Controlling size, pruning, and maintaining fruiting wood


#21

The video is a great example of pruning to a vase shape. You notice the tree is already head high. Olpea uses string tied branches to create a more horizontal tree. My trees are also more horizontal because I need to start the branching up so high- to keep above deer and also to allow me to make critter baffles.

I assume that the more horizontal the branches are the stronger the branches need to be. The cut he makes about half way through the video is the kind that can weaken a branch where he removes a branch at a split of equal diameter branches, cutting out the more upright branch.

Because the scaffolds are at a 45 degree angel instead of 60 or further horizontal it is not such a problem. If he had removed the outer branch and pulled the interior one to a more horizontal position it would presumably make a stronger branch, but would be time consuming and not necessary for branches at that angle.

I’ve seen other guidelines that either don’t recommend heading back fruiting shoots or call it optional- I think of it as optional and potentially a way to reduce the amount of thinning needed. I would make sure I have enough flowers that survived winter before I did it if winter was harsh.

He suggests that 4 scaffold branches are optimal, but this is also an optional thing where I prefer 3 and some growers just use 2 in trellis supported v systems. I’ve heard the single trunk method I described is often used in Israel- so you can even grow peaches without any permanent scaffolds.

I prefer 3 because it is easier to keep the tree open enough to grow the best quality sun exposed peaches- Not so much with a very young tree, but by the time they are over 5 or 6 years old. A 4 scaffold tree dividing the canopy in perfect fourths like the points of a compass are hard to convert to a 3 scaffold tree- the scaffolds end up on one side of the tree.


#22

Chris

That is Dr Mike Parker from NC State in the video. I have probably watched that video a dozen times to clarify the proper way to prune my peaches. He has another video showing the pruning of two mature peach trees. I really like the form of the first tree in the video below, its low and flat and spreads over a large area. I hope to make all of my peaches to look like that tree. Mike does research and conducts seminars on growing tree fruit all over NC. I am very fortunate to have him conducting a peach and high density apple pruning demo at my place in a couple of weeks.

What do you think about the form of the first tree in this video?


#23

Good videos Blueberry.

I have little experience pruning peaches to a central leader, so I won’t comment on that. I more or less prune the way the extension agent in the video does, with a few exceptions.

First, as Alan mentions, I start my scaffolds pretty low. I’ve started trees with higher scaffolds and it’s harder to keep those trees as low. I also tie selected scaffolds fairly close to horizontal. This produces a scaffold nearly horizontal for the first few feet, then it turns more upward, where it wasn’t tied down.

As the tree grows I adjust where I want the growth to be by way of pruning. The new scaffold which turns upward will of course send out all kinds of shoots. One can simply choose which shoots to keep as extensions of scaffolds, and which to prune off. If the growth is too low, that growth will eventually be pruned. If it’s too tall, that too can be pruned off.

The weight of the fruit will pull the scaffold down some, but for the most part it bounces back after harvest (I’m referring to the scaffold, not the individual fruiting shoots.)

I prefer the almost horizontal angle of the scaffold as it leaves the tree. I think it produces very strong crotch angles w/ no risk of bark inclusions. It may be that Alan and I have discussed the strongest crotch angles in the past (it’s a bit fuzzy since we’ve had thousands of forum conversations over the years). I don’t recall if we ever came to a consensus on this.

I also try to prune somewhat narrow crotch angles which come off the scaffolds. I think it’s easy for people to neglect this. In other words I think there is a tendency for people to think they are home free once they get rid of narrow crotch angles for the scaffolds (where it attaches at the trunk) but I’ve found any narrow angle on the tree is subject to breakage (at least in our high winds).

Drew’s question is a good one about how to keep a tree within 8’. The difficulty in understanding is found in the assumption of how peach trees grow. The question assumes peach trees only grow at the top point where the last growth left off, however this assumption is not correct. A properly pruned peach tree will put new growth all along it’s scaffold (i.e. down low and clear up at the top). The very top growth will have to be removed to keep the tree at 8’, but there will be plenty of growth lower down, if the tree is maintained properly.

That’s why it is so important to keep lots of light in a peach tree. A densely packed peach tree is a death sentence to all the lower growth. Apple shoots will tolerate some shade, peaches won’t. My peach trees are fairly vigorous, so it is critical I prune at least twice a year to keep them open (although very young trees may only get one pruning per year).

