Home Is Where Your Trees Are

Pruning Your Shade Trees. Part 3

Finally, if the tree stands where traffic or mowing machinery must pass, eye it for ample clearance and prune accordingly. Better a few less branches than any bruised ones. Thus far we have generalized about pruning small deciduous trees. Evergreens call for different treatments, which will be discussed below. Pruning fruit trees, too, has special rules, which appear in a later chapter. Here it would be well to draw some distinctions about the pruning of deciduous species with various habits. The leafy sucker growths on elm trunks and branches, also called "hairs" or "feathers," are somewhat necessary to these water-loving trees, especially aloft, to keep them from dehydrating. They should be pruned sparingly. But all elms should be watched closely for deadwood, which invites the bark beetles that carry dread Dutch elm disease. Plane trees are vulnerable to cankerstain, a fungoid disease that is highly infectious, but less so in dead of winter. That is the only time planes should be pruned; and even then, disinfect the tools. Pin oaks put out laterals so closely spaced sometimes as to look overgrown, but these should be thinned with much caution.

This tree's branches support each other under loads of rain and snow. Willows, poplars, Russian olives, and some other softwoods can be headed clear back to their main stems, where they will bush out. This is called "pollarding" and is commonly done for decorative effect. Small species which flower early are best pruned after petal-fall. This gives them time to form new flower buds for next year. It holds good for shadblow, redbud, dogwood, fringe tree, hawthorn, magnolia, sorrel (sourwood), and mountain ash. Locusts are an example of trees that flower late and can be pruned in dormancy or after. Since they tend to spindle up and die in the tops, it is well to head back locusts - but not honey locusts - when young. In heading or topping any tree make a slanting cut, to promote healing and shed water. Gardenias and camellias can be kept under control just by cutting their blossoms. But your poinsettias will sprawl up out of hand if you fail to whittle them back two or three times between flowering and early autumn. Palms are pruned simply by removing dead fronds; bananas, after fruiting, by cutting the stalks to the ground, whence sprouts will produce the next crop. Evergreens (the narrowleaf varieties) up to fifteen feet seldom require pruning except for removal of breakage and deadwood, which is done at the trunk. Cuts on evergreens mostly heal themselves with the trees' own resins, but it does no harm to paint them anyway.

Top and side trimming, to keep young evergreens in hand, is done by lopping terminals selectively, not shearing to a line. Such trimming will help spindly, shade-grown evergreens fill out, especially if it is done in spring when the foliage is soft. Firs, pines, and spruces are best pruned in late spring after they have made most of their annual growth. Arborvitae, cedars, juniper, hemlocks, cypresses, and yews (including Taxus), which all grow continuously, can be pruned any time except winter, when cut ends may dry out or freeze north of Maryland and through the Plains States. When evergreens suffer winterkill, wait until new growth can be distinguished before pruning out the damage. If damage is severe, wait until the new growth provides shade against sunscald. Whitewash on the exposed stems, too, will turn off the heat. Mid-December is the happiest time for pruning hollies: they take it kindly then, and you can use the cuttings for Christmas greens. Prune to branch junctions or the foliage will densify and suppress next year's gay red berries.