Page 165 - 2017-greengate-Gardensense-magazine
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Most deciduous trees and shrubs are pruned in the spring, before they leaf out. Exceptions are birch and maple, which are pruned in July, after rapid spring growth finishes. They will drip copious amounts of sap if pruned in the spring. Shrubs that flower in the spring on buds that are formed in the fall, such as Nanking cherry, lilac, some roses, and white flowering spireas, are pruned after they bloom. Shrubs that flower in the summer, such as pink flowering spireas, most shrub roses, and potentilla, are pruned when green buds appear. Any winter tip kill is removed and branches trimmed to an appropriate size and shape. Pine trees and shrubs have new growth called candles that are snapped in half in June to make a somewhat bushier appearance and compact shape. Spruce trees are rarely pruned, although many people remove a few of the lower branches when most of the needles have died. Junipers and cedars may be sheared a little, but remember not to remove too many new needles.
Pruning shears are used for small cuts and should be sharpened frequently enough to make clean cuts. Somewhat larger branches may be removed with lopping shears, or a saw. If a large branch is to be removed completely, make an upwards cut a foot or so beyond the trunk, half way through the branch. Then cut downwards further away from that cut. The branch will break off when it is being cut downwards, and default to the upwards cut, but not damage the trunk. The final cut can be made without ripping bark off the tree as it falls.
Keep pruning tools clean and sharp. If the tree is diseased, clean after every cut by dipping into a solution of one part bleach to ten parts water. If you are not sure how to prune your tree or the size of the job, call a certified arborist.
Trees are so often planted in the wrong places, with little or no thought to mature size, that the answer seems to be to prune it to keep it small. This is a short term, frustrating solution that ultimately doesn’t work. Trees are genetically programmed to reach a certain adult size. Removing a large proportion of the branches means that the tree has fewer places to put needles or leaves that are necessary for photosynthesis. The roots absorb water and nutrients from the soil, but there aren’t enough leaves or needles to absorb sunlight, which the plant needs for survival. Often, it is better to replace a tree that is outgrowing its space with a more appropriate tree.
Spruce trees are a perfect example of this. Those cute little trees that look so perfect in a flower bed will grow to twelve feet wide and thirty-five feet high! The needles on the inside of the tree die every fall. This is a natural occurrence and not an indication of poor health. Each spring, new needles grow on the tips of the branches. If these are removed, as the oldest needles die, the tree will resemble a telephone pole with green needles only on the ends of the branches. If a branch doesn’t have enough needles, it will begin to die.

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