First post here on growingfruit.org – I posted up my question on Houzz, and then remembered that someone had referred me here some time back. Let me know if this should be posted in a different location.
The house we bought last year has a pretty sizable apple tree. I’d guess 20-24’ tall.
As you can see in the below picture, there is a lot of verticality/water sprouts in the upper growth of the tree.
Ideally, I’d dramatically thin the tree and reduce it’s height a fair bit to simplify maintenance and fruit picking.
I live in Colorado zone 6A where fireblight is a concern, and with the extended warm snap we had during February (now cold again), many of the bushes are starting to bud. I think buds were starting to form on this one, and will confirm tomorrow. Our wet season is mid-March through May. I will also mention there appeared to be some fireblight here and there higher in the tree last summer; however, I didn’t have a way to get to it, and was swamped with other move-in activities.
What is a good approach to thinning and reducing this tree this year? I don’t want to be so aggressive that I put the tree at risk. Any additional feedback on all the vertical sprouts?
Here is one pic… I have others, but as a new member, it will only let me post one.
What you want to avoid is chain pruning, meaning that you want to reduce volume during the summer during the height of the growing season and not during the winter when it has the energy to push out that many water spouts again. I don’t have a lot of specific advice to give you, other than watching a lot of YouTube pruning videos and cleaning it up later in the year.
MisterGuy – thanks for your response. I’ll have to look into chain pruning to better understand that. My understanding was that, especially given fire blight risk in the Denver area, that I should only do significant pruning during the winter.
Part of what I’m trying to understand is what the general approach would be. The whole top half of the tree is well developed water sprouts… would they ultimately all be removed with thinning cuts back to the lower structure… maybe leaving a few structural ones that are oriented well. I’m assuming I can only do maybe 1/3 of them this year? I think I read that with apples and pears, 25% would be the most you’d want to prune the tree in a year.
I’m also unclear if the sap has started to flow in this tree, given 3 weeks of relatively warm weather here. In prior years, I haven’t paid a lot of attention to the buds in winter, so I don’t know if these are present to this degree in winter, or if this is ‘spring’ in action (which it seems). I’ve attached a few photos – mostly silvery.
By chain pruning I just meant you can get in a cycle of water spouts every year if you ONLY trim in the winter. I think you can give it an aggressive prune now, removing up to a third. You will need to give it another hard pruning in mid summer, and will probably still need to chop it again next year.
I have dealt with literally thousands of apple trees much like yours. I suggest you start by removing uprights and training the tree to a weep by leaving all drooping (below horizontal) wood. There is a beautiful tree there within the riot of upright growth. Why are you so concerned about FB? I manage fruit trees in the humid northeast and FB is not even something I consider when renovating neglected old apple trees- I’ve literally never gotten strikes on trees early in the renovation process and this year is the first after 25 that I have a single apple I’m managing with serious FB damage- on big trees I usually just get strikes on small wood that don’t go anywhere.
You can’t kill that tree by removing too much wood- if you cut it to 5" diameter stubs it would throw out new growth and be the same size again within 5 years.
With healthy apples overgrown and neglected like yours I routinely remove up to 2/3rds the smaller wood the first year. With really tall trees I often reduce them by 10’ the first year as well.
Ecological Fruit Production in the North is a book with very good drawings photos and instructions on old apple renovation.
Big old trees can be pruned anytime- you just want to be sure with winter pruning (or any pruning while trees are dormant to fully leafed out) that there are still plenty of buds on the trees so there will be enough leaf buds to pull adequate sap through the tree without scorching the bark- but trees like the one in the photo can lose a lot of wood before that can happen. Summer pruning reduces the chance of scorching bark, I guess because the leaves are fully formed and pull more sap that budding leaves in spring.
I’ve done the first wood removal in old apple renovations all months besides Oct., Nov. and Dec.- but I’m sure the trees would be fine with any month of the year.
I don’t believe it has been studied, buy my extensive experience has led me to the conclusion- right or wrong, that, in spring, if there is not enough sap being pulled through the cambium on a warm clear day, excessive heat destroys cambium cells of exposed wood. It is a combination of the new exposure created by pruning and the lack of adequate leaf transpiration to move sap up and out quickly enough to stop cells from overheating. Newly exposed bark won’t suffer if sap is moving through it quickly enough and a skilled pruner develops a sense of how much can be safely removed.
