ambitious species. The crowns make little effort to rise up to the light, for which many other trees battle during their whole existence. The planertree’s low, broad top of contorted branches places it perpetually in the shade of any other trees which overtop it.

The wood of the planertree is lighter in weight, poorer in fuel value, weaker, and more brittle than the poorest of the elms. The annual ring lacks the rows of large open pores common in all the elms, but it has many small pores scattered through the whole year’s growth. It is not easy to note a difference between the springwood and that which grows later. The wood is soft, light brown in color, and the nearly white sapwood is thick. It is often, perhaps generally, a tree of fairly rapid growth, and since it does not reach large size, it is probably short-lived, but exact information along that line is lacking.

The tallest trees seldom exceed a height of forty feet and a diameter of two. It is evident that a tree of that size and form does not tempt the lumberman to much exertion to procure it. An examination of reports of sawmill operations and of the utilization of woods by shops and factories in the southern states has failed to find a single instance where the planertree has been reported in use for any purpose whatever. Doubtless, trees are sometimes cut and the lumber gets into the market, but not under its own name. The species is interesting for reasons other than that it ever has had or ever can have a place in the country’s lumber industry.

Wing Elm (Ulmus alata), which is the smallest of the elms, is plentifully supplied with names, but in most parts of its range it is known as wing or winged elm. It is also called wahoo or wahoo elm, and the West Virginians have named it witch elm; the North Carolinans refer to it often as simply elm; from Florida to Texas some call it cork elm; in Alabama it is water elm; in Arkansas mountain elm; while in other regions it is corky elm, small-leaf elm, and red elm. Some of these names are self-explanatory. Wing elm does not relate to a winged seed, but to winged twigs. That characteristic of the tree is very prominent. The wings consist of flattened keels along opposite sides of the branches. A twig no more than a quarter of an inch in diameter may be decorated with wings half an inch or more wide, making the twig four or five times as wide as it is thick. As the twig enlarges, the wings do not broaden in proportion. The lowest branches and those nearest the trunk are most generously furnished with wings. They appear to be entirely ornamental, for it is not known that they serve any useful purpose. The growth is different from those which give cork elm its name. The latter occur on the large branches, often in the form of isolated protuberances, but the wings are fairly continuous for a foot or more, except that they terminate abruptly at the nodes, but recommence immediately after. Branches less than a year old seldom have wings. The name wahoo appears to have lost its etymology if it ever had any. Dictionaries tell what it means, but they shy at its origin. It is a southern word which is applied to this elm, and also to other trees, and occasionally it means a fish instead of a tree. Some would trace it to the cry of an owl, others to a name in Gulliver’s Travels, with a slight change in spelling.

Wing elm at its best is about fifty feet high and two in diameter; but much of the stand is small. The best occurs west of the Mississippi river. The range extends from Texas to Virginia, south to Florida, and north to Illinois. In Texas it is a fairly important wood in furniture factories, the annual supply being about a million feet. It is used by turners for table legs. In an investigation of the uses of the wood, the same difficulty is encountered that makes difficult a study of the uses of all the elms—conflict and uncertainty of names. There are few regions in the hardwood areas of this country which produce one elm and no more; and after all practical means of identification are resorted to, there is often doubt and uncertainty concerning the exact species of elm lumber found in use. Fortunately, it generally makes little difference, because anyone of them is good enough for ordinary use. Wing elm is extensively planted for shade along the streets of towns in the lower Mississippi valley, but more frequently on the west side of the valley. When the trees grow in the open they develop broad crowns, and the branches, even of comparatively small trees, are long enough to reach well over the sidewalks, and cast satisfactory shade. The dark-colored winged twigs add much to the ornamental value of the street trees.

Fremontia (Fremontodendron californicum) is not botanically in the elm family, but it is popularly known as slippery elm in the region where it occurs, and for that reason it is here given place among the elms. It is known also as leatherwood. It is a California species, ranging among the lower mountains and higher foothills in dry, gravelly soils, from the Mexican boundary five hundred miles northward in the state. The mucilaginous inner bark tastes like that of the true slippery elm. The shape of the leaf much more resembles sycamore than elm; and it is an evergreen. It bears a bright yellow, roselike flower, and the seeds are small, reddish-brown. The wood is fine grained, clear reddish-brown, with thick, whitish sapwood. It is very soft. The tree attains its largest size among the foothills of the Sierra Nevada mountains, but even there it is too small to have much economic value, seldom exceeding thirty feet in height and a foot in diameter. Its most important use is as a forage plant for cattle and sheep. In that particular it resembles slippery elm in northern woods. The tree is occasionally planted in the eastern states and in Europe for ornament. In its native range it grows slowly.

Planertree branch

                                                                                                                                                                                                                                                                                                           

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