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Pole saw/pruners: While this particular tool is called the "stick of the devil" in some quarters due to its propensity to produce poor cuts and encourage poor pruning judgments, neither of those is the inherent fault of the tool — rather they are the result of impatient and unskilled users. It is certainly easier to make a poor pruning cut with a pole saw or pole pruner, but attentive users who work to get in the correct position can make excellent pruning cuts with this tool(s). As far as the poor pruning judg- ment aspect, users can certainly "malprune" a tree with a pole saw or pole pruner, but, once again, some knowledge of proper prun- ing and a willingness to get in the proper position can eliminate this problem. Chain saws: "Bringin' the power" is certainly needed in some pruning operations, particularly in larger trees, but chain saws should only be used in pruning cuts that require their power and chain speed. The reality is that even with the best of saw control, small-diameter pruning cuts done with a chain saw are going to be ragged and very poor quality. Larger-diameter pruning cuts that require a chain saw also require the operator's utmost atten- tion to detail and saw control to result in an adequate finished cut; and, should time allow it, might best be "finished" with a hand saw cut in the proper location once the weight of the piece is removed via the chain saw. LOCATION, LOCATION, LOCATION The most important thing to understand and implement when pruning is the location of the final cut. The final cut should be made just outside the branch collar in order to allow the tree to respond properly to the newly created wound. Cuts in the collar of the branch itself will slow the process wherein the tree puts tissue over the wound, possibly leading to decay into the trunk of the tree or parent branch itself. Cuts too far from the branch collar will leave a stub that the tree will have difficulty covering with tissue, and once again perhaps leaving access for decay or pathogens. In the event of a dead branch where the collar has extended outward on the dead branch tissue, often seen in oaks, the cut should still be made right at the edge of the collar regardless of whether it seems to leave an unsightly protrusion or not. BASIC STRATEGIES Pruning a tree may be done for many reasons — some have to do with the health of the tree, some have to do with the desires of humans. Regardless of the inspiration for the pruning, it should be done in a manner to cause the tree the least stress possible. While an individual tree's response to pruning will depend on condition, site, and species, in general, a younger tree will toler- ate pruning more readily than a mature tree. A basic guideline is that no more than 25 percent of a tree's living canopy should be removed at any one time; and pruners should keep in mind that pruning is certainly a case of "less is better" if possible. Un- less human-required pruning needs are involved, most trees are well served by simply removing deadwood, broken, and crossing branches — with the 25 percent rule in mind of course. Trees that are pruned at a younger age for good structure will require less pruning as they mature, which is an excellent point to make to the customer at that new tree installation. Pruners should at- tempt to keep in mind the "pruning cycle" the tree is likely to experience and "project" where limbs or branches may be in the future to remove possible problems ahead of time, along with de- veloping co-dominants and narrow attachment points. CUTTING, NOT TEARING The most common pruning cut in which a saw is being used is typically a 3-step process. First, an undercut is made into the bot- tom of the branch to prevent the falling branch from tearing bark into the branch collar. Second, a cut is made into the upper side of the branch several inches out away from the trunk from the first or undercut. This severs the branch, allowing it to fall free from the tree without any tearing, and leaving a ledge like stub that is then severed with the third cut at the edge of the branch collar, ending the pruning 3-step process. While this technique works very well with hand saws, users should keep in mind that it can be problematic when cutting larger limbs with chain saws — often causing the chain to be caught in the kerf of the second cut and pulling the chain saw with the falling branch. A better option A bark-free illustration of the underlying wood interaction between a branch and the trunk. www.landscapeirrigation.com Landscape and Irrigation May/June 2015 11