Pear, Pyrus species - pruning
Correct pruning increases fruit size, sugar content and improves color and skin texture. Pruning for good light penetration and accessibility for thinning and picking improves disease and insect control because the sprays penetrate better. Correct pruning does require a lot of time. A large apple or pear tree may require 1 to 3 hours of detailed work. The time is well spent if you value the tree's beauty and the quantity and quality of fruit.
WHY Pruning, however, is applied similarly to all varieties, and in general they are treated and trained as stated for the Apple tree. The flowers are definitely borne on spurs. Pruning favors spur-production, but at no time should there be an excess in pruning.
WHEN Light summer pruning tends to check wood-growth and also favors the spurs. The annual pruning of an established tree is limited to the removal of crowding and crossing branches.
HOW The Pear tree is much more erect in habit than the Apple tree and often develops very narrow crotches; these are not as serious with the Pear as with the Apple, since the tree can more readily survive a break at this point. The pruner should aim to develop a semi-pyramidal type of tree, with a good framework of subordinate, lateral branches. Cutting back 1/3 of the elongated new growth favors the spur-formation at the base of each new shoot cut. The middle 1/3 of the shoot produces the best fruit. Also remove or thin out excess new growth, particularly near the center of the tree. Thinning out the top of the tree permits sunlight to penetrate throughout the tree;. this exposure of the heart of the tree is essential to ripening of the fruit. These spurs bear each year, unless injured by wind-whipped branches, disease, a careless climber, badly placed ladders, or by old age. Thinning excess fruit is done simply by removing some of the fruit spurs. Sucker growth is ever present, particularly within the center of the tree; this should always be kept in check or it will soon crowd the heart of the tree by either forcing the tree into height or subjecting the tree to the dread disease known as "Pear or Fire Blight." This is a bacterial disease and spreads readily when branches are too close together, as in the case of excess, central sucker growth. The "Blight" spreads by spores, often entering the flower blossoms nearest the outer part of the tree, or through open wounds of cut branchlets. When the disease is active it spreads downward toward the heart of the tree, killing first the leaves, then the twigs, branchlets and the limbs. It must be removed immediately by cutting well beyond the visible infection from 6 to 8 inches. It can be easily recognized by the dull, coppery appearance of the underside of the dead branches or limbs. Always clean the cutting tools; they may be coated with spores, and be sure to burn up the branches with the disease. This disease is one of the main reasons why Pear trees should not be trimmed too severely, for wounds invite the spores.
Fruit-loads on plums and cherries are not as heavy as those on pears and apples. Since they are apt to grow into a bushy shape no matter what you do, early shaping is important mainly to keep them from getting too wide or to prevent the branches from growing too close to the ground.
Some trees grow twiggy naturally, and certain apple varieties such as Jonathan, as well as many varieties of cherries, plums, peaches and apricots, need additional thinning of their bearing wood to let in sunshine to ripen the fruit.
Trees bear their fruit either on the limbs or on short, stubby spurs between the branches. Pears, plums and cherries grow mostly on spurs, peaches grow on one-year-old limb growth, and most varieties of apples are produced both on spurs and on limbs.
Because spur-type fruit trees make less limb growth, they need less pruning. Since this means considerably less labor for the orchardist, scientists have worked on breeding trees that produce mostly on spurs, and there are now many varieties of this type of fruit tree available.
When too many fruit spurs develop along a branch, cut out some of them to encourage bigger and better fruits on the rest. After a few years of experience, you'll be able to judge about how many spurs are right for the tree. Each spur will usually produce for several years, but then you should cut it off to allow a replacement to grow. You'll be able to spot the older spurs by their aging appearance.
Pears are not as difficult to grow as peaches, but in past years fire blight has killed off many of the trees. Now, thanks to more resistant varieties and a better understanding of the disease, this fruit is coming back in both large orchards and backyard gardens. Like most fruits, pears need a partner for pollination purposes, os always plant your trees in pairs.
Pruning back bare-rooted pear trees at planting time is important, and the rules are the same as for any other fruit. Usually, two-year-old, branched trees are the best kind to plant.
The training of pears in their early life is quite similar tot hat of apples. Prune the tree to a central leader for the first few years. After that, you can grow it with a modified leader, if you wish. The growth of most varieties tends to be upright, so direct your early pruning toward thinning excess branches and encouraging a spreading tree. An annual light pruning is preferablej to an infrequent heavy one for two important reasons: heavy pruning delays bearing, and it encourages fire blight.
Pears bloom and bear their fruit on the short, sharp spurs that grow between the branches. Spurs need regular thinning, and occasionally you should remove older spurs so they may be replaced by more vigorous ones. Thin out the small fruits too, if too many are set in any year.
Always be on guard for signs of fire blight. You'll be able to spot it easily, because the limbs, leaves and twigs look as if they have been held over a fire. If you see any infection, cut off the diseased limbs completely back into good, healthy wood. Remove them to a safe distance, and burn, bury, or otherwise destroy them, so that the disease won't spread. As when pruning any diseased trees, sterilize your gloves and all tools in a strong Clorox solution after pruning each tree to prevent spreading bacterial disease.