Wednesday, February 25, 2015

Pruning 101: 6 Easy Steps to Pruning your Trees and Shrubs

An edited excerpt from Food Not Lawns, How to Turn Your Yard into a Garden and Your Neighborhood into a Community, by Heather Jo Flores

To Prune or Not to Prune?
If you grow fruit trees or woody perennials, you will need to decide how to care for them. It is always a good idea to mulch around fruiting shrubs or trees to provide them with nutrients lost in the harvest. But what about pruning? As you consider how intensively you want to manage your landscape, it helps to consider death as integral to the cycle of life. When we try to grow our food as naturally as possible, we feel a certain relief that we are following the ways of nature rather than attempting to dominate or control it.

When a plant sheds limbs, leaves, flowers, and seeds, a life cycle per- petuates itself. We humans are simply a part of that process, and we can benefit from tuning in to the cycle as a whole rather than trying to make it work for our needs alone. So when you’re asking the question Should I prune my grapes? try to see yourself as the willing servant to the garden, not the master.

Trees prune themselves in a variety of ways. If a tree is too dense, disease may kill a branch. If the fruit load is too heavy, a limb may break off. Fire, wind, and floods are also natural agents of pruning. Left to themselves, trees often regulate themselves better than we do. In fact, most fruit trees will grow and produce quite well if never pruned. Often, the need for pruning is the result of unskilled pruning in the past. Masanobou Fukuoka experimented with letting older trees go wild and found that the more a tree has been pruned, the more likely it is that it will need pruning in the future. 

The reasons to prune are as many and varied as types of trees. The most common ones are disease prevention, fruit production, creating access to fruit, tree size, and aesthetics. Pruning removes dead or dying branches and allows for better light and air penetration, which improves the health of the tree and the quality of the fruit.
Some trees, such as figs and cherries, simply do not need pruning, and unless you need to repair damage from a windstorm or a bad pruning job, you can let well enough alone. A simple rule of thumb is to let the tree dictate its own form. By working with the tree’s natural tendencies you can encourage a healthy, fruit-bearing tree that requires less work and pruning in the long run. Here are some basic guidelines to help you prune as naturally as possible.

Pruning Tools
You will need hand clippers for the small stuff, loppers for branches up to half an inch in diameter, and a small curved saw for branches up to three inches; if you’ll be performing major surgery, a bow saw is helpful. I really don’t recommend chain-saw pruning, and while long- handled or pole pruners can make it easier to reach those high branches, the novice pruner will always do a better job from close up. Get up in the tree and have a look!

Sharp tools are essential. Just like humans, trees heal much better when cut with sharp, clean blades. A sharpening stone should be included in your tool kit, and many people carry rubbing alcohol and a rag to wipe their blades between trees, preventing the spread of disease.

The most common time to prune is late winter/early spring. Spring pruning encourages growth, and fall pruning discourages growth. In the spring prune before the sap is running so that the tree does not waste energy growing branches that will just be cut off. Spring is the best time to work on the overall structure of the tree and encourage growth in desirable areas. This is the time for major surgery, while the tree has the entire growing season to recover. The tree will send its energy to the places where you made cuts to heal them, and often “suckers” will sprout from those points. This is why, if you go out to your apple tree in the spring and cut off all of the vertical suckers, you will just have to do the same thing next year.

Some results can be achieved only by pruning in the summer or fall. However, it is generally not a good idea to prune heavily just before a major frost, because the tree will not have a chance to recover in time to withstand the extreme cold. Late-summer or fall pruning allows the cuts to heal over before the strong push of spring and does not encourage suckering. This is a good time to remove those pesky suckers, and if you wait until after harvest, no fruit will be wasted. It is always a shame to cut off a branch that is loaded with little unripe fruits!

Making a Proper Cut
This is very important. It is possible to kill a tree with bad pruning, and the most common cause of this is a bad cut that becomes infected. For small branches, cut back either to the branch junction or to within one- quarter inch of a dormant bud. The new shoot will grow in the direc- tion the bud is facing. Larger branches are usually cut back to the branch junction.

Cut right up to, but not into, the branch collar, which is the raised ridge in the bark near where the branch comes out of the mother branch or tree trunk. Cell division occurs rapidly in this collar, sending out healing tissue to cover the wound. Do not cut off any portion of the branch collar, but don’t leave a big stub either. Try to find a balance.
Cuts should be clean. Tears in the bark of a tree are very vulnerable to infection, so it is often a good idea to make an undercut one-third of the way through the branch from below, then saw the rest of the way through the branch from above. If you do have a tear, try to clean it up by making a new cut.

6 Basic Pruning Steps

1. Stand back and observe the tree as a whole. Repeat this step every three cuts to keep a perspective on the overall form. Yes, this means you may be climbing into and out of the tree several times during the pruning process.

2. Take out the “D’s,” in order: Dead, Dying, Diseased (moss and lichen are not disease, but fungus often is), Damaged, Dangerous (like limbs about to fall on the house), Doubling (two branches growing out of the same spot or rubbing on each other), and Deranged (bad angles, branches twisted around others). Stand back and look at the tree. If after removing the D’s you have cut around a third of the tree, you are done. Wait until next year to make any more corrective changes.

3. Choose your leaders, or main vertical structural branches. These will form the basic structure of the tree and can range in number from one to five. Choose vigorous, healthy branches that will support good horizontal branches. Allow ample space between the leaders and remove any other ver- tical branches. Stand back and look at the tree.

4. Choose your horizontals (branches growing from the trunk of the tree at an angle greater than forty-five degrees). These form the “scaffold” of the tree and will support most of the fruit. Choose healthy branches with good fruiting spurs. Choose branches that give an overall desired shape and allow easy harvesting. The lowest scaffold should be at least three feet above the ground, for good airflow. There should be one to five feet between each level of scaffolding. Stand back and look at the tree again.

5. Thin for air circulation. Remove any horizontal branches growing toward the center of the tree. Take out up to half of the vertical suckers, leaving the ones that fill gaps in the tree. Remember that these branches will eventually be weighted down with fruit and will fall into a horizontal posi- tion, so make sure there is room for them. Again, stand back and look.

6. Finally, prune twigs to encourage horizontal growth. You can often change the direction of a branch by pruning back to a bud that faces in the direction you prefer.
Remember, never cut off more than one-third of the tree in any one year. This includes the trunk, so choose your cuts carefully. It is generally better to make a few large cuts than many smaller cuts, to minimize the shock to the tree. Be patient and watch how the tree responds to your cuts throughout the year, so that you can make better decisions next time.


Sara Killinger said...

Your second pruning step about taking out the "D's" was a clever way to prioritize which branches should be pruned first. I have an elm tree in my backyard that has a few dying branches that are at risk of falling onto my vinyl fence. What is the best way to remove branches that are very high up and can't be reached? Tree Trimming

Jackie Oliver said...

My husband and I just moved to a new house, and the yard need some serious work. The shrubs are awesome, but they are way too overgrown. I really like what you said about stepping back, and looking at the entire tree and bush, and see what your goal is. That is such a great place to start, so that you know where to end up.