Now that the air has a crisp autumn tang, I will be spending some time with a chainsaw in the woods around my house. Cutting firewood is a good excuse to spend time outdoors, and given a year so dry, this year’s work becomes next year’s toasty toes. Cutting firewood does more than fuel my wood stove, though. When done right, timber harvests can enhance forest health and wildlife habitat. Firing up my Poulan is ecological activism.
Simply because Missouri’s forests turn green every spring, most people never realize that much of the state’s forestland is not very healthy. That is because our forests have been harvested multiple times since pioneer days. Those harvests seldom were done with long-term forest health in mind. As a result, much of our forestland today is not as productive as it could be.
The most common problem is overcrowding. Trees growing too close together don’t get enough sunlight, water or nutrients. Eventually, this leads to straggly, bent, knotty trees that produce few acorns, nuts or other other natural fruits that deer, turkeys, squirrels, songbirds and other wildlife depend on for food. Judicious removal of excess trees relieves crowding, improves the health and productivity of remaining trees and makes forests more beneficial for wildlife.
What does “judicious” mean? For one thing, it means selectively removing the least healthy and least desirable trees. If you have a stunted old hackberry tree growing next to a straight young red oak, it usually makes sense to cut down the hackberry and use it for firewood.
You don’t want to remove all the unhealthy trees. Hollow trees and standing dead trees – known as snags – are extremely valuable as nesting, feeding and denning sites for wildlife from woodpeckers and raccoons to flying squirrels and tree frogs. You should leave one 18-inch or larger living, hollow tree per acre. You also want to keep at least two snags and two live, hollow trees 10 to 18 inches in diameter and one snag and one live cavity tree 6 to 10 inches in diameter on every acre. Oaks, hickories, black gum and sycamore trees generally are the best choices for hollow trees and snags.
How crowded is too crowded? Foresters have a rule of thumb for this. They start with a tree they want to keep and check its diameter in inches. Then they double that number and leave about that many feet between the chosen tree and the nearest trees of similar size. For example, after thinning, a 16-inch tree should be at least 32 feet from the next big tree.
This is only a rule of thumb, not a law. Be flexible in applying it. Let’s say you have two healthy 12-inch oaks growing only 12 feet apart. Around them are dozens of smaller, less desirable and less vigorous trees. In this case, you should leave the two big oaks and cut down less desirable, similar-sized trees at more than the usual distance around them. This saves two high-value trees while giving each enough space to thrive.
Don’t cut down all the trees around those you choose to leave. Remember that when your chosen trees get old and either die or are harvested, you will need young trees to replace them. If you have a 30-inch giant, leave some young trees within the prescribed 60-foot radius, but keep them well spaced, according the rule of thumb outlined above.
Some people won’t consider cutting trees on their land. They think they are “saving” trees and keeping their forests pristine. That is an illusion. Forests are dynamic systems, changing over time even without human intervention. Because our forests have been badly managed or even abused in the past, refusing to manage them with selective cutting usually only perpetuates bad situations.
Most forests need more trees removed than the average person can burn for firewood. Some people sell the excess firewood. I use medium-sized limbs to build brush piles, further enhancing the benefits that timber-stand improvement harvests provide for wildlife.
If you have cedar trees in your woods, consider some of the uses I listed in my Aug. 26 post, “Enduring Red Cedar.”
Don’t feel guilty about cutting firewood. It’s a renewable energy source, part of our energy-indepencence solution, and it can provide multiple ecological benefits if you do it right.