Following a day of wind gusts reaching 60 miles per hour around Howard County, the Tree Pros crew gathered to remove a fallen oak in Ellicott City. Dealing with storm falls is always a little sad for us, but particularly in this case because the tree had been perfectly healthy before its roots were torn up from the ground. Magnificent in fact, a big tree, with a high crown of leaves and long widely branching limbs spread out around it.
We can detect disease, unsoundness, and planting conditions that make a tree a storm risk. Failures like this one where the tree was healthy and its location unremarkable are harder to predict. We can’t say we could have done anything that would have saved this oak. However, if we had seen it before its fall we would have recommended thinning. Perhaps, just perhaps, thinning would have made a difference.
What Is Thinning?
The thinning of a tree involves selective removal of branches from a tree’s canopy, improving structural soundness and the flow of air and light. Thinning can be conducted in pursuit of goals such as–
- Wind storm preparedness. As appears to have happened with our Ellicott City oak, dense clumps of foliage can trap the wind. The tree canopy becomes like a sail, yanking the roots in the direction of the wind. Proper thinning lets the wind pass through.
- Snow storm preparedness. More branches offer more places for snow to accumulate, the snow’s weight breaking limbs and in extreme circumstances the whole tree. Proper thinning alleviates this problem.
- Land improvement. Too much shade prevents plants from growing and can limit your enjoyment of your property. Proper thinning lets more sunlight through.
- Reduction of fungal disease and pests. The air and light provided by proper thinning support tree health.
- Improved tree appearance. Typically, proper thinning is subtle. You won’t see a dramatic change in tree shape or size as with some other types of pruning. However, the discerning eye may note less shagginess, more of an elegant lacy look.
Doing Thinning Right
We always start with and focus on “structural” thinning, thinning that will improve the tree’s structure and strengths. We remove dead wood and defective branches along with those that threaten to compromise internal balance (overly long, codominant, and so on).
You might think that we would prune a good deal in the middle of the canopy, where it is thickest. In fact good thinning concentrates on the small branches toward the outside of the canopy. Trimming too much in the middle, creating the dreaded “lion tail” shape, weakens the tree rather than strengthening it.
Proper thinning removes perhaps only 5 to 10 percent of the foliage in the case of a mature tree. For a young tree around 25 percent should be the maximum. The key is knowing what to remove to benefit true, long-term tree health and survival.
Tree Pros is happy to look at your trees, healthy or sick. Just request a free visit and estimate.