I don’t crop my trees as heavily as the extension agent in the video. He mentioned an 18" shoot could fruit 4 peaches. I would only leave two fruit on an 18" shoot. This produces bigger peaches, but less overall weight on the scaffolds, so the scaffolds pull down less. I’ve fruited with the kind of density the extension man suggested, but it causes me too many problems. First, unless the variety of peach naturally produces really large peaches, the peaches will be pretty small at that density. Secondly, there is just too much weight on the scaffolds. I’ve propped up scaffolds to keep them from breaking in the wind because of too much fruit, and it’s a pain. I don’t have time for that.

I also don’t trim back shoots to strengthen them as the extension agent suggested. This may also be related to how many fruit the shoot is allowed to carry. With less fruit, there is not undue force on the shoot.

There is quite a bit of difference in cultivars regarding how upright the peach tree wants to grow. Some varieties want to grow straight up and you really have to work harder earlier to keep them low. Some are more naturally spreading (like Redhaven, Harrow Beauty, etc) and those trees are easy to manage and can be allowed a little more leeway on their upward growth. Regularity of fruiting also plays a role. A tree which is more hit and miss won’t have the fruit to pull it down, and so requires more aggressive pruning to keep it from going up. Donut peaches also want to grow straight up, since they don’t have the weight to pull the branches down. Years where all the peaches are frosted off require more heavy and frequent pruning to keep them low.

Peaches don’t send out new shoots from blind wood, as readily as other fruit trees. Because of this, if I want renewal wood at a place on the tree I will leave a stub cut (called a hat rack) which will throw out new wood.

That’s about all I can think of. Starting to ramble here.


#24

Olpea, of course you are right about crotch angles- I think the narrow angle causes the branch to push away from the trunk- but there’s another thing in play sometimes. More horizontal branches tend to grow less vigorously so there is relatively more connective tissue provided by the trunk, securely wrapping it around the branch.

As you know, I train and prune by ratios, partially because I need a long straight trunk on my trees before first branches. So I don’t train peach trees in the manner you do or the method in the video. I maintain a central leader tree for at least the first three years and remove any branches that form on it more than half and preferably a third the diameter of the trunk at the point the branch is attached to it.

It tends to be the narrow crotched branches that are excessively thick, so they have two things going against them as far as forming strong attachments. They are the first branches I remove. I don’t even choose my permanent scaffolds until the third year and don’t remove the leader above them until about the fourth.

I have seen other peach training guidelines recently that stress ratios as well. It used to be only mentioned in regards to apples and pears as far as material I’ve read.

There have long been some gurus that suggest training peaches to central leader for the first few years but I haven’t seen that much of that in recent years. The danger is excessive shade in the center of the tree and you almost have to summer prune to make it work.

It was wise of you to stress the importance of keeping scaffold branches open enough to get light to new wood throughout the growing season. It is the only way to keep peach trees low, productive and long lived.


#25

Olpea,

What is “blind wood”?

Mike


#26

Mike,

Peach trees are less likely to send shoots out of older peach wood. Even younger (smooth wood) is reluctant to send out new shoots unless there are some buds on the wood (Rough bark almost never sends out new shoots.)

Other fruit trees will sometimes send out what is called adventitious buds/shoots. In other words, if, say, a pear tree is growing vigorously, it’s not at all uncommon for the tree to send out shoots from smooth bark, where there was no visible buds the year before, called adventitious shoots. Adventitious by definition means, “by chance.”

Peaches are much less likely to do this. In other words, if there is not a dormant bud visible, it is unlikely a bud/shoot will form. As such peaches are much more likely to exhibit “blind wood” or wood which has nothing productive on it. Just bark.

Sometimes a lot of sunlight will produce a few shoots on the peach wood, but sometimes it just sunburns the wood (with our high temps here) and kills the bark. The best way to prevent blind wood it to prevent it from being overly shaded in the first place. That and leaving a few stub cuts where you need some new shoots. Some varieties are less responsive to sunlight, and therefore more prone to blind wood.

I totally agree with Alan’s pruning by ratio. Alan has written a paper on pruning where he offers a memorable analogy comparing the size of the scaffolds to the volume of traffic on a highway. I agree with this in so far as it can be applied to my own peach management. I try to choose the smaller shoots for scaffolds because large diameter scaffolds over dominate the trunk on peach trees. This has to balanced with the desire to choose early scaffolds at the right height and direction from the trunk, the first year (for me). I’d prefer to start cropping peach trees in year three, so it forces me to choose scaffolds somewhere during, or at the end of the first season, which can sometimes limit choices. Still, if I have a choice between choosing a larger shoot for a scaffold, or a smaller shoot, I choose the smaller, if possible.


