PLATANUS 



PLATANUS 



1367 



size it attains— trunks of 30 ft. diameter and more are 

 reported to exist— and has been planted as a shade tree 

 in W. Asia and S. Europe, and to-day it is still one of 

 the favorite street trees throughout the temperate re- 

 gions of Europe. It has also been recognized in this 

 country as one of the best street trees, even to be pre- 



1846. Plane-tree -Platanus occidentalis. 



ferred to the native Plane, which, unfortunately, suffers 

 from the attacks of a fungusi, Glcfosporium 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. 3, p. 97. They are 

 also easily transplanted even as larger trees. They grow 

 best in a deep and rich, moist soil. Prop, by seeds sown 

 in spring and only slightly covered with soil and kept 

 moist and shady; 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 occa- 

 sionally grafted in spring on seedlings of one of the 

 species. The stellate hairs of the young Ivs. when de- 

 tached by the wind, sometimes float in great quantities 

 in the air and are liable to cause irritation and some- 

 times inflammation of the mucous membranes of the eye, 

 nose and mouth. But as this is likely to occur only dur- 

 ing 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. 



Six or 7 species of Platanus are known in N. America 

 south to Mexico and from southeast Europe to India. 

 Trees with the bark exfoliating in thin plates; 

 only at the base of older trunks the bark is 

 persistent, of darker color and furrowed. 

 Stipules conspicuous, usually connate into a 

 tube, with spreading leaf-like margin; peti- 

 ole with the enlarged base inclosing the ax- 

 illary bud: Ivs. palmately veined, covered 

 densely with stellate hairs when young: fls. 

 moncecious, in dense, globular heads, stami- 

 nate 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, one-seeded 

 luitlets surrounded at the base by long hairs. 



occidentalis, Linn. Buttonwood. But- 

 TONBALL. American Plane-tkee. Also 

 wrongly called Sycamore. Figs. 1846, 1847. 

 Large tree, attaining 130 or occasionally 170 

 ft., with a round-topped oblong or broad head 

 and with a trunk 10 ft. or exceptionally more 

 in diam., often of considerable height: bark 

 of limb and branches of very light often al- 

 most creamy white color, at the base of the 

 trunks dark brown, fissured: stipules large, 

 with toothed margin : Ivs. as broad or broader than 

 long, truncate or cordate, rarely cuneate at the base, 

 usually 3-, sometimes 5-lobed, with shallow sinuses; 

 lobes shorter than broad, coarsely toothed or entire. 



floccose-toraentose when young, at maturity only pubes- 

 cent on the veins beneath, 4-9 in. broad: fr. -heads soli- 

 tary, rarely in 2's, on 3-G-in. long peduncles, about 1 in. 

 across or more, comparatively smooth at length; nutlets 

 with obtuse apex, with the rest of the style one-six- 

 teenth inch long or shorter. May. Maine to Ontario and 

 Minn., south to Fla. and Tex. S.S. 7:3'2(;, 327. G.F. 

 2:354, 355; 9:55. Em. 1 :201, 2G3. Gng. 4:343. Mn. 3, p. 

 09; 5, p. 205, 209. — The most massive and perhaps the 

 tallest of all deciduous trees of N. America and an excel- 

 lent street and park tree where it is not injured by fun- 

 gous diseases. There are several vars. in cultivation: 

 Var. HispAnica, Janko (P. Hispdnica, Lodd.). Lvs. 

 large, 3-5-lohed, with very shallow sinuses, coarsely 

 toothed, usually cordate at the base. Gn. 1, p. 588; 

 20, p. 370. Var. pyramidalis, Jaen. (P. pyramiddUs, 

 Bolle). Of pyramidal habit: lvs. usually 3-lobed, often 

 longer than broad, with usually rounded base. Var. tu- 

 bifera, Jaen. (P. siiperba, Hort.). With very conspicu- 

 ous elongated, tubular stipules. There are also some 

 forms with variegated lvs. Var. Siittneri, Hort., with 

 the lvs. spotted and marked white, and var. aureo-vari- 

 egata, Hort. (var. KelseyAna, Jaen.), with yellow varie- 

 gated leaves. 



orientdilis, Linn. Oriental Plane. Tree, to 80 ft., 

 with usually very broad and round head on a compara- 

 tively short trunk : bark of dull grayish or greenish 

 white color; stipules small, usually with entire margin: 

 lvs. usually broadly cuneate at the base, deeplj' 5-7- 

 lobed, rarely 3-lobed, with the sinuses reaching almost 

 to or below the middle; lobes longer or much longer 

 than broad, coarsely toothed or entire, glabrous or 

 nearly so at maturity, 4-8 in. long: fr. -heads 2-4 on long, 

 drooping stalks, bristly, the nutlets narrowed at the 

 apex into a persistent style to 2 lines long. Mav. S. E. 

 Eu. to India. G.F. 4:91. G.O. III. 23:25, 27. Gn. 1, p. 

 550; 20, p. 3G9, 371, 373. — A variable species, of which 

 the most important forms are the following: Var. aceri- 

 folia, Ait. (P. acerifolia, Willd. P. intermedia, Hovt.). 

 Lvs. less deeply lobed, the sinuses rarely reaching be- 

 low the middle; lobes usually 5, the middle one only 

 little longer than broad: fr. -heads usually in 2's. Gn. 

 1, p. 588; 20, p. 371 and probably 1, p. 486 and 20, p. 370 

 (as P. occidentalis). This form resembles in foliage 

 the American Plane, and is also of more pyramidal habit 

 than the Oriental Plane, which in its typical form has 

 a broad head, with wide-spreading branches deeply 

 divided, 5-7-lobed lvs., and the fr.-heads often in 3's 

 and 4's. It is often considered a distinct species, and 

 some have ventured the opinion that it may be a hybrid 

 between P. occidentalis and P. orientalis, as it is in 

 some characters intermediate between the two, but the 

 fr. does not differ from that of the latter. The var. 



1847. Platanus occidentalis (X 30. 



acerifolia, which is the so-called London Plane, seems 

 hardier and is more generally planted under the name 

 of the Oriental Plane than the typical P. orientalis. 

 Var. digit^ta, Janko (P, umhra.culifera , Hort , var /o- 



