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Aspen Regeneration Cut

Posted: February 13, 2015

One landowner's experience with regeneration cuts to revitalize stands of mature aspen.
View of the cut August 22 2013.  Many sprouts are over 7 feet tall. Photo by Paul Demmert

View of the cut August 22 2013. Many sprouts are over 7 feet tall. Photo by Paul Demmert

Our sixty acre property is about fifty acres of wooded area and ten acres of meadow. Most of the forest is a combination of mixed hardwoods (red and white oak, red and sugar maple, hickory) with some evergreens (white pine, pitch pine). Near our home we have two very small (less than 0.5 acre) groves of aspen, both quaking (Populus tremuloides) and bigtooth (Populus grandidentata) species, although the bigtooth clearly dominate both groves. We had noticed that several mature aspens in both groves were dying, so we decided to attempt regeneration cuts.

For aspen, the typical approach to regeneration is to remove all the trees in a single harvest. Clearcutting aspen stimulates root sprouting and minimizes shade on the site. Clearcutting helps to raise soil temperatures above fifty-five degrees, and stimulates root sprout initiation. We were aware that cutting the trees should be done in the winter to avoid disturbing the soil and aspen root network. We decided to leave some trees for bird roosting; a clearcut with some retention.

Our overall goal was to revitalize the aspen groves and provide better habitat and food for ruffed grouse. We later found that a regenerated aspen stand also benefits deer, rabbit, red squirrel, purple finch, yellow-bellied sapsucker, red-breasted nuthatch, yellow warbler, warbling vireo, and northern flicker. Some of these species feed on aspen catkins and seeds, some eat twigs and tender leaves and buds, while others use the aspens to nest and to hunt insects.

In mid-March 2012, my wife and I cut the smaller (less than 0.25 acre) aspen grove using a chainsaw, felling about forty trees with the average diameter of ten to twelve inches. This grove held a number of oak and white pine trees; we left those trees untouched. Regeneration following cutting is rather sparse, probably because the trees left in the grove shaded the soil and did not stimulate aspen root sprouts. After two growing seasons, most of the aspen root sprouts are on the periphery of the original grove.

Aspens in the second grove (about 0.5 acre) were larger, twelve to eighteen inches in diameter, and close to sixty feet tall. There were several tall oaks in this grove, mostly on the periphery. The aspen trees were densely spaced. We knew we would have problems felling the trees because of the potential of creating “leaners” when the tree we cut got hung up on standing trees. We had that happen several times in the first regeneration cut, and this grove had a significantly higher density of aspen trees and they were larger.

We got some help from the U.S. Fish and Wildlife Service’s, Partners for Fish and Wildlife Program. They had access to a skid steer with a shear cutter that could hold the tree after cutting, and then carry the tree away from the stump. Once again the cutting took place in mid-March 2013. They did a great job with the skid steer and shearing machine. After cutting the trees they used the skid steer’s grappling arm to move the fallen trees around into different piles, opening up more clear space for the coming anticipated aspen root sprouts. They used a chainsaw to buck the larger aspen logs to move them more easily. They left a couple of oaks and a few smaller wild cherry trees standing, and, when finished, there was a lot of open space where the sun could warm the ground above the existing aspen root complex.

This second cut occurred while the ground was still frozen; soil disturbance was minimized and the skid steer caused limited surface disruption. The last frost of the season occurred on May 13 and in the following week on several days temperatures were above eighty-five degrees. Root sprouting began in late May. By late-June the sprouts were numerous and three feet tall. By late July the sprouts were up to five feet tall. By late August the sprouts were topping seven feet. In areas clear of slash and open to direct sunlight, sprout density is very high. In those areas where the sunlight is more diffuse or the slash is denser, the sprout numbers are as expected much lower. As the grove matures, sprout density will decrease as the competition increases and they compete for light.

The harvesting techniques and machinery, avoiding soil disturbance, moving slash into piles to open more clear space within the grove, and completing the harvest before the ground thawed all contributed to successful root sprouting. We think the second aspen regeneration cut has been very successful, and we will monitor the new aspen stand for future effects on wildlife.

Contact Information

Paul Demmert
  • PA Forest Steward Volunteer