#27

Olpea, interesting about scaffold choice, thanks for the info. On stub cuts my only concern is canker. Fungal canker. I have one tree with it, and read that leaving any wood on a shoot, could dieback and leave an opening for canker. And sure enough a small broken shoot was right where the canker formed.
I guess a stub cut would be longer. I’m not even sure how I left that shoot. I don’t think i did, I think it broke there, maybe my dog. i didn’t notice till the canker was there.


#28

Drew,

Canker can be a big deal. I think it is worse in cooler climates, but I get my share of it here. Perhaps in MI where it’s cooler, stub cuts would increase risk. My peach trees typically don’t get canker from stub cuts. Canker seems to show up more in narrow crotches, sunburned scaffolds, the trunk (down low), or from hail damage. We had a really bad hail storm last year, which chewed up the bark really bad. Most of the wounds healed but some wood developed canker from all the wounds. I plan to remove some of this wood because it is small wood and some of it has very large areas of canker.

So far, I haven’t gotten too worried about canker in general. I’ve had some at my smaller home orchard for years. If it’s on a big scaffold, I don’t even cut it off, but just live with it. It’s sort of a cycle. The canker grows a little bit, then the tree fights back in warmer weather and calluses over some of the canker. The next year it starts all over again. It doesn’t seem to affect the productivity of the tree. One tree has it so bad I’ve had to lop some scaffolds off, which does affect productivity. I need to replace that tree in the next year or two.

My opinion may change at the farm, where there are lots more trees. Perhaps the dynamics will be different out there because of the greater number of trees. I don’t want a canker city out there.

The dynamics could also be different for folks in cooler areas. Also vigor plays a role. Lower vigor trees are less able to repair canker damage.


#29

I’m confused, Drew. You mentioned fungal canker and I think of bacterial canker as the main issue that concerns pruning method and timing with peaches.

As far as stub cuts, to me the rule is if it is older than one year wood, best to prune back to another branch, except when dealing with spurs. Stubs in older wood often end up dying back to the next living shoot leaving it susceptible to fungus. One year wood has buds all along it so growth will occur at the bud immediately behind the cut. The only reasons to make cuts into such would for most species are to stiffen developing scaffolds or to encourage more branching. The reason for doing it to peaches has already been covered.

I grew peaches here for over two decades where I only saw bac. canker on older, neglected trees of poor vigor. The year before last I got hit with it at a couple of sites on young healthy trees. They came back well the following year, though. I’m actually not even sure it was bac. canker, but the bark became very rough with a lot of gummosis. I never submitted samples to a pathologist.


#30

Well I’m not positive but I was a professional fungal expert. I no longer have my microscope else i could tell myself. I think it is Cytospora Canker. I would say with confidence that is what it is. it’s pretty easy to spot spore formation of fungi. Google it for more info.


#31

Well I’m not positive but I was a professional fungal expert. I no longer have my microscope else i could tell myself. I think it is Cytospora Canker. I would say with confidence that is what it is. it’s pretty easy to spot spore formation of fungi. Google it for more info.


#32

Drew, I somehow short circuited my categorizations of canker and transferred cherry issues to peach issues. How could a bacterial disease and fungal disease be given the same nickname? Oh yeah, they both produce cankers.

Thanks for helping me get facts straight.


#33

Yup…

We plan and Mother Nature giggles.

Mike


#34

You got that right Mike! I don’t even want to mention how many times i get things mixed up. I also have bacterial canker on my cherry tree. Well one of them. the other is just 2 years old and doing OK (knocking on wood).
They are 35 miles apart so not worried about it spreading :smile:
The canker ridden one is at my cottage. I’ve given up on growing anything much there. Dogwoods (Cornus mas) do well there. Variegated plants that need less light do OK. Otherwise no. I do have a vacant lot on the island that is low and filled with wild brush/weeds, etc. It does get all day sun and I could grow a lot there. Anything really. But I would need to fill, and bringing a truck to the island costs $140.00 a trip, to rent the barge that can bring vehicles over… Not worth it to bring fill, and I need about 25 yards worth. Oh well, maybe one day I can afford it.


