PLATANACEAE 

 Sycamore. Button-wood. Buttonball-tree 



Platanus occidentalis L. 



HABIT. A large tree 70-100 feet high, with a trunk diam- 

 eter of 3-8 feet; commonly dividing near the ground into several 

 large secondary trunks, forming a broad, open, irregular crown 

 of massive, spreading branches. 



LEAVES. Alternate, simple, 5-10 inches long and broad; 

 broadly ovate in outline; more or less 3-S-lobed by broad, shal- 

 low sinuses, the lobes sinuate-toothed; thin and firm; bright 

 green above, paler beneath, glabrous both sides ; petioles stout, 

 puberulous, 1-2 inches long. 



FLOWERS. May, with the leaves; monoecious; borne in 

 dense heads ; the staminate dark red, on short, axillary peduncles ; 

 the pistillate greenish, on long, slender, terminal peduncles ; 

 sepals 3-6, minute; petals 3-6, minute; stamens 3-6, usually 4; 

 styles long, incurved, red. 



FRUIT. October, persistent on the limbs through the 

 winter; brown heads about I inch in diameter, on slender, glab- 

 rous stems 3-6 inches long. 



WINTER-BUDS. Terminal bud absent; lateral buds *A-$i 

 inch long, conical, blunt, lustrous, pale brown ; forming in sum- 

 mer within the petiole of the leaf. 



BARK. Twigs pale green and tomentose, becoming smooth, 

 dark green, finally grayish ; thick, red-brown on the trunk and 

 broken into oblong, plate-like scales, separating higher up into 

 thin plates which peel off, exposing the greenish or yellowish 

 inner bark. 



WOOD. Heavy, tough, hard, rather weak, coarse-grained, 

 difficult to split, light red-brown, with thick, darker colored sap- 

 wood. 



DISTRIBUTION. Lower Peninsula as far north as Ros- 

 common County. 



HABITAT. Prefers rich bottom-lands along the borders of 

 rivers and lakes. 



NOTES. Rapid of growth. Bears transplanting well. 

 Often planted as a shade tree. Fungous diseases disfigure it 

 seriously. 



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