View source for Platanus

{{Inc|
Platanus (its ancient Greek name). Platanaceae. Plane-tree. Buttonwood. Ornamental 'trees with handsome dense foliage, often planted as shade and street trees.

Deciduous, with the bark exfoliating in thin plates, but at the base of older trunks the bark is persistent, of darker color and furrowed: stipules conspicuous, usually connate into a tube, with spreading lf.-like margin; petiole with the enlarged base inclosing the axillary bud: lvs. palmately lobed, covered densely with stellate hairs when young: fls. monoecious, in dense globular heads, staminate and pistillate similar, but on separate peduncles; sepals and petals 3-8; staminate with 3-8 stamens, pistillate with 3-8 pistils with elongated styles: fr.-heads consisting of numerous narrowly obconical, 1-seeded nutlets surrounded at the base by long hairs.—Six or 7 species are known in N. Amer., south to Mex. and from S. E. Eu. to India.

The planes are handsome trees with large and palmately lobed leaves and small greenish flowers in drooping heads, followed by similar heads of fruits remaining on the branches during the winter. The smooth light-colored often almost creamy white bark of the branches and limbs, usually mottled by darker blotches of the older bark, which peels off in large thin plates, gives the tree a very characteristic appearance in winter, while in summer the plane-tree, with its large head of dense bright green foliage and with its massive trunk is a beautiful and majestic shade tree. The native P. occidentalis is hardy North and P. aceri- folia and P. orientalis hardy as far north as Massachusetts, while the southwestern and Mexican species cannot be cultivated in the North. From time immemorial, the oriental plane, which was well known to the ancient Greek writers, has been famous for the large size it attains—trunks of 30 feet in diameter and more are reported to exist—and has been planted as a shade tree in western Asia and southern Europe, and today it is still one of the favorite street trees throughout the temperate regions of Europe. It has also been recognized in this country as one of the best street trees, even to be preferred to the native plane, which, unfortunately, suffers from the attacks of a fungus, Gloeo- sporium nervisequum, while the oriental is not injured by it. The plane-trees stand pruning—even severe pruning—well. To what extent they are sometimes pruned in European cities without losing their vitality is shown in an interesting illustration in "Forest Leaves," Vol. III, p. 97. They are also easily transplanted even as larger trees. They grow best in a deep and rich moist soil. Propagation is by seeds sown in spring and only slightly covered with soil and kept moist and shaded; also by cuttings of ripened wood and by greenwood cuttings under glass in June taken with a heel, and sometimes by layers. Varieties are also sometimes grafted in spring on seedlings of one of the species. The stellate hairs of the young leaves when detached by the wind, sometimes float in great quantities in the air and are liable to cause irritation and sometimes inflammation of the mucous membranes of the eye, nose, and mouth. But as this is likely to occur only during a very limited period late in spring it can hardly be considered as a serious objection to the use of platanus as a street tree.
P. vulgaris, Spach, comprises all species of the genus.—P. Wrightii. Wats. Tree, to 80 ft., often divided into several sts.: lvs. usually cordate or truncate, deeply 3-7-lobed, with lanceolate, acuminate, entire or dentate lobes, tomentose beneath or nearly glabrous at length, 6-8 in. long: fr.-heads racemose, rather smooth, each on a short stalk. New Mex. and Aris. to Calif. S.S. 7:329.
The other species, as P. mexicana, Moric., which is sometimes planted as a street tree in Mex., P. Lindeniana, Mart. & Gal., and P. glabrata. Fern., all natives of Mex., are not yet intro.
Alfred Rehder.
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{{Taxobox
| color = lightgreen
| name = ''Platanus''
| image = Plataan_bladeren.jpg
| image_width = 240px
| image_caption = Leaves and fruit of a London Plane
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Proteales]]
| familia = [[Platanaceae]]
| genus = '''''Platanus'''''
| subdivision_ranks = Species
| subdivision = See text
}}

:''"Plane tree" redirects here. In mathematics, "plane tree" refers to a [[tree (graph)|tree]] embedded in the [[plane (mathematics)|plane]].''

'''''Platanus''''' is a small genus of [[tree]]s native to the [[Northern Hemisphere]]. They are the sole members of the family '''[[Platanaceae]]'''.

They are all large trees to 30–50 m tall, [[deciduous]] (except for ''P. kerrii''), and are mostly found in [[riparian]] or other [[wetland]] [[habitat (ecology)|habitats]] in the wild, though proving [[drought]] tolerant in cultivation away from streams.

They are known as '''planes''' in Europe, and as '''sycamores''' in North America. (Outside North America, the name "[[sycamore]]" refers to either the [[fig]] ''[[Ficus sycomorus]]'', the plant originally so named, or the Great Maple, [[Acer pseudoplatanus]].)