In a season of ice and snow, winter weather can cause stress to trees that landscape homes. But there are steps homeowners can take to insure the health and beauty of their trees.
“There are things you can do for trees planted in the yard,’’ said Russ Gibbs, service forester for the Pennsylvania Dept. of Natural Resources for Fayette, Greene and Washington Counties.
One protection is to spread mulch around the trees.
“Mulch generally retains soil moisture and increases winter soil temperature and improves the soil structure — the nutrient levels,’’ said Gibbs.
But Gibbs said never volcano or mound the mulch against the tree.
“That produces heat and promotes growth of secondary roots that can circle a tree and choke off the main roots,’’ Gibbs said. “In some trees, it can prevent the natural hardening of the bark, which is the trees’ self-defense mechanism.’’
Gibbs advises placing a two-inch layer of mulch where the canopy stops on the outside perimeter of the tree.
“A lot of times, especially in commercial lawns, you see volcano mulching. It’s aesthetically pleasing but it results in a decline of the trees. It’s a slow decline and you don’t associate it with mulching,’’ said Gibbs. “It does look nice, but it’s not good.’’
Braun said you can add mulch anytime of the year but said if you wait until the ground freezes, it prevents moles and mice from nesting.
“But we’ve had freezes and then 50-degree weather so it’s tough to predict,’’ said Gibbs.
Clyde Braun Jr. of Markleysburg, consulting forester for the Department of Agriculture’s Natural Resources Conservation Service, observed winter’s freezes and thaws can also damage trees.
“The ground gets soft and the tree starts to lean because of ice loading. If the ground is soft, it’ll pull the roots out. You’ve seen it on TV with hurricanes but the same thing can happen in winter,’’ said Braun. “If it starts to lean over a house, a path or where you park your cars, be aware and take the tree down. Try to minimize damage, especially in target areas where people or valuable property exists, like a house or shed.’’
Braun explained that ice loading is when there’s a heavy weight on the trees.
“Freezing rain hits the trees. It’s beautiful and sparkles in the sunshine but it loads the tree roof,’’ Braun said. “I had a tree with a six-inch trunk. It was weighted with freezing rain and it bent the top of the tree to the ground. I took the ice off and it came back up but it still leans.’’
Gibbs said ice loading can also snap limbs off a tree.
“Sometimes I’ll go out and shake the snow off a tree if it’s a heavy, wet snow,’’ remarked Gibbs. “It’s not a common practice, just something you can do if you have the time.’’
Rock salt can also cause problems for trees.
“It prevents moisture retention in the roots,’’ explained Gibbs.
Braun noted some people plant evergreens near roadways, where the trees might be affected by salt spread by highway departments.
Both men noted some species of trees do tolerate salt.
“DCNR has a list of trees that are salt tolerant on its website,’’ said Gibbs.
When visiting the site, www.dcnr.pa.gov, do a search for backyard trees to find links to information for homeowners.
Winter is also a good time to prune your trees.
“The best time is fall and winter. You don’t have insects transmitting disease. You can prune your tree and it starts to heal over,’’ said Braun. “And you don’t have sap running out and attracting insects. They carry disease — not intentionally — but they carry disease like oak wilt. This is spread by insects attracted to a freshly trimmed stub, which is where the branch meets the trunk.’’
Gibbs said, “When you prune in the winter, the tree is dormant and it heals. It forms a callus. In the spring, it doesn’t heal because of the sap flow in the growing season. It’ll promote growth.’’
If you know proper techniques, you can prune the tree yourself. If not, Braun and Gibbs noted Penn State Extension has online classes as well as workshops that you can attend. Gibbs noted the DCNR website also has pruning practices.
“I would recommend consulting the guide because there are a few pruning cuts that can be detrimental,’’ said Gibbs.
But if you’re not familiar with proper techniques or don’t have time to learn, hire someone with experience.
And Gibbs observed, “On more mature trees, I would definitely hire a professional.’’
Both men recommended using one certified by the International Society of Arborists.
“It’s going to cost you more than a guy who has no certification but if it’s a valuable tree — you grandfather planted that tree — then you want to get an arborist to look at it and arrange for pruning,’’ said Braun. “It depends on how much you’re willing to spend to keep that tree.’’
Both men also noted an arborist can do a risk assessment on the tree.
“An arborist can inspect for things the average homeowner can’t see, like gypsy moth damage,’’ said Gibbs.
In addition, Gibbs recommends homeowners use tree protection for new plantings to avoid damage from deer.
“Deer can do a heck of a lot of damage to a tree. You can prevent them from rubbing the bark off and browsing the canopy,’’ said Gibbs. “They are looking for food in the winter. Deer, on average, can eat five pounds of browse a day.’’
Gibbs recommends tree tubes, which can be purchased online, at different heights, such as 3 feet and 5 feet.
“Tree tubes only work on hardwood seedlings where conifers — pine trees — you would use fencing,’’ said Gibbs. “Conifers need full sunlight.’’
Fencing should be set about 3 feet from the trunk of the tree.
Gibbs said, “It will vary, depending on the species and the form of the tree.’’
Finally, keep an eye on your tree throughout the winter.
“The main thing for taking care of your trees is monitoring,’’ said Gibbs. “It will give you an idea of what you can do for them.’’