1st dormant season pruning

Hi All, so, I'm waiting for the weather to get cold again (what a change from last winter) before I start my first season of dormant pruning. I was hoping to get some advice. My trees are freestanding on Bud.118. I have quite a few trees with significantly thick branches lower than 3' from the ground. I'm a bit nervous about pruning these thicker branches because their girth rivals the girth of the actual trunk. I'd certainly like to prune all branches lower than 3' but is it better to leave these thicker branches (I'm hoping for central leader style tree)? My second question: I didn't head back a few trees--for various reasons. Some of these trees (particularly the Domaines) are now essentially 7-8' tall whips--maybe one branch down pretty low. Can/should I head back these super-whips pretty low to try to get lateral branches starting at, say, 4' or is that doing significant harm at this point since?

HI Nat,

Yes, in my opinion, you should remove those branches, but only those below 2 feet. You don't say, but I am guessing your trees are younger (you say first season dormant pruning), so cutting off the thicker branches below 3' on a B118 tree is important to getting the CL style you're after and won't create problems. Especially where the branches are equal or nearly equal to the diameter of the trunk. The pruning can be done in stages over a course of years, but in all cases will allow the tree to release and develop height and a good set of scaffolds. To answer your second question: yes, head those trees, between 36-48", especially if they haven't begun to establish any lower scaffolds. The harder you head, the stronger the growth response. In both of these cases, I am always very happy to have the first set of scaffolds start at or about 24", so 3' may be a bit high depending on your objectives. Higher than 3' though is too high unless you have animals in the orchards, especially ones that can eat lower branches. Also make sure that your scaffolds are not attached at the same point on the trunk, you really want to establish whorls of branches so the trunk doesn't get choked off. Long term your trees will benefit from good pruning early in the life of the orchard. Don't wait to deal with problems you can identify today.

Mike Biltonen, Know Your Roots
Zone 5b in New York

There are many oft quoted rules that any branch should not be more than _ % of the trunk. All would agree larger than the trunk is a no no. I have not yet heard of a satisfactory argument for this, but we try to follow it anyway.

My coaching on pruning is to try and understand the cause and effect of an action, not rules. There are plenty of studies, for instance that shake out the fact that any and all branches will increase the girth of a trunk. Additionally, any pruning means less photosynthesis, and less growth overall...in all cases. If we are trying to turn a whip into a feathered tree, the heading Mike mentioned is the only route, short of chemical spray methods (altering auxin/cytokinin levels). If there is a good amount of lower branches on a given tree, it does also reduce sunscald, and certainly adds to growth and trunk girth. Cutting them because they are in the way, or look weird can certainly be reason enough for losing them. Side trimming any tree will result in more vertical growth for sure, but in something like a lanky whip, that could be trouble. My advice Nat, is to do both, head it, leave the lower branch/branches, and then when there are other candidates higher up and likely all the way around, cut out the material below. Eventually, anything lower than 4 feet will mean fruit on the ground on a long branch.

Walden Heights Nursery & Orchard
Zone 3 in Vermont

Generally, rules are borne of research, anecdotal observation or empirical evidence. What they are not is plucked out of thin air willy-nilly. The whole idea behind removing branches that are too large or dense is to allow for better partitioning of water, minerals, hormones, and carbohydrates throughout the tree. Removing branches equal to or greater than 2/3rds of the trunk diameter at the point of attachment is just good horticulture. The positive impact of renewal pruning has been demonstrated and proven for so long it shouldn't even be a debatable point. It may not fit with some production styles or philosophies, and that's cool, but to say it is not proven is wrong. Pruning doesn't mean less growth or Pn "in all cases." In fact, if the tree canopy is allowed to become too dense then the sunlight (that thing that drives photosynthesis) can't get to the interior of the tree, reducing photosynthesis, and overall growth. Yes, too much pruning can have a short-term debilitating effect on the overall physiology of the tree. But well timed and well executed pruning can actually increase growth and Pn in the season following pruning - meaning better productivity at the end of the season and in the long-term. Finally, starting your first bearing branches at 4' is OK, I guess, if you're 7' tall and/or have livestock roaming the orchard. But in most cases, starting your first set of scaffolds between 24-36" and combined with proper pruning will give you a tree with excellent tree structure, including limbs that are stiff enough to hold a crop of apples off the ground. You do need to develop your own technique and style over time -- but it is all just a variation on a theme. You're not reinventing the wheel. Think first, cut second. Understand, as Todd said, what you are doing. But by all means, don't ignore time tested and proven techniques to help you achieve what you've set out to do: grow good apples!!

Mike Biltonen, Know Your Roots
Zone 5b in New York

Perhaps we should be specific about this application. If we are talking about a young tree, even if it was not a 7-8 foot whip, photosynthesis is going to be higher overall in a tree that is not touched, particularly in the earlier months before a growth rebound. This will in all cases be a net loss of growth in the tree. Shading of the tree interior will be minimal.

In contrast, an older tree pruned properly will be a must, whether or not the net photosynthetic gain (pn) is compromised, because fruit quality, disease etc. will trump the equation.

As for that first scaffold, our orchard is now in the process of cutting out that lower growth. I am happy I left lower branches in those earlier years because it resulted in a good deal of fruit production, and I wound up with stockier trees. It was difficult, however, to keep the fruit free of disease, animal browse, and in many cases laying on the ground (pears especially with this last one). Also, it is dependent upon the culture of the orchard: ours is diversified with other plant species growing near the canopy. Herbacous ones like grasses and wildflowers are allowed a growing pulse, and so often grow several feet high. When a crop lets on, those lower branches on many trees are mushed up in the mix. A clean cut orchard would have less an issue, agreed. So, our management scheme, which I'd repeat doing, varied according to tree age. This means letting it all hang out in terms of early trees...little pruning save heading lanky varieties and cutting/spreading to avoid weak structure, and then changing the program sometime in those bearing years since its needs will be different.

Mike, as for "willy nilly", no offense taken, I like a good banter. This might be a good idea for another thread: citing sources, merits of observation, peer reviewed studies. Perhaps participants of the forum will be better served by adding citations.

Walden Heights Nursery & Orchard
Zone 3 in Vermont



Edited 1 time(s). Last edit at 02/07/2016 12:02AM by Todd Parlo.