Really? Have you tested this? You can't just say some cut paste has these magical properties to keep out all microorganisms. It doesn't work like that. Some manufacturers claim their cut paste seals off the wound so no microorganisms can get in. They provide no evidence. You need quite a neat tight seal to make it smaller than the diameter of a cell. Never mind the microorganisms that are already there.
Same with whatever molecule they put in to inhibit microbial or fungal growth. We can't even kill dangerous microorganisms in people with billions of research funds. Are you sure cut paste can do so in plants? Don't believe their claims. There will be microorganisms and there will be growth in the tissue that's decaying after you cut a branch. That you can get cut paste that has something microorganisms can grow on, that you put some growth inhibitor in that prevents microorganisms from growing on the cut paste as the medium, I can believe that. But you need whatever molecule you have as an inhibitor to diffuse into the plant tissue and be there in sufficiently high concentrations. Then you need several, as one won't target all microorganisms. And the ones that are really effective, they are way too expensive to put in cut paste (maybe not for bonsai, but who buys a tube of 300 dollar cut paste?) And even then it is not a sure case that it will actually work.
So they put some cheap stuff in the paste, make claims that it contains growth inhibitors (never mind they have 0% effectiveness), then they just sell it and people buy.
It would be stupid to make a tube that would cost 300 dollars, then test it properly, then find out it can't be shown experimentally to be beneficial.
You have your own opinion on what cut paste is good. Some other person swears by some other cut paste; it has to be rock hard. It is like religion.
I do agree that putting soft stuff on should be less harmful than putting hard stuff on. But we can't be sure until that's tested.
This is my last post on this subject.
Do I have proof? Whatever I say, you will poo poo it. I have results. I've been doing this with my azaleas for two years. No dieback. Maybe I'm just lucky. I don't have hundreds of cheap azalea to test this process. I have a few nice azalea. That I don't want to risk.
I have studied with a guy who went to Japan to study satsuki azaleas, exclusively. He was taught this regimen there. By the guys who produce the finest satsuki azalea in the world. Maybe they're clueless, I don't know. But their azaleas are incredible.
I didn't make this stuff up. I'm sharing what I've learned from people who do satsuki azalea at the highest level.
What I was told is that TopJin cut paste has antifungal and antibiotic properties. I'm sorry, the paper insert in the box is entirely in Japanese. So, I don't know what chemicals they've put in it to do that.
I don't think it's meant to be a systemic fungicide/antibiotic, just be a topical treatment. Much like you might apply iodine or "Triple antibiotic ointment" to a cut you might get. The idea us to kill whatever bad stuff on the surface, then seal it quick to prevent new bad stuff from gaining access. Which is why you do it "immediately". The 30 second rule doesn't mean that if you do 35 seconds later it won't work, it just means don't wait 30 minutes to do it! Make a couple cuts, seal them up. Then make a few more, seal them. And so on. Don't make all your cuts and then go back to seal them all. Seal as you go.
Look, I bought a $400 imported, quarantined tree:
I plan to make a shohin out of it. The trunk I want to keep is about 4 to 5 inches tall. I don't want any dieback on the trunk.
Here it is after the cutback:
That picture was taken after putting the grey putty on top of the orange TopJin.
Here's a picture after it popped back:
No die back.
In a week or so, I'll do it again, selecting which of the new branches are keepers. I left more branches than I needed, just in case I did have some dieback ( no techniques is 100 percent perfect), but I didn't have any.
Now, since it's not difficult to apply cut paste, nor expensive (TopJin is about $15 on Amazon, and you can use plumbers or electrical putty for the grey stuff) should I risk not applying it because you say it's not necessary???
Sorry, maybe it has no more effect than throwing salt over my left shoulder, I'm still using it!