How to replace trees downed by winter storms
Wednesday, February 16, 2011; 10:58 AM
Recent storms have toppled trees or splintered branches, and left disfigured and compromised survivors. Some readers have asked for suggestions for replacements, with an emphasis on finding, in the words of one, "reasonably mature trees."
Forgive me if I harp on this, but the message hasn't gotten out. A small tree with a trunk an inch across is far cheaper, more manageable and, moreover, happier than a three- or four-inch tree that looks "reasonably mature."
The smaller tree will establish itself more quickly and within a few short years will catch up to the bigger tree in size. The root system will be better developed.
My favorite e-mail came from Lisa McAllister of Silver Spring, who wisely observed: "I just wonder if most of the damaged trees we are seeing post-storm weren't already compromised in some way."
The answer, of course, is yes, and a tree's fate may be sealed the day you plant it. Apart from planting something after its pliable infancy, there are so many pitfalls: planting in thin or wet soils, planting too deeply, planting in too much sun or too much shade (depending on the species) and planting in beds that are too small - all these shortcomings will come back to haunt you.
Casey Trees, the nonprofit group seeking to restore the tree canopy in the District, says a tree needs at least 1,000 cubic feet of soil volume to develop fully. That would be a bed 10 feet wide and 34 feet long. Pity the street tree.
In proper trim
Once the planting basics have been observed and the tree watered periodically but not excessively until its roots have developed, the most important element in its care is pruning. Correct pruning, that is. In spite of years of arborist outcry, misguided homeowners, handymen and landscapers routinely give trees a crew cut - "topped" in tree trade parlance - and this maiming lends itself to constant ugliness and future storm damage. The usual victims are crape myrtles, though cherry trees have been so abused in my neighborhood. I try to look away.
When a tree is young, you should prune out congested, crossing, inward-growing and broken branches, and remove any competing leaders to establish a strong central trunk. If you do this over the first two or three winters or so, you will be doing yourself and the tree a big favor.
It is easier to remove a nascent limb that is half an inch in diameter and at head height than when it is six inches across and 20 feet aloft. "If you invest a little time in the beginning, it has been found that the amount you have to pay for the pruning is significantly less than when it matures," said Mark Buscaino, executive director of Casey Trees.
High, wide and handsome
Trees need room, not just underground but above. This may seem obvious, but apparently it is not. Crowded trees grow unevenly and can get sick. This just in: Trees grow larger with each passing season. If you don't have space for a tree, don't plant one; put in a shrub instead.
What about trees that lean? Well, the forces acting on them certainly aren't in their favor, but here are the ones to watch: tall shade trees that were upright before a storm but lean a little afterward. Their anchoring roots have gone from constricted to kaput, and once the tree's center of gravity moves outside its own column, watch out.
Some badly leaning trees grow merrily forever. I'm thinking of the river birches and sycamores that extend over streams and small rivers. They started growing toward the light when they were small, and the roots developed simultaneously to allow the cantilevering. These leaners grow under the good graces of the trout gods and are blinged with lovingly tied fishing lures.
My mother has an old apple tree that grew askew some 40 years ago. No one saw fit to straighten it. It is none the worse for the leaning - each fall it is full of grand cooking apples that you could not find for love or money in these parts - but the crookedness precludes any sort of remedial pruning. The tree thus consumes much of a small space. Perpendicular trees are more soothing to look at and less prone to tip.
Planting a tree straight is harder than it may seem. Once you have the planting hole the right depth - so the flare at the base of the trunk is about two inches above grade - you should call on an assistant to view the trunk from several feet away. Have stones about the size of potatoes handy. The helper views the trunk from the north or south. When the tree is straight, wedge a stone between the root ball and the side of the hole. Here's the clever bit: The helper now looks at the trunk from the east or west, to direct a second alignment. Wedge in another stone, and with the tree sweetly upright, backfill the hole.
Newly planted trees often shift over the winter with the freeze-thawing action of the soil. Go back in March and reset the root ball if necessary. Mulch sparingly and, please, avoid mulch volcanoes.