QUAKING ASP; ASPEX (Populus tremuloides, Michx.). 40 

 to 80 and 100 feet. Slender, round-topped tree, with stout, 

 angular branches, and slender twigs set with small, waxy buds. 

 Bark rough, dark, with flat ridges and deep furrows, becoming 

 paler on limbs, which are subtended by broad, black, rough 

 scars; small branches pale gray, or white, with warty excres- 

 cences. Wood light brown, soft, weak, not heavy nor durable, 

 used for fuel. Leaves l to 2 inches long, ovate or almost 

 circular, with straight base and pointed apex; margin evenly 

 saw- toothed; surface smooth, dark green, shining, pale yellow- 

 green beneath; petiole slender, flattened. Flowers dioecious, 

 March; catkins 2 to 3 inches long, each flower on a lobed and 

 silky fringed scale. Fruit in May; capsules oblong. Dist.: 

 Sandy, dry soil, Newfoundland to Alaska, south to New Jersey, 

 Kentucky, and Nebraska; on high altitudes following the 

 Rocky Mountains and coast ranges almost throughout. Es- 

 pecially valuable cover of forest land swept by fire, serving 

 as nurse tree to conifers and hardwoods. 



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