Kotobuki Japanese Back Pine Decandling Help

[mister_project]

I planted a 5+ year old Kotobuki JBP almost 2 years ago. I let it get established the first season and didn't do much to it but have since started trying to refine it this year. I'm a novice, which I'm sure you'll see in the photos below, and I'm humbly asking for some input regarding decandling. I've read that JBPs are very unforgiving, so while I'm all for learning by mistakes I also don't want to kill the tree or maim it so badly that I lack the skill to fix it. Here's the tree shortly after I planted it.



My ultimate goal was to sort of try a niwaki-style approach with a slanting form. I'm not sure if "niwaki" is the right term since I'm not going for the puffy clouds look. I'd like more of the flat pad look in the end, so basically just a giant sized bonsai-styled tree.

I live near Seattle in zone 8B. The tree is on the west side of the house and gets hot sun beating down on it all afternoon and evening. It does have irrigation and gets watered regularly. I applied some very mild slow release fertilizer in early early spring of this year. I also thinned a few of the worst branches close to the interior of the tree. I'd guess it was <10% of the total tree cover, and I left a lot of sacrificial branches on to help thicken up the trunk. Lastly, I also started to tie the tree to pull it and the branches into better positions. I couldn't quite get all the way with some branches so I will have to pull them down bit-by-bit over the next few seasons until they are where I want them.

Ok, so here we are today and really to my questions about candles like the ones circled red below.



I didn't do any pinching in spring but am considering some very minor decandling on the branches that I've circled in red. They are much, much longer than almost all other candles on the tree. I'm mostly concerned about limiting the lengths of the upper branches of the tree so that the lower branches can catch up and even out the overall form of the tree. Here's another shot.



There are some long branches just below the ones I've circled red, however their candles are shorter, the needles look balanced and small, and the horizontal branches are starting to form the pad shape that I'm ultimately after. Am I okay to cut the candles?

I'm an engineer by profession and tend to over explain. Apologies for that, and thanks in advance to those who took the time to help examine my questions and provide some thoughtful insight.

 

[0soyoung]

As an engineer, you should first understand that what you do to one branch generally has little to no effect on the others, so you can experiment on one branch before you risk the whole tree.

The second thing (I think) is to know that decandling a standard JBP about 1 June will produce Kotobuki-length needles in our area --> really short Kotobuki needles.
Third, or the subpoint to the second thing, is that 'summer' bud/candles that come after decandling will not have any strobili. Hence you eliminate those long necks by decandling.
Forth, of the second subpoint, is that the needle length of 'summer' candles is controlled by the growing time left in the season. Hence you can tune the foliage over the tree by decandling the strong areas last (e.g., weaker in early May, strong/long late May, say).

So, you likely will want to decandle in early/mid-May to that your tree doesn't have the long necks on shoots. However, your one 'spring' candle/bud will quite often be replaced by two or more buds. You should reduce this to two to avoid making whorl knots in the stems. Of course this is going to make the branch ramify and is how you create a foliage pad. The downside is that you are going to see why niwaki looks 'pompom-ish', but you simply correct this by thinning out the branching. Then you get more of a bonsai-like pad structure (this and a bit of 'engineering').

 

[Adair M]

You have a Kotobuki. Which is a dwarf variety, and naturally produces short needles and many buds at each node.

Regular JBP, produce long needles and one strong bud at each node.

Can you see the difference?

Decandling a regular JBP can make it act more like a Kotobuki.

If you do the same thing to a Kotobuki that is normally done to regular JBP, you get extreme amounts of buds and hardly any needle growth.

So… don’t “decandle” Kotobuki. Instead, treat them more like you would a JWP.

See where you have lots of buds growing from a single point? Thin those back to two. You probably don’t want the longest and strongest, so remove those, and keep two of the medium or weak shoots. Choose two growing out sideways (rather than an up/down pair).

Thin out every junction so that there aren’t any “whorles”, just two branches at every junction.

 

[hinmo24t]

You have a Kotobuki. Which is a dwarf variety, and naturally produces short needles and many buds at each node.

Regular JBP, produce long needles and one strong bud at each node.

Can you see the difference?

Decandling a regular JBP can make it act more like a Kotobuki.

If you do the same thing to a Kotobuki that is normally done to regular JBP, you get extreme amounts of buds and hardly any needle growth.

So… don’t “decandle” Kotobuki. Instead, treat them more like you would a JWP.

See where you have lots of buds growing from a single point? Thin those back to two. You probably don’t want the longest and strongest, so remove those, and keep two of the medium or weak shoots. Choose two growing out sideways (rather than an up/down pair).

Thin out every junction so that there aren’t any “whorles”, just two branches at every junction.

i thought kotobuki was growing JBP on different or older rootstock?

 

[Adair M]

i thought kotobuki was growing JBP on different or older rootstock?

They are usually grafted, if that’s what you mean.

 

[mister_project]

You have a Kotobuki. Which is a dwarf variety, and naturally produces short needles and many buds at each node.

Regular JBP, produce long needles and one strong bud at each node.

Can you see the difference?

Decandling a regular JBP can make it act more like a Kotobuki.

If you do the same thing to a Kotobuki that is normally done to regular JBP, you get extreme amounts of buds and hardly any needle growth.

So… don’t “decandle” Kotobuki. Instead, treat them more like you would a JWP.

See where you have lots of buds growing from a single point? Thin those back to two. You probably don’t want the longest and strongest, so remove those, and keep two of the medium or weak shoots. Choose two growing out sideways (rather than an up/down pair).

Thin out every junction so that there aren’t any “whorles”, just two branches at every junction.

Awesome information. Thanks to you and others for your input.

I think I am following what you're saying. If I have 5 candles I should cut 3 off at the base to leave two smaller/weaker ones which point more sideways than straight out. I assume next year those two candles (or what used to be and is now a branch) will start another node with many candles. I will rinse and repeat seasonally until the pad is created. Do I have the gist of it correct?

If it's true that cutting one branch won't affect the rest of the tree am I okay to remove the extra candles now even though I'm probably a week or two late?