   Deciduous Fruit Tree Pruning - January 28, 2009 Jeff Schalau, Associate Agent, Agriculture & Natural Resources University of Arizona Cooperative Extension, Yavapai County Deciduous fruit trees benefit from yearly pruning throughout their productive lifespan. However, it is difficult to describe the pruning process in writing. Each tree has individual characteristics that make it nearly impossible to generalize. In addition, there are multiple approaches, most of which are valid and dependent on individual preferences. I’ll do my best to provide theoretical information in the remainder of the column, and then invite you to one of the workshop demonstrations that I have scheduled. At one of these workshops, you can watch as we discuss the principles of fruit tree pruning Pruning is critical to maintaining deciduous fruit tree vigor and training it to create a desirable structure. That being said, no pruning should occur without good reasons to do so. Winter pruning often causes a tree to respond vigorously, too vigorously, in cases where large quantities of material are removed. Conversely, summer pruning does not cause as drastic a growth response and is often used to remove materials without initiating as much regrowth in the form of undesirable water sprouts. Some fruit growers prefer trees that are trained to a central leader. This is most often used with apples and pears and requires removal of unwanted branches from the trunk while leaving behind strategically spaced side branches (scaffold branches). Open-center (also called “vase-shaped”) pruning removes the central leader at a very young age (preferably right after planting) to create a tree that spreads outward from the trunk allowing light to penetrate and air to circulate in the center of the tree. Open-center is often used for peaches, nectarines, plums, and apricots. It can also be used on apples and pears to keep the tree dwarfed and easier to harvest. This is usually considered a plus for backyard fruit growers. Pruning should remove crossing and inwardly growing branches. Sometimes fruit trees have been neglected and require extensive pruning. In these cases, I recommend addressing the most crucial problems first and leaving the less important issues for summer or next year. As a general rule, you should not remove more than one-third of the canopy in any given year. Peaches and nectarines are and exception and more can be removed from these species. Most apples and pears produce fruit on spurs: shortened twigs where flowers are produced. These spurs live from 5 to 12 years. Plums, apricots, and cherries produce fruit on shorter-lived spurs. Peaches and nectarines produce fruit predominantly on the previous year’s wood. This is critical in planning your pruning strategy for each of these species. In general, peaches and nectarines should be pruned more aggressively than the others to produce the desired quantity and quality of fruit bearing wood. The others can be pruned to control the number and age of fruit producing spurs. Large pruning cuts should be kept to a minimum. These cuts take longer to heal and will often cause water sprouts (vigorous vegetative shoots) to grow in that vicinity during the following growing season. If you must make large cuts, do not use a pruning sealant or wound dressing. Simply allow the cut to callous over naturally. Finally, use only clean, sharp pruning tools. Soak the loppers and hand pruners in rubbing alcohol for 5 to 10 minutes between trees and especially after pruning diseased material out. I’d like to invite you to join me for a fruit tree pruning demonstration. I will be conducting these at: the Kleck Home Orchard, 575 S. Gloria Lane, Cornville on Saturday February 7th from 10 am to noon and the McLandress Home Orchard, 850 S. Maricopa Street, Chino Valley on Saturday February 28th from 10 AM to noon. For maps and details about these fruit tree pruning demonstrations, visit the Yavapai County Cooperative Extension Web Site at: cals.arizona.edu/yavapai/. The University of Arizona Cooperative Extension has publications and information on gardening and pest control. If you have other gardening questions, call the Master Gardener line in the Cottonwood office at 646-9113 ext. 14 or E-mail us at cottonwoodmg@yahoo.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://cals.arizona.edu/yavapai/anr/hort/byg/. |