QUAKING ASP; ASPEN (Poplins 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 14 to 21 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 dicecious,
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.