Big-toothed aspen (Populus grandidentata)
Medium to large; height sometimes 60' to 80', diameter 10" to 20"; slender, rather rigid branches create narrow round-topped crown.
Smooth, gray or yellowish green; furrowed and dark brown at base of old trees.
Simple, alternate on stem, length 2" to 4"; coarse toothed; dark green upper surface turning yellow in autumn; appears one to two weeks later than that of quaking aspen, and at first is silvery white. Buds are light gray, downy, and larger than those of quaking aspen.
Capsules are grouped in 3" to 6" long catkins; matures in late spring.
Found on sandy or rich soils that are moist; common, except in the southwestern and northeastern parts of Minnesota; shade intolerant, very fast growing.