The Poplars 



shelter belts. It is a hardy tree of excellent habit, compact 

 and erect, but not too narrow for shade. It is easily propagated 

 and transplanted, and grows rapidly. The tree is handsome, 

 winter and summer. It has all the good points of the Carolina 

 poplar, and lacks its fault of becoming so soon an unsightly 

 cripple. 



The Black Cottonwood (P. irichocarpa, Hook.) is the giant 

 of the genus, reaching 200 feet in height and 7 to 8 feet in trunk 

 diameter. It is tall and stately, with a broad, rounded crown 

 supported upon heavy upright limbs. One of the beautiful 

 sights of the Yosemite Park is the autumnal gold of black cotton- 

 wood groves whose abundant foliage embowers the stream borders 

 at the altitude of about 4,000 to 5,000 feet. The tree's range 

 covers the coast plain and western slopes of m.ountains from 

 Alaska to southern California. The largest trees are on the 

 lowest levels. The dark rich green of the leaves gives this tree its 

 name. They are ovoid, 3 to 4 inches long, with the finest of saw- 

 toothed margins. The wood has come into extensive use for 

 the manufacture of various woodenwares and for staves of sugar 

 barrels. 



Swamp Cottonwood (Populus hderophylla, Linn.) — Round- 

 topped tree, 50 to 90 feet high. Bark red-brown, in narrow, 

 loose plates; twigs red or grey, containing orange pith. Wood 

 brown, light, compact. Buds resinous, ovate, with red scales. 

 Leaves broadly ovate, 4 to 7 inches long, serrate, dark green with 

 pale lining, when mature, covered with white tomentum as they 

 unfold; petioles round, slender; yellow or brown in autumn. 

 Flowers, March or April; staminate aments crowded, erect until 

 blossoms open; anthers deep red; pistillate aments few-flowered, 

 drooping. Fruit, May, aments 4 to 6 inches long; capsules few, 

 2 to 3-valved, ^ inch long, bell shaped. Preferred habitat, wet soil. 

 Distribution, swamps from southern Connecticut to Georgia and 

 Louisiana; north along Mississippi to Arkansas and Indiana. 



The swamp cottonwood is variable in the base, apex and 

 margin of its leaf. It may exhibit coarse or fine saw teeth, a 

 blunt or sharp-pointed apex, a square or heart-shaped base. 

 The conspicuous netted veins are always present, and the leaves 

 are always large and broadly ovate, with slim, round petioles. 

 The orange-coloured pith of the branchlets best distinguishes the 

 tree from other poplars. The new shoots and the unfolding 



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