I had a thought. If you are not in a hurry, the trunk and most of the primary branches can be used, but the distance to the secondary branching is a bit long. Needles are long. What about grafting a shorter needled pine branches onto the ponderosa? If you had a stock plant around of the super short needled Japanese Black Pine cultivar. Or maybe P. sylvestris. I think P. mugo would also take, but there are issues working with mugo you might not want to take on. Heck, you could even graft on Japanese White pine. No reason not to try. Can you tell I took a grafting class last year? This week all bonsai issues look like they could be solved with grafting.
You will get some sparse back budding on wood less than a decade old with good fertilizing over a couple years, but rarely will the buds be exactly where you need them.
I have been warned to not work the Ponderosa's too hard until you are getting candles that turn into thick bushy fox tails of growth much like a JBP. If you are still getting only a few new whorls of needle bundles out of the new buds, the tree isn't established yet. Go gentle. My 100+ year old ponderosa from Andy took a good 5 years to get rolling. Now it seems indestructible.
Hi Leo, and Thanks for chiming in. I've got two Pondys now, this one and another styled for the first time last winter. So I'm still at the very early stages of development. I'm going to take a wait and see attitude re. finished needle length. I maybe happy with the final reduction size on a tree this size, but the second smaller one might indeed need some other kind of needle to be convincing. I just don't know yet, but feel there's