Though trees will go dormant soon, their owners will not.

“The best time for pruning trees is late, late in the dormant season,” said Mike Nelson, forester for the state Bureau of Forestry district that covers Butler County. “Generally mid-November and then until spring is the best time.”

During the dormant season, “If you would happen to skin something on another part of the tree or cause other damage, it wouldn’t hurt the tree as much,” he said.

Nelson is a district forester for the Kittanning State Forest. Moraine State Park is not a part of that area, but the forestry bureau has an office in the Region 2 park office. Nelson, of Indiana, Pa., has been performing this job for a year and a half.

Five foresters are in charge of 3,000 acres, mostly managing timber sales, recreation and hiking trails, he said.

On that land are deciduous trees, those that lose their leaves annually, and conifers, mostly known as evergreens.

“There are some apple trees out there for wildlife; we prune those, but we’re mainly looking for large-scale insects or disease,” he said.In his job, he works mostly with private landowners, large or small, anywhere from two acres and up, to manage their wooded areas, he said.“They usually want to improve their woodlot for timber production or for wildlife purposes,” he said.To increase the number of deer or turkeys in an area, Nelson recommended planting oak trees. Evidently, both animals really like the acorns.“A lot of people know that something needs to be done — but they don’t know what — just to maintain it, to repair it.”This year, Nelson said he is starting to take calls from residents with a timely problem.“Right now I’m getting a lot of calls about cutting firewood because the price of oil is going up. A lot of it is just ‘What trees should I cut?’”For timber production purposes, keep the more valuable trees, like the black cherry, and cut out less valuable trees, like the red maple, Nelson said.“Red maple is considered a competitive species. It’s fairly fast growing. If the red maple and black cherry are growing together, the red maple is going to crowd out the black cherry. Even so, the black cherry around here is not as good as, say, in the Allegheny National Forest (in north central Pennsylvania).”Still, clear cutting is not advisable.“You don’t want to cut it all; you want diversity,” Nelson said.Fruit trees are pruned differently than trees destined for timber sales, said Dennis Waldorf of the Woodland Owners of Clarion-Allegheny Valley. The group hosted a workshop on pruning recently.

“Basically the rule for mostly all fruit trees is you want to cut any limb growing vertically. You want to keep it kind of sparse,” Waldorf said.“The more energy the tree uses growing, the less energy the tree can use growing fruit.”If a tree is being grown for timber, a straight trunk with the fewest branches is desirable, Waldorf said.“You have to leave enough leaf structure so it lives. Leave at least a third of the branches up high,” he said.Trees in an individual homeowner’s yard are pruned for different reasons, though the Woodland Owners group cites a statistic that 90,000 families in Pennsylvania own five or more acres of wooded area.The first reason homeowners might prune trees would be for “aesthetics,” cutting off the lower branches to be able to get a lawn mower underneath, for example, Nelson said.Pruning also should be done for the health of the tree.“You want to cut out any dead parts, diseased parts or malformed parts of trees,” he said.Look for disease on the trunk or branches where cankers may be visible. These are sores that may be oozing sap, Nelson said.“Cankers can look like targets, adding a ring year after year. Eventually, it will girdle the tree, pretty much choking the tree. The leaves look green but it’s stressed.”Some diseases attack the roots, like root rot, a fungus — and that can’t be seen, Nelson said. But woodlot owners can watch for signs in the tree.One sign is crown die back, when leaves curl up, turn brown and thin out in the crown of the tree.

“You’ll have crown die back; that’s the first sign, but as soon as you see that, the tree is pretty much done for. You’d want to get it down as soon as possible, especially if it’s close to the house.”If a tree is diseased, often there’s nothing that can be done to reverse the situation, Nelson said.“Just try to keep the tree as healthy as possible,” he said. “If there’s a drought, water it. For landscape trees, it’s good to put mulch around the base. That will keep the mower away from the trunk, and possibly running into it, and will help keep water in.”Some signs might look suspicious but are harmless. For instance, a blue, lacey scale that grows on a tree’s trunk is just lichen, Nelson said. It’s not bad for trees.A tree might also be pruned for structural issues. A V-shaped, split-growth trunk is weaker than a U-shaped arrangement, and one side of the V should be removed, he said.Starting small, a hand pruner is easiest for thin branches. Moving up the line of equipment, loppers are good for branches up to 3 or 4 inches around, Nelson said.“If you have to open the lopper the whole way to fit the branch in, you don’t want to do that. That branch is too big.”Then it’s time to move on to a hand saw, the ones with teeth. Pole pruners are good for distances out of reach.A chain saw can be used for pruning large branches that can’t be removed with a lopper or handsaw.“The chain saws we use are for clearing roads in state forests, if trees fall down, and for maintaining hiking trails. We also have a campground we cut firewood for,” Nelson noted.“The best advice about pruning is to have your tools sharp, as sharp as you can get them,” he said. “You want a nice, clean cut.”The cut will be made close to the joint, but not exactly flush.“You have to come out a little, past the knuckle or collar,” Nelson indicated.Do not cut off the collar; it helps the tree heal.“You probably will want to cut off some of the branch out farther first, because the weight could pull down on the part close to the tree and break off, causing damage,” he said.Cutting off branches is fine, but don’t “top” trees, Nelson advised.“(Topping) stresses the tree a lot. It will hang in there, but eventually, it will die.“The best thing to do is just take it out and plant a tree that won’t grow to get in the way, but that is hard to do. Some trees are said to grow 30 to 40 feet but then they grow higher.”Although they don’t prune themselves, some trees are known as self-pruning.

White pines, red pines, most of the pines do it, Nelson said. Self-pruning means the lower branches die back and can just be trimmed off.Another sign not worrisome in an evergreen is a scattered yellowing of needles. Nelson called it “needle cast.”“I get a lot of calls about that beginning right around this time of year,” Nelson said.Those yellow needles will eventually turn brown and fall off, and no, it doesn’t mean anything is wrong with the tree.“It’s like it’s shedding its skin,” Nelson said.There aren’t really any trees that are disease-free, so woodlot or homeowners should pick what they like.Sugar maples have nice, symmetrical form to them, but a lot of people like different shapes, Nelson noted.Oaks are always good, long-lived and nicely shaped, but not if you don’t want all the acorns around, he said.One word to the wise comes from Gene Whited of Sarver, a member of the Woodland Owners.Sugar maples are the one tree that shouldn’t be pruned into March,” he said, “unless you’re planning to make syrup!”