﻿Trees of New York State 229 



PLATANACEAE 



Platauus occidentalis L. 



Sycamore, Buttonwood, Plane Tree 



Habit — The most massive tree of eastern Xorth America, commonly 50-100 

 feet in height with a trunk diameter of 3-8 feet, under optimum condi- 

 tions sometimes 150-170 feet tall with a trunk diameter of 11 feet. Bole 

 erect or often declined, tapering, continuous through the oblong head or 

 soon breaking up near the ground into several large, massive limbs to 

 form a broad, rounded, irrregular crown. 



Leaves — Alternate, broadly ovate or orbicular, 4-7 inches in diameter, 

 truncate, slightly cordate or cuneate at the base, shallowly 3-5 lobed and 

 palmately veined, the lobes broad, acuminate, sinuately dentate with 

 remote acuminate teeth, or entire. At maturity the leaves are thin, firm, 

 smooth and bright green above, paler and white-woolly below on the 

 principal veins, borne on stout petioles 1-2% inches long. 



Flowers — Appearing on the gro\\i:h of the season during May when the 

 leaves are about one-fourth growni, monoecious, borne in capitate heads. 

 Staminate heads dark red, about % of an inch in diameter, borne axillary 

 on long, stout, woolly peduncles. Perianth of 3—5 minute sepals and 

 petals. Stamens 3-6, nearly sessile, ■\\-ith yellow, clavate anthers. Pistil- 

 late heads pale green tinged Avith red, about ^4 of an inch in diameter, 

 borne terminally on long, stout, woolly peduncles. Perianth of 3--6 

 sepals and petals. Pistils as many as the sepals, superior, surrounded 

 by a like number of spatulate staminodia, each consisting of an ovate- 

 oblong ovary surrounded at the base by long pale hairs which persist in 

 fruit, and long, tapering, bright red styles stigmatic along the ventral 

 suture. 



Fruit — A spherical, brown, aggregate head, about 1 inch in diameter, borne 

 on a long, smooth peduncle 21/2-6 inches long, consisting of many closelj'- 

 compacted, clavate, 1 -seeded nutlets, each cro\\^led by the remains of the 

 persistent style and furnished wdth a ring of bristly hairs about the base. 

 The heads mature in the late autumn but persist on the branches into 

 the ■winter and following spring. 



Winter characters — Twigs rather stout, smooth, somewhat lustrous, zigzag, 

 enlarged at the nodes and encircled by stipule-scars, dark orange-brown, 

 at length light gray. Pith white and rather broad. Terminal bud absent. 

 Lateral buds divergent, conical, obtuse, lustrous, reddish brown, %-% 

 of an inch long, subpetiolar until leaf-fall. Mature bark at base of 

 trunk thick, dark brown, deeply furrowed with broad ridges Avhich peel 

 off as dark brown scales. On young trunks or large limbs the bark is 

 much thinner and flakes off during the early summer in large plates, 

 exposing a Avhitish, yellowdsh, or greenish inner bark. 



Habitat — Thrives best along river banks and on rich, moist bottom-lands 

 but AAill grow' in rather dry soils. Attains its best development in the 

 Ohio and Mississippi River basins. 



Range — Southern Maine westward through southern Ontario and Michigan 

 to Minnesota and Nebraska, south to Florida and eastern Texas. Zones 

 A, B and C. 



Uses — A timber species of secondary importance. Wood hard, heavy, weak, 

 coarse-grained not durable, light broAvn with pale yellowish sapAvood. 

 Used for crates, tobacco boxes, butchers' blocks and for interior finish as 

 quartered sycamore. Occasionally planted ornamentally. 



