I have a number of Japanese black pines that are transitioning from the development stage to the refinement stage. The trunk has thickened to the desired size and I’m starting to focus on branch development. As for the tree below, I’m happy with the trunk, but need to encourage the future leader to thicken. To do this, I’m going to remove the sacrifice branch that was used to thicken the trunk.
Black pine started from seed in 2004
In the photo below, you can see that the sacrifice branch is much larger than the future leader. The plan is to remove the sacrifice branch and let the new leader grow freely for a couple of years. Letting the new leader grow will both thicken the new leader and accelerate the healing of the wound left by removing the sacrifice branch.
Sacrifice branch and new leader
As the sacrifice branch was fairly large, I used a saw to remove it.
After removing the sacrifice branch with a saw
The callus that forms after making a large cut will create a bump unless the area is gauged out with a chisel or knob cutter. I used a chisel in this case.
After gouging the cut area with a chisel
I covered the wound with cut paste to facilitate healing.
Wound sealed with cut paste
Here’s what the tree looked like after removing the sacrifice branch.
After making the cut
As the needles on the new leader shaded the lower branches, I removed them to let more light in. I also repotted the tree as the soil had become compact.
After pulling needles and repotting
Here’s a close up that offers a better idea about what the future tree will look like.
The future tree
I expect the remaining sacrifice branch to remain in place for about two years. At that point I’ll determine whether or not it can come off. If it can, I expect I’ll be done with sacrifice branches on this tree and will turn my attention to branch refinement.
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Trent says
Jonas, thank you for this great post! I have a similar situation with a jbp that I need the trunk to thicken up a bit. I’m wondering what the care/maintenance is on the sacrifice branch while letting it grow. Do you decandle, bud select or needle pluck while letting it grow out or is it left alone altogether?
Jonas Dupuich says
Hi Trent – good questions. At first I let them grow. I remove needles and thin them a bit to let light reach the branches below and keep them from tipping over. As I get ready to remove the sacrifice branch, I’ll reduce them incrementally and occasionally decandle them to encourage more growth below.
Mac McAtee says
Jonas, Are you using electrician’s duct seal for cut paste? I have been using it for years and have found it to be a superior material for that purpose.
Wounds heal very well under it. It easily pushes off as the callus forms. It can be removed easily. At $3.75 for a one pound bar it is very economical to use.
I keep a small quantity in a wide mouth bottle in water. When you use it it comes out of the bottle wet and my fingers and thumb get wet so it doesn’t stick to them instead of the tree.
Jonas Dupuich says
Hi Mac – I haven’t tried the electrician’s putty yet. It’s on my list! I like the idea of keeping it in water so it’s easy to apply.
Charlie Mosse says
Good info and pix. Going to pass this on to the club.
PG says
Thank you for another great post. I’m a year or two prior removing SBs on my JBPs.
So far I’ve seen doing it in stages and leaving a stub for a year or so, hearing to avoid trunk die back.
You cleaned it right as once and forever, is it safe? Beacause I like it…
Jonas Dupuich says
Hi Peter – because there are branches around the trunk and a large branch (the new leader) close to the cut, I expect the wound to heal safely.
Josh says
Jonas,
I have seen several trees, including my own at Boon’s having the sacrificial leader removed with a “peg”(for a better term) left behind. It looks a bit like a chopstick in the center of the cut 1″long. Boon mentioned some continued sap flow, and improved healing. I’m sure there are many ways to skin a cat, comment on your choice here? Tree looks great, flush cut, taper, etc a nice set up for future tree.
Jonas Dupuich says
Hi Josh – great question. I asked Daisaku about this recently. He said on bigger cuts I could leave the stub for a couple of years and then remove it when the wound was mostly healed. I don’t know about sap flow – or how to test that – but “improved healing” is the reason I’ve most often heard for leaving it. My guess is that it provides a good shape to support the callus. Once the callus reaches the peg, it can be removed to allow the callus to completely seal the cut.
I didn’t leave a peg in this case because the wound wasn’t very big. We’ll see how it looks in a year or two. On a 2″ diameter cut I made with Daisaku, I left a peg. Thanks for asking!