Pinus Nigra Hornibrookianna

bonsaichile

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I assume you are referring to Pinus Niger, Austrian Black Pine. As a single flush pine cutting back to one pair of needles after the candle has extended is risky. Normally one would leave half or one third of the candle, Partial decandling ( what you have described) is to shorten internodes or create bifurcation and is not cutting back to produce back budding.
Cutting back involves removing new growth and cutting back into old growth.

To begin with i will assume by ABP you are referring to Austrian Black Pine a specific variety of Pinus Niger. What you have described as a method is partial decandling. You have left some of the new candle and this resulted in new buds on the remains of the current years shoot.
The best way to encourage new buds in the interior of the tree is to provide as much light as possible to the interior. Branch cut back and needle pulling are the primary methods used to accomplish bud back closer to the trunk. Other factors include suppression of auxin by wiring the branch in a downwards direction and positioning the bud tips outwards not up.
I use the term cut back to reference the practise of cutting the branch back into old growth to promote needle buds further back on the branch as well as adventitious buds through selective needle pulling. The timing that i prefer for this work is late fall through to early spring!
If one expects backbuding to occur then several factors are important.
Vigorous of the tree, younger branches with needles present, removal of enough needles to allow light and retaining strong needles in the sites you wish to encourage new buds. Other factors that can encourage back budding is wiring branches correctly when decandling or performing partial decandling to suppress auxin and promote side shoots.
One of the confusing factors is when the term decandling( which means removal of the new shoot) is applied to partial decandling ( retaining a portion of the new shoot). Single flush pines such as ABP are typically treated with partial decandling techniques.
Specifically the approach you described of leaving two needles on the new shoot is aggressive for a single flush pine and likely to create a weaker tree and a weaker response to new buds.
Thank you very much! This is really helpful!
 

River's Edge

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Thought it was time to post an update picture. We are about half way through the current growing season and recovery is well under way. it is time to position branches so new foliage is not shaded out, and remove some of the large collars this species tends to create in the whorls. First picture, to show foliage as progressing. Second picture shows branches shifted to provide more light and air movement. As well as a bit of downward movement for the remaining branches that may be part of the final design. ( some branches have been kept to help heal scars first. The upper foliage part is left to extend and help grow some taper in the new apex. Poor time of year for wiring so just branch positioning done at this time. Will continue to fertilise and normal care through to fall.IMG_0857.JPGIMG_0859.JPG
 

girv

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Thought it was time to post an update picture. We are about half way through the current growing season and recovery is well under way. it is time to position branches so new foliage is not shaded out, and remove some of the large collars this species tends to create in the whorls. First picture, to show foliage as progressing. Second picture shows branches shifted to provide more light and air movement. As well as a bit of downward movement for the remaining branches that may be part of the final design. ( some branches have been kept to help heal scars first. The upper foliage part is left to extend and help grow some taper in the new apex. Poor time of year for wiring so just branch positioning done at this time. Will continue to fertilise and normal care through to fall.View attachment 253711View attachment 253712
@River's Edge I am currently working on a ABP as well so very happy to keep up with this thread. I am curious why now would be a better time to remove branches vs. when dormant in the winter? Last time I did this the sap flow was very excessive.
 

River's Edge

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@River's Edge I am currently working on a ABP as well so very happy to keep up with this thread. I am curious why now would be a better time to remove branches vs. when dormant in the winter? Last time I did this the sap flow was very excessive.
Not sure where you got the idea i was removing branches at this time. I repositioned some branches and reduced knobs that were left from previous removal of branches. I always stage the removal of branches by leaving a knob, then return months later to remove and finish the cut for proper healing. This is not the best time to remove branches from pines.
I think if you look carefully at the first picture you will see that the area where i worked did not have a branch sticking out, it was removed earlier. The area i worked on was a stub with a larger collar.
 

WNC Bonsai

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Ok @River's Edge after reading the recent thread on single flush pines I am in a bit of a conundrum over what seems conflicting info. Some sources indicate they should be pruned back to stop auxin production at the terminal buds and release back buds. Others say the only way to get back budding is to let the trees growing like crazy to promote back buds. At this point I have only gotten what I would consider to be 4 back buds and those aren’t that far back. Last fall I did some moderate pruning as you may remember from the discussion above and then mid-summer cut back the candles after they extended. I got tons of buds at the bases of the cut candles so am set for another profuse flush of growth next spring. So I guess the question is would it be better to just let them all extend and grow profusely to encourage back buds or should I prune them back again and fertilize heavily? Someimte I wish I had bought a Scots’s Pine, they seem to back bud quite well.
 

