   Pruning Deciduous Fruit Trees - February 13, 2002 Jeff Schalau, County Director, Agent, Agriculture & Natural Resources Arizona Cooperative Extension, Yavapai County Have you pruned your deciduous fruit trees yet? If not, I'll give you some guidelines in writing, then tell you where you can go to attend a live demonstration. Honestly, fruit trees can be pruned any time of year. California orchards have been moving toward summer pruning for several years now. Most people prune in winter to see the branch structure and fruiting wood when the leaves are absent. Winter pruning also tends to invigorate a tree by encouraging vegetative growth. Pruning is not rocket science. However, you need good tools: hand pruners, loppers, and a pruning saw. A pair of gloves is also handy, especially if your tools are as sharp as they should be. It's also a good idea to soak your tools in rubbing alcohol for 10 minutes between trees, especially if you are pruning diseased trees. There are two general strategies that can be used in pruning deciduous fruit trees. Peach, nectarine, plum, sweet cherry, apricot, and fig trees should be pruned using the "open center" method. The "open center" strategy creates a broad vase-shaped canopy allowing in sunlight and improving air circulation. Increased sunlight creates stronger branches and a healthier fruit crop. Increasing air circulation reduces insect and disease potential. A yearly pruning schedule will keep trees producing and in good shape. Apple trees can also be pruned to an open center, especially if you don't want to climb a ladder to harvest most of the fruit crop. Conversely, apple, pear, sour cherry, and European plum (prune) trees can be pruned using the "modified central leader method." This method retains the main trunk in the center of the tree as well as some side branches. The side branches are called scaffold branches and should be selected based on their crotch angle and be evenly spaced radiating outward from the main trunk at different heights. The "modified central leader" method results in a sturdy tree that stands up well to harsh weather. Pruning cuts also come in two varieties: heading and thinning cuts. A heading cut is typically placed at the tip of a branch to encourage branching below that point. By cutting off the tip, suppressed buds grow out and produce new branches. Newly planted trees usually need to be "headed" to induce scaffold branching. Thinning cuts remove side branches (not tips) to open up the crown of the tree. Once a tree begins to produce fruit, you need to understand exactly where fruit is formed on the tree. Peaches, nectarines, and figs produce fruit on the previous year's wood. Apple, pears, apricots, plums, and cherries produce fruit on short spurs for a number of years depending on type of fruit. In general, peaches and nectarines need more aggressive yearly pruning than the spur fruiting trees. Ideally, large branches will never have to be pruned because we all prune our trees correctly each year and know exactly what we are doing at all times. So, if one of your neighbors asks you for advice on pruning large branches, do not let them prune it flush to the trunk or main branch. Instead, it should be pruned just beyond the branch collar (swollen area near). The resulting wound has a smaller surface area and will callus and heal over more quickly. By the way, do not use sealants to cover pruning cuts. They are not necessary and can cause decay if applied in thick layers. I could continue with more rules and techniques, but instead here is something to think about: never make a pruning cut without a good reason. Try to understand how trees grow and where they produce fruit. Finally, to learn more, attend one of the University of Arizona Cooperative Extension fruit tree pruning workshops. We always have fun and learn together. To date, I have three workshops scheduled. The Yavapai County Cooperative Extension web site (ag.arizona.edu/yavapai/) also has this information as well as maps to each location. If you can't attend a workshop, North Carolina State University has an excellent web site showing proper pruning techniques at www.ces.ncsu.edu/depts/hort/hil/ag29.html. Freitas Orchard Pruning Workshop 9:30 AM on Saturday February 23, 2002 at the Freitas Orchard, 1575 Paradise Drive, Cottonwood. Directions: From Highway 260, go west on Fir Street to 6th Street, turn left on 6th (this is actually Paradise Drive) and continue roughly 1/4 mile and watch for orchard on the left. Bent River Ranch Pruning Workshop 1:30 PM on Wednesday February 27, 2002 at Bent River Ranch in Clarkdale. Directions: from Main Street, Cottonwood, go west toward Clarkdale on Main Street for one mile past the old Mt. Hope Store, turn right on Bent River Road and follow signs, go ½ mile on Bent River Rd, take driveway on right, continue through cedar gate and park. Young's Farm Pruning Workshop 10:00 AM on Saturday March 9, 2002 at Young's Farm in Dewey at the intersection of Highways 69 and 169 on Saturday March 9, 2002 at 10:00 AM. We will meet at Young=s Farm Restaurant parking lot and travel the short distance to the orchard. The University of Arizona Cooperative Extension has publications and information on fruit production and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 or E-mail us at mgardener@verdeonline.com and be sure to include your address and phone number. Find past Backyard Gardener columns or submit column ideas at the Backyard Gardener web site: http://ag.arizona.edu/yavapai/anr/hort/byg/. |