When we moved onto our "town" property 14 years ago, the three big, old apple trees had not been pruned in quite a while. Since we had no experience with that we sought out some expert advice.
In our area, the Home Orchard Society is a great resource. We went and got a little tutorial to help us get started. I thought I would share some of what I learned then and have picked up over the years. I am no authority, so I will offer it up in the spirit of conversation rather than education.
I took away three big lessons:
-The right time to prune is when your pruners are sharp. This means that it is better to prune when you can then wait for the perfect time of year. Apple trees are very forgiving. I just finished pruning my trees today, and it is certainly not the best time of year. Each branch that falls through the tree after I cut it hits others, potentially damaging the fruit buds that are showing now. But now is when I can do it, and it is more important to lighten the load and avoid limbs breaking than worry about getting every apple possible.
-Give yourself 3 years to reign in an overgrown tree. The overgrown tree has a root system big enough to feed the whole mess of a tree. When you prune you do not diminish the energy the roots are going to push into the tree, so there will be more energy than the now-smaller tree needs. That energy will turn into massive new growth. Figure out how much you want to take off the tree, and do 1/3 of it each year for 3 years.
-Take out limbs, not branches. With one cut you can take off a limb with several branches and tons of twigs. Try to cut out the biggest wood you can. It will save you time and effort. And since new growth will come where you have pruned, one cut at the trunk will inspire less new wood than a bunch of cuts along the length of a branch.
When shaping your tree you want a nice, open structure, with good airflow, no branches rubbing, and no branch shading another. I also try to be aware of potential weight on the branches, because when they are laden with apples it adds a lot of weight, which can cause the branch to break.
Keeping them high enough above the ground is a big deal too. You want to make it easy to get under the tree for mowing, walking and picking. I sometimes get a little stingy, trying to keep more apples than I should. Phoebe did a nice job of pruning them up last year, when I was letting them hang too low.
The basic tools I use are hand pruners, loppers and a pruning saw. A chainsaw on a stick can be very handy, depending on the height of your tree.
And you need a way to get into the tree. Phoebe bought me a 17' orchard ladder, which is a fabulous tool for these big trees. Orchard ladders have 3 legs, which gives you a stable platform on uneven ground. I wish I had a shorter one too, like a 12', for getting in around the base of the tree.
Here is a look at a spot where I made a bunch of cuts. Mostly I removed branches that were under others, and therefore shaded by them. My goal here was primarily weight reduction, but the improved airflow should make the apples happier.