#35

Blueberry, most of my peach trees are 2 or 3 years old and I have attempted to follow the form on the video I posted. I am new at this but have come to realize that if you continue to prune to outward facing buds and branches, over time your tree becomes wider and wider. I remember seeing pictures Olpea posted on GW of peach trees on his farm. I would call his pruning style more like a platter than a bowl but his tree spacing allows for that. My peach and plums are on 9 foot spacing so I looks like I need to go with the bowl shape and even then I am thinking after a couple more years the trees will be touching.

I appreciate all the input. Chris.


#36

Chris, I have peach trees in similar narrow spacing and there is no need to make them go so wide. If you are not going wide though you need to leave fewer buds overall or you will get too many shoots and too much shading. I leave my shoots a lot shorter than in the NC guy mature tree video above, and I have lots of different angles, not just 45.

Scott


#37

Chris,

Maybe I do train to a platter. :smile:

I know on my backyard orchard, I planted my trees on a 20’ diamond, so that each tree has exactly 20’ to the nearest tree. Once the trees got mature, I had difficulty driving my ZTR mower in between them to spray, or mow. I still have difficulty with this, so I end up having to cut back laterals just to get in between the trees without knocking fruit off.

As an aside, this training method requires lower density, which I don’t mind. I know this flies totally in the face of the industry (which continually pushes for higher and higher densities).

Higher density does produce more bu/ac for earlier yields. But so far, I’ve not tried to chase yields. My density is super low at roughly 100 trees/ac. Newer compact densities can easily approach 1000 trees/ac. Big deal. Those folks have to manage those packed in densities very closely to make everything work just right. The nurseries make a ton of money selling all those trees, and under intensive management I suppose the grower makes more money.

In a larger sense I’m not against agriculture chasing yields. Historically, it’s helped provide our country w/ a standard of living which rivals any nation. Nevertheless, I don’t mind trailing yields in this instance.

Here, land isn’t so expensive to have to plant trees with a "pack em’ and ‘stack em’ mentality. If I want more fruit, I can simply plant more acres. Even peach trees at 100 trees/acre will conservatively produce 300 bu/ac. That’s 15,000 lbs. per acre. Think about that for a moment 15,000 lbs! That’s a lot of food. Not 50,000 lbs. per acre, but still a lot of food.


#38

I’m with you Olpea, especially in home orchards. If you have enough space, and that’s a big if, I’d much rather avoid the claustrophobia of tight spacing. I used to try to plant trees from my nursery at 12’ spacing if it meant I could sell more trees. I soon grew to regret it. It just seems easier to produce the highest quality fruit if trees have enough space not to require extremely aggressive pruning during the growing season.

I think close spacing with dwarfing apple rootstocks is fine if you don’t mind growing little bushes- but I happen to love trees. You know those things that stand on their own, can grow above the deer and kids can climb on (adults too).

Obviously this is only an opinion and derived from someone that makes much of his living pruning fruit trees, but this is also how I feel about the trees in my own orchard. Trees need a lot of light and air to produce the best fruit, and in the northeast this is most easily obtained with generous spacing.


#39

I have no use for large trees. Or all the fruit they would produce. Little bushes, yes exactly what i want. I cannot care for a large tree either. That too is important. You should not have a dog if you can’t take care of it, same with large trees. Plus at my cottage I have large trees on my property. many over 70 feet tall. One was 120 feet but i had to take it down. At my cottage i can walk down the main road on the island and not see anybody at all. Just me and my dog, it doesn’t get better.

A lot of work maintaining large trees. The leaves alone. Notice the wood pile by the shed.

The road in front of my cottage. I’m forming a hedge of Cornus mas dogwoods. They were seedlings. Hard to grow anything there, but these seem to like it.

I’ll start a new tradition of making jam from the fruit, once the trees size up in a few years the fruit should look like this…


#40

No, I don’t like apple trees above 30 feet either. My bones are probably starting to get brittle.

Actually, I’m talking about trees that reach a height of not more than 14 ft, but trees on free standing rootstock. If it wasn’t for pesky critters, the height could be more like 10’.

Olpea, what is the ultimate height of your well spaced peaches?

One could plant the same rootstocks much closer but that doesn’t mean there would be less work if we are talking about stone fruit. For apples, I agree that planting on less vigorous rootstocks will lead to less work on maintenance. I generally can whip through apples on M26, even when fully mature and they require much less thinking in the process than same varieties on more vigorous rootstock.