Look for trapped debris in branches

High winds in the fall and winter storms sometimes trap debris in the branches of trees. Examples could be oak limbs stuck in a nearby crabapple or tulip tree stems stuck in a neighboring lilac. Depending upon height, the debris may require a long-handled implement like the extendable tree pruner. A 12-foot long pruner is great for cutting branches no bigger than 1¼” diameter. I like to use it to extract dead branches I couldn’t normally reach. The pruner also includes a saw blade for cutting through thicker branches while you stand safely on the ground.

How to spot insects and disease damage

Rex Bastian, International Society of Arboriculture Board Certified Master Arborist® with Davey Tree, suggests that insects and diseases sometimes leave indicators of their presence that can be spotted during the dormant season. “Diseases that affect the wood, such as cankers, can be identified because they distort or cause lesions in the wood. Some conifer diseases, such as tip blights or needlecasts, can discolor needles and shoots to the point where they are obvious.”

Look closely at the bark on deciduous trees, where you may find evidence of insects. An example is a borer which leaves tell-tale holes in the bark or stem. The holes result from either beetle or moth larvae that tunnel through the plant. The holes may indicate an old infestation, but plants with such signs should be watched during their growing season for dead branches or premature leaf drop.

Bark Beetle Emergence Holes  (photo by Davy Tree Expert Co.)

“Overwintering scale insects can be observed on twigs or foliage,” Bastian advises. “Some sapsucking insects, like the boxwood psyllid, distort foliage that persists into the winter, giving notice of their presence.”

The boxwood psyllid is already gone when you see signs of its damage in mid-winter. Make yourself a reminder to trim back the damaged stems in early spring, ideally when the threat of sub-zero weather has passed, say early-to-mid March. Throughout the summer, keep an eye on the boxwood for repeated infestation.

Prune to correct planting mistakes

Who hasn’t planted a tree or shrub that’s outgrown its space? I planted a weeping katsura (Cercidiphyllum japonicum) ‘Pendulum’ too close to my driveway several years ago, and asked Bastian, the master arborist, for his recommendations. He advised: “Trees that begin to overgrow their allotted space can be safely reduced in size as long as the process is started before it gets out of hand.  The important thing not to do is simply chop it back to where you want it.  Growth can be directed by skillful pruning, but it needs to be done by someone who knows what they are doing. Repeat pruning will likely be required every few years to keep the tree in bounds.”

Weeping katsura planted too close to driveway (photo by Jean Starr)

I had been shaping the Katsura tree for the past several years. But I missed a few years and its branches now are lightly feathering my car each time I pull into the garage. I will have to deal with those thin, flexible branches before they become strong, thick branches and rip my side mirror off.