Old timers used to paint trees white to avoid it- especially when butchering out of control old apple trees in a procedure called “dehorning”, in which huge scaffolds were cut back to up to 10" diameter stubs. On the bright side, I manage many ancient apple trees with severe and very old scorching wounds that continue to function well for decades after the fact- but such branches are still more likely to break in severe weather (more anecdote for you).
Very interesting phenomenon Alan. I am “dehorning” or “stumping” some old apple trees for friends- started one two years ago that got bark damage just as you described. Surprised me, wasn’t sure what was going on but I quickly painted it with white latex. These are three, four year projects on each tree, grafting over the stumps to better apples. Learning as I go. Friends had planned to cut these trees down so I have carte blanche to experiment.
Thanks all – sorry about the delay in response – had a sick kiddo this week.
marknmt - thanks for the reference material - good stuff!
Alan - thanks for your insight. I recall following some of your posts back on gardenweb, and it’s good to see you’ve migrated here!
I’ll look up the weep training. At this point, there is some question about the apples really being good enough to keep the tree, as several smaller trees could fit in its prime spot. In any event, a good opportunity to learn on this one.
I cut out about 1/3+ of the water sprouts last weekend… most of the ones I could safely reach with the ladder I have. Perhaps after the snow is gone I can climb it.
When you say smaller wood, what diameter are you usually referring to? Also, on the original thread I posted on houzz, one responder indicated that if it wasn’t a flush cut (i.e if you left any branch collar, which I have many, maybe 1/2-1"), it would immediately sprout. His other comments seemed on the mark, but wanted to confirm if this is accurate and I should be flush cutting?
When you reduce the height by 10’ and you haven’t removed all the water sprouts, does this mean you’re heading the sprouts back 10’?
As to the fire blight concern… yes, I may be overly concerned. After I managed to spread fireblight throughout a 5-year old honey crisp when thinning early fruit, I’ve been a bit cautious, since. At one point on the trunk, I had to shave down the outer layers and cross my fingers, as the fire blight had girdled the trunk and some of the limbs like 90%. Amazingly, the trunk survived. I also understand that Colorado is a particularly bad state for fire blight.
The person who spoke about the advantage of flush cuts was probably speaking from his own “logic”. All drastic pruning of healthy apple trees will lead to a vegetative response, although thinning, much less so than stub cuts, but when you remove branches, a flush cut is never recommended, and leaving a slight swelling (the collar) so as not to violate the supportive tissue from the trunk is standard practice for trained arborists. Less skill ones, sometimes out of fear of scorch, will leave stubs when they remove lots of uprights in a neglected tree. If by flush cuts the writer was speaking about not doing this, than I would agree, but his terminology is confusing.
Why would Colorado be more conducive to FB than more humid states? It is the combination of temps and humidity that cause it, to my understanding. If it worries you do pruning after all threat of rain.
When I said “smaller wood” I was talking about the wood attached to the big wood I remove in a renovation. Certainly most of my cuts are of big wood the first year, but it is hard to figure how much total wood you remove and easier to estimate the smaller wood. When I prune big apples to a weep, I don’t remove any living, weeping wood the first season, unless it is part of a strategic big branch I feel compelled to remove- Later I sort out excessive weeping wood to produce better apples and by the third or fourth year I have the fruiting wood in a cycle of rejuvenation, leaving a percentage of the annual shoots every season that arise from smaller wood. .
An established apple tree will almost always bear meaningful crops of apples more quickly than a new tree if it is in high vigor. In such a tree grafts take very quickly, becoming full fledged branches capable of heavy cropping in as little as 2 years. The only reason to cut a healthy apple tree down is if the rootstock is too vigorous. Dwarf trees are less labor intensive as far as labor to crop ratio. That’s why commercial growers grow bushes instead of trees these days. Thank God my clients prefer trees- partially because the deer prefer bushes. Full sized, 100 year old plus apple trees require a silly amount of labor and a skill set that is almost dead. As hard as I try to explain methodology, only experience adequately teaches that skill set.
