98 



DOWNY POPLAR. 

 Populus heterophylla, Linnaeus. 



FORM — In the north usually a small tree from 30-50 ft. high; in the south may reach a height 

 of 100 ft. with a diameter of 3 ft. Crown high, rather broad and round-topped. Trunk short, con- 

 tinuous, and tapering. 



BARK — On old trunks thick, light reddish-brown, rough, broken by long fissures into long 

 narrow plates. Cn younger tiunks and large branches thinner, not so rough; fissures shallower 

 and ridges smoother than on old trunks. 



TWIGS — Stout, light yellowish, marked by a few scattered pale lenticels, roughened 

 elevated leaf-scars; pith orange-colored. 



BUDS — Alternate, broadly ovate, slightly resinous, bright reddish-brown, covered with 4 

 scales which art slightly pubescent towards the base. Leaf-buds about J of an inch long 

 Flower-buds about i of an inch long. 



LEAVES — Alternate, simple, broadly ovate, cordate, rounded or truncate at base, rounded 

 or acute at apex, coarsely serrate on margin, 4-7 inches long, dark green above, pale gr^en 

 below: leaf -stalks round. 



LEAF-SCARS— Alternate, large, elevated, often 3-lobed, indented on upper margin; with 

 3 conspicuous bundle-scars. 



FLOWERS — Appear in March or April. In general similar to the Cottonwood only both 

 staminate and pistillate aments are shorter. 



FRUIT — A drooping ament, when mature about 4-6 inches long, bearing a few, scattered 

 dark green, 3-4-valved capsules containing small seeds surrounded by a mat of white hairs. 



WOOD — Same as that of the Cottonwood only slightly heavier. See description page. 99. 



DISTINGUISHING CHARACTERISTICS— The Downy Poplar, also known as Swamp Cotton 

 wood, Black Cottonwood, River Cottonwood, and Swamp Poplar, may be distinguished from 

 all the Aspens, Poplars, and Cottonwoods native to this State by its round leaf-stalks. The 

 leaf-stalks of all the others are laterally flattened. The leaves are large and more bluntly 

 pointed than these of the other species. The leaf-margins are not so finely toothed as those 

 of the American Aspen but finer than the other two native species. The bark on old trunks 

 light reddish -brown . The twigs are stouter than those of the Aspens and contain orange 

 colored pith. The Aspens have white pith. The buds are bright reddish-brown, slightly resinous 

 covered with scales which are often pubescent near the base. 



RANGE — Connecticut along coast to Georgia, west to Louisiana, and northward to Kentucky 

 and Missouri. Its range suggests a somewhat contorted horseshoe. 



DISTRIBUTION IN PENNSYLVANIA — Found only in the extreme southeastern and southern 

 parts of the State. Reported from Chester, Delaware, and Franklin counties. Very rare and 

 local. 



HABITAT — Found only in low wet situations, and always mixed with other species in this 

 State. 



IMPORTANCE OF THE SPECIES — This species is too rare and local to be of any commerc 

 importance. It is not attractive ornamentally on account of its heavy limbs and sparse 

 rounded crown. The wood is not listed separately on the market but bought and sold 

 as Cottonwood. 



