Nature Bulletin No. 325-A   December 14, 1968
Forest Preserve District of Cook County
Richard B. Ogilvie, President
Roland F. Eisenbeis, Supt. of Conservation

****:THE QUAKING ASPEN

Trees have voices. The soft whispering rustle of a Quaking Aspen is 
much different from the sound of a cottonwood or any other tree. They 
have personalities too, and the leaves of each kind move in a distinctive 
manner. The Quaking Aspen is America' s liveliest tree . In the slightest 
breeze, its small round leaves tremble almost incessantly, like thousands 
of butterfly wings, fluttering and twinkling all over it. You will find out 
why if you watch the pixy dance of just one leaf: the stem, from one and 
one-half to three inches long, is flat, flabby, and turned at right angles 
with the blade of the leaf.

Quaking Aspen, also called Smalltooth or Trembling Aspen, and 
"popple" by lumbermen, has two other distinctions: it grows on a 
greater variety of sites than any other species of tree in North America 
and has by far the most widespread range. The Bigtooth .Aspen, also 
called "popple", is commonly found with it but occurs only in the 
northeastern quarter of the United States and in adjacent Canada. 
Quaking Aspen thrives on sandy soil, in wet ground and tamarack 
swamps, in high dry places, and from sea level to elevations above 10, 
000 feet. It is common in northern Illinois, all of our Great Lakes and 
northeastern states, and most of Canada. It also extends from Labrador 
and the shores of Hudson Bay to the Yukon Valley in Alaska; south 
through the Rockies and Sierras into Lower California, Mexico and 
New Mexico; south along the Appalachians into Kentucky; and is 
scattered through the northern Great Plains states.

In the cut-over and burned-over forest lands of such states as Michigan, 
Wisconsin and Minnesota, this tree and the Largetooth Aspen make up 
the principal forest cover on millions of acres. They protect and 
improve the soil. They provide shade for the maple, pine, balsam and 
other species that gradually replace them because aspen do not like 
shade. It is a tree of sunlit openings. Popple thickets furnish excellent 
cover and food for game. The buds are important winter food for ruffed 
grouse; elk, deer and snowshoe hares chew the bark and twigs; moose 
and porcupines eat the twigs and foliage; beaver prefer aspen for their 
dams and lodges, and the inner bark, although bitter as quinine, is their 
favorite food.

Aspen frequently reaches 40 feet in height and diameters from 12 to 18 
inches. In the southern Rockies, however, it may become 100 feet tall 
and three feet in diameter. In autumn the pale green foliage turns golden 
yellow, especially brilliant in those western mountains where the aspen 
provides most of their fall color. Eighty years is old for an aspen 
because, being very susceptible to fungous diseases, borers, tent 
caterpillars and heart rot, many are killed before they are 50. They are 
easily killed by fire but sprout vigorously from the stumps.

The trunks and branches of an aspen, except at the nearly black, 
roughened base of old trees, is smooth and chalky white tinged with 
green, marked with darker horizontal scars. The male and female 
flowers appear on separate trees as drooping gray catkins in early 
spring. The fruit is a string of light green capsules, each shaped like a 
little Indian club and packed with tiny brown seeds. Each seed has a 
little tuft of white hair and may be blown long distances but it is short-
lived and will not sprout unless it soon lodges in a favorable place.

For generations, aspen was considered worthless. Now it is cut for pulp 
to make the best grades of paper for books and magazines. Its soft white 
weak wood is also used for matches, boxes, crates and, especially, 
excelsior. In the west it is used for cabins, fences and many other 
purposes.

"Tho heart of oak be e'er so stout, keep me dry and I'll see him out".