One of our favorite tree care books, Landscaping with Native Trees, does a fantastic job of explaining how you can take common native trees and incorporate them into your landscaping. Not only do natural/native trees create visual interest, but it also makes it feel as if they perfectly belong in the environment. This book details out a list of native trees that you can add to your property that will also be disease and pest resistant, bringing you one step closer to becoming your own Denver tree services expert…
Apsen is a tree born of fires, landslides and other disasters. It colonizes disturbed areas and masses at the sunny edges of forests and meadows, where its white bark and gentle grace make it a favorite subject for nature photography. Aspens grow as clones – colonies of stems with a common root system. Fires and other disturbances periodically clear away the older stems, allowing ever more vigorous new sprouts to grow.
Quaking aspens are slender and graceful trees. Their white bark and delicate branching pattern might contribute to the illusion of small size, but aspens can become quite large on favorable terrain. The biggest single quaking aspen tree known was found in Ontonagon County, at the western end of Upper Michigan. It is 109 feet tall and over 3 feet wide. The closely related bigtooth aspen can grow even larger. One specimen in Marquette, Michigan is 132 feet tall and a venerable specimen in Caroline County, Maryland has. turns 4 feet 7 inches in diameter.
Quaking aspen derives both its common and scientific names from its foliage. The round leaves hang from flexible, flattened petioles and tremble with the slightest breeze. The scientific name actually means “like tremula”, a reference to the nearly identical European aspen, which I known for its similar shivering movement. The leaves are very finely toothed along their margins.
We have experimental provenance plot of aspen at Starhill Forest in Illinois; the trees have been propagated vegetatively from more than 30 locations across the entire natural range. The leaves vary in size, shape, fall color and phenology, spending on where the parent tree grows. Most turn bright gold in the fall, and some close from the Rocky Mountains include a little orange. Those from the East generally. have the largest leaves, up to 3 inches in diameter; those from central Alaska and the southern Rocky Mountains seem to have the smallest.
The Foliage of bigtooth aspen is similar, but it has course, irregular teeth along the margins. The two species are easy to tell apart in early spring because big-tooth aspen leafs out later, and its new foliage is covered with a white wool, as though cotton balls decorated the crown of the tree. The two species are more difficult to distinguish from a distance during the other seasons.
Flowers and Fruit
Aspens like all poplars, are dioecious, and each clone is either staminate or pistillate. In the high mountains, staminate clones seem to survive better than pistilate ones, but the genes are evenly mixed in most areas. The flowers are small catkins similar to those of willows and they are not particularly conspicuous. Those of the bigtooth aspen open later than those of the quaking aspen.
Female trees release great quantities of seed in early summer every few years, but the tiny seeds are so perishable that few remain viable long enough to sprout. This doe snot pose a challenge to the tree’s survival because almost endless generations of clones may grow from a few seeds that do not take root.
- Fall- the golden foliage, backlit and shivering on white stems along stands of dark evergreens is perhaps the most popular of all nature photographs for calendars.
- Early Spring – As the misty lime green new leaves of quaking aspen and the white leaves of bigtooth aspen expand.
- Summer – when the foliage dances in the wind
Native and Adaptive Range
If you live anywhere in the cooler portions of North America, quaking aspen trees are probably near. Aspen ranges from northern Alaska to the mountains of Central Mexico, eastward across every portion of Canada that has a growing season long enough to support tree growth, south through the moist, cool highlands of Virginia and Missouri and throughout the the mountains of the West. Our testing indicates that trees of western mountain origin are not as vigorous in the Midwest as those from local and more eastern sources. Root cuttings or small sprouts should be gathered locally when you are planting near the limits of species natural range. Locally adapted provenances of quaking aspen are hardy north into USDA zone 3.
How Can We Serve You?
Wondering how to identify if a tree on your property is a Quaking Aspen? Ask one of our family tree service specialists in Arvada, Lakewood, Wheat Ridge, or Aurora! Contact our Denver tree trimming experts for a free estimate. We look forward to meeting with you and sharing our passion for tree removal and care!