Fill In The Gaps On Pruning Techniques

From The Fresno Bee, January, 21, 2010; byElinor Teague:

A couple of pruning terms seem to mystify many beginning gardeners. That's probably because they refer to parts of plants and trees that can be rather hard to see and identify. Branch collars and leaf scars are not always clearly visible, but knowing where they are is critical to proper pruning.

Branch collars are found on all woody plants. The branch collar is a raised, rougher-textured ridge at the base of a twig or branch at the point where it joins the parent branch or main trunk. A branch collar is aptly named; it really does resemble the ribbed collar on a crew-necked sweater.

When making pruning cuts, it is important to cut off a branch just to the outside of the collar--not so far from he collar that a stump is left nor so close that the cut removes part of the collar.

That's because the collar contains toxic chemicals that speed the growth of denser, protective tissue across the wound, healing it by sealing it off from disease, air and water. It is no longer recommended to use pruning paints or asphalt compounds on pruning wounds, since they interfere with healing.

You may not have recognized the collar itself, but you will undoubtedly have noticed stumps that have died back to the original branch base. It is good gardening practice to remove stumps.

Even when using sharp pruning shears or loppers, it's not always possible to make a clean cut at the collar, especially where the dead wood meets living tissue. A small Japanese pruning saw or even a box-cutter can provide a good clean cut to the surface.

After all the leaves have fallen from deciduous trees and plants in winter, it sometimes takes good reading glasses or even a magnifying glass to be able to see the leaf scars along the bare branch or, in the case of roses, along the canes. Leaf scars aren't very big or deep; generally, they're a small, darker, slightly crescent-shaped mark on the surface of the bark.

Leaf scars indicate the position of last year's leaves on the branch. This year's new buds, leaves, twigs or branches grow from the leaf scars.

Good pruning cuts direct new growth away from the center of a plant or tree. Making pruning cuts just above a leaf scar that points outward will maintain an open shape.