River's Edge

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Ok @River's Edge after reading the recent thread on single flush pines I am in a bit of a conundrum over what seems conflicting info. Some sources indicate they should be pruned back to stop auxin production at the terminal buds and release back buds. Others say the only way to get back budding is to let the trees growing like crazy to promote back buds. At this point I have only gotten what I would consider to be 4 back buds and those aren’t that far back. Last fall I did some moderate pruning as you may remember from the discussion above and then mid-summer cut back the candles after they extended. I got tons of buds at the bases of the cut candles so am set for another profuse flush of growth next spring. So I guess the question is would it be better to just let them all extend and grow profusely to encourage back buds or should I prune them back again and fertilize heavily? Someimte I wish I had bought a Scots’s Pine, they seem to back bud quite well.
I get the confusing part with how you express the concepts.
Pruning back to create a response will get different results based on where you cut back to. Cutting back to the base of a candle. ( decandling) produces buds at the base you cut back to usually and possibly a few back buds. Cutting back beyond the base but still in the area of viable needles, removing the apical candle and the auxin promotes more back budding ! This is usually done after allowing the branch to grow out and extend! This promotes a stronger response when cut back and some back budding due to vigour. Other factors encourage back budding as well, thinning needles to allow light into the interior.
So in short, the things you have retained are all involved, just need to be put together in the correct order to get the response desired.
Single flush are not usually decandled, the candle is usually pruned a certain amount but not removed entirely! Unless the goal is to reduce the overall length and create back buds further in the interior.
The process involves a number of steps and combined techniques. Focussing on one part does not reveal the overall approach! Hope this helps, personally i found the best way to learn complicated processes was hands on with a teacher and guided practise! it is difficult to take the time to include all aspect, edit all phrasing in text or short video.
One short observation.
If i remove the candle or if i remove the same section further back beyond the candle, then i have removed the auxin in the apical candle. The difference is where the new buds will form.
 

WNC Bonsai

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OK, that’s news and makes good sense biologically. I have the needles to cut back to so next year after the candles extend I’ll whack them and we’ll continue the experiment. The tree still looks very healthy and has numerous terminal buds on every branch so it should be a profuse flush in the spring.
 

River's Edge

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Update on this experiment. Today i reduced some foliage, removed a couple of branches, reduced some stubs from previous cut back, did some bud selection and a bit of rough wiring. Remember this is just an experiment with a rough nursery tree to learn more about this cultivar! Not expecting to create a great tree!
So far it is evident that one has to keep on the amount of new buds and growth. Vigorous type. Also the active growth period seems longer than JBP, makes sense in that is more cold hardy! Lots of sap and softer bark than comparable aged JBP, more like white Pine in that respect.
Here are two pictures showing the before and after. I deliberately chose to leave several branches longer over the winter. Will reduce in the spring for further bud back and interior development.
 

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River's Edge

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Well here we are approximately 16 months later for an update. The tree grew well and responded with a lot of back buds. I have been able to cut back and begin to bifurcate the branches, the top transition is still developing. long ways to go but progress is being made. Hopefully you can see the difference! First picture before work, second after and ready for the season.
This will never be top tree, but I am enjoying learning about Pinus Niger.
IMG_1399.jpegIMG_1408.jpeg
 

Arnold

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I would change the planting angle and cut the straight cylindrical section and make it a moyogi
 

River's Edge

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I would change the planting angle and cut the straight cylindrical section and make it a moyogi
Yes, that is another possible route, and it would alter the viewpoint. I can see why you might suggest that.
Some things are not so obvious in a picture!
I do not think it would not change the straight section as it is over 10 inches in length with no movement! Depending on the depth of the planting it may expose or hide the inverse taper at the base caused by circling routes in the nursery pot! Another inherent weakness is the whorls of branches forming at common nodes with no back budding between the nodes, thus very even distribution of branches and asymmetry more difficult to achieve. I have also observed that the branches naturally form bulges at the base of the branch. Not very pleasing to the eye. If one were developing a serious tree they would have to address this natural defect in appearance.

As indicated in my first post of this thread, it was time to experiment with a variety I was not familiar with. My intention was to play with it to see how Pinus Niger Hornibrookiana responds to Bonsai techniques. Never really expected much from this material with the obvious faults from the beginning. The cultivar does have some better qualities in shorter needles and back bud characteristics. Plus it is a vigorous species! Has been used for stronger rootstock and is easily grafted.

This particular tree, I think I will make it a plain simple formal upright. The key characteristic of this tree is the straight trunk, might as well use that! After all, I did go to to some trouble to get the apical leader directly in line for a formal upright style! In the meantime I will continue the experiment and develop more branching for pads.
 
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