Mrs. Robin is not happy. She’s flitting anxiously from the porch railing to the lilac to the willow tree, scolding me the whole time in a series of loud cheeps. As I study where to make pruning cuts on my overgrown apple tree, I know why she’s upset. This is her place. For three years now she has built her nest in this tree, and in a few weeks she’ll want to do so again. It’s prime real estate: the bird bath where she likes to make her morning ablutions is in the flower garden just across the path, there are lots of worms in the lawn under the tree, and the thick, twiggy canopy is ideal for sheltering her chicks from heavy rain and marauding blue jays.
Unfortunately, that thick, twiggy canopy is just the opposite of what I want. There’s an old rule of thumb for pruning: a robin should be able to fly through the branches of an apple tree. For ideal production, the more sunlight that reaches the fruit, the better, and good air movement helps keep fungal diseases down by drying the leaf surfaces.
I didn’t have a chance to prune my apple trees last year. The work needs to be done when the weather has warmed enough that temperatures are unlikely to drop below zero, but before the buds start swelling for the new growing season. In my area of Maine, we usually have a narrow window in late March and very early April when the conditions are right. Last year, though, the snow was still three or four feet deep at this time, and we had icy winds, too. When winter finally broke toward the end of April, it was far too late for pruning. Then we had the most wonderful season for apples we’ve ever had, the trees laden with big, beautiful fruit. But that very bounty created a problem: some branches actually broke under the weight of all that ripening crop. So this year, I have major work to do.
This particular tree is a Jonafree, a variety developed from a cross between an old standard called Jonathan and other varieties. Like its parent, Jonafree tends to biennialism, or the habit of producing a heavy crop in alternate years with a much lighter crop between. Having produced such a huge crop last year, the tree would normally be taking a rest this summer, anyway, so I won’t be impacting my expected harvest too much by doing some substantial pruning.
I start by evaluating the major scaffolding branches, the skeleton of the tree, if you will. Over the centuries orchardists have developed several different “shapes” for scaffolds to promote both maximum penetration of sunlight into the interior of the tree, and ease of care and harvesting. The ‘open vase’ shape is widely used to shape other kinds of fruit trees, especially cherries, and although some old commercial orchards used the style, it has fallen out of favor for pruning apple trees because of the tendency of the main trunk to split down the middle as the tree ages. Another style is ‘central leader,’ in which the tree is pruned in a roughly conical shape, with the top scaffold branches about two-thirds the length of the bottom ones. This is the shape I’m aiming for.
The problem with diagrams and pictures, though, is that my trees never look like that. I have the same problem with cutting my own hair: I know the theory, but the results are often…infelicitous. Luckily, Nature abhors a bald spot, whether with apple twigs or with graying hair, and eventually the scalped place will fill in.
First things first. The broken branches are pruned back either all the way to the trunk for the most severely damaged or to a point where there’s good wood and healthy fruiting spurs, the little branches where the fruit will grow. That’s the easy part.
Because I haven’t headed, or cut off, the top of the trunk (aka the ‘leader’) in some years, my tree has gotten far too tall. I can’t reach the apples at the top of the tree even with a fruit-picker from the top of a stepladder anymore. This year, while the tree is resting, is a good time to do this major surgery.
Once the leader is pruned back, I start working on shortening limbs, especially the ones that are now at the top of the tree. This is necessary both to let more sunlight through to the lower branches, and to stiffen these smaller limbs so they’ll be able to support a good crop a year from this summer. As I work, I’m also pruning out branches that cross each other (so they don’t rub the bark off each other and give an easy entry point for disease), and ones that want to head downward instead of up or out. I try to maintain two to three feet vertically between scaffold limbs.
Major branch removal done, I switch from the pruning saw and bypass loppers to hand pruners to thin some of the twiggy growth. Jonathans tend to a lot of this, giving the effect of an old-fashioned twig broom at the end of the branch, and if some of it isn’t thinned, the apples will be far too closely spaced and therefore vulnerable to insect pests and disease.
When I am finally done, Mrs. Robin is still hovering. “Well, I tried to leave enough of a thicket around your nesting spot, sweetie,” I apologize. “Yes, I know it looks bare right now, but when it leafs out I think it will be OK.” She flits off. When I come back after hauling the trimmings to the brush pile, she is sitting up in the apple tree, preening in the March breeze.
I am forgiven, it seems.