336 NEW ENGLAND TREES IN WINTER. 



93. Leaves bluish green, %-% inch long, cones ovate, %-!% inches 

 long, persistent on tree for more than a year; a tree growing 

 chiefly in swamps or lowlands, generally under 30 ft. in height, 



sometimes fruiting when less than 5 ft. high 



Black Spruce (Picea marianaj p.302 



94. Leaves green, cones 4-7 inches long, cultivated species 



Norway Spruce (Picea Abies} p.306 



94. Leaves bluish green or silvery 95 



95. Cones 2^-4 inches long, cone scales distinctly longer than broad 



with narrowed, ragged, blunt apex; cultivated western species 



Blue Spruce (Picea Menziesii) p.3(>4 



95. Cones l%-2 inches long, cone scales rounded, not ragged; leaves 

 generally with unpleasant odor, native in northern New England" 

 but cultivated further south. White Spruce (Picea canadensis) p.358 



THE POPLARS 



Populus. 



Rapidly growing trees generally with erect more or less continuous 

 trunk forming generally distinct whorls of branches at top of each 

 year's growth by which the age of the tree may be estimated; branchlets 

 brittle easily separating at point of attachment; young bark smooth, 

 generally light colored; pith, F-pointed star-shaped, upon drying 

 generally turning brown or black; leaf-scars large, 3-lobed, inverted 

 triangular, covered with a light colored corky layer; stipule-scars 

 generally distinct, narrow; bundle-scars 3, simple or compound in 3 

 groups; buds with the first scale anterior (facing outward), the first 

 pair of scales small and opposite; scale-scars marking annual 

 growth persisting for several years; seeds downy, produced from catkins 

 in spring, the tree often spreading widely by formation of root 

 suckers. The Poplars resemble the Willows but are easily distinguished 

 by the numerous scales to the bud. In addition to the native species 

 here described a rare form, the Downy Poplar. [Populus heterophylla L.] 

 occurs locally in swamps in southern New England. 



96. Twigs of past season more or less slender, covered at least at apex 

 V.'ith white cottony felt which may be readily rubbed off exposing 



the Kreenlrh bark below Silver Poplar (Populus Zba;p.3S 



$6. Twigs smooth, n^t at all covered with white felt 97 



37. Twigs yellowish 98 



37. Twigs not yellowish (generally reddish-brown) 9 



98. Lateral buds for the most part divergent, large, about 10 mm. or 

 more in length, tree with more or less pyramidal head, but not 

 narrowly spire-shaped Carolina Poplar (Populus deltoides)v-3$4 



98. Lateral buds for the most part appressed, smaller, generally under 

 8 mm. long, tree narrowly spire-shaped 



Lombardy Poplar (Populus nigra, var. 



99. Buds more or less pale dusty-downy 



Large-toothed Aspen (Populus grandidentata) p.3J)O 



99. Buds not downy 100 



100. Buds large, over 15 mm. long, covered with fragrant sticky gum. 



BalHitm Poplar (Populus balsamifera)i?.!W2 



100. Buds small, under 10 mm. long, shiny, slightly sticky but not 



fragrant Small-toothed Aspen (Populus tremuloidcs)j?.388 



THE HICKORIES 

 Carya. 



Trees with smooth gray tough bark in young trees, becoming rough- 

 ened with age; twigs in the main stout, tough, flexible, but with 

 difficulty broken, dark, sharply outlined against the sky; buds more or 

 less naked to evidently scaly, frequently superposed, the lateral some- 

 times enclosed in a sac soon splitting at the top and often stalked; 

 leaf-scars alternate, more than 2-ranked, large, conspicuous, more or 

 less 3-lobed inversely triangular; bundle-scars conspicuous, more than 3, 

 irregularly scattered or collected in 3 more or less regular groups, rarely 

 in a straight line; pith not chambered except at nodes, sometimes some- 

 what star-shaped in cross section; lenticels oblong, conspicuous; fruit 

 an unsculptured nut, inclosed in a husk which splits into four valves 

 at least at the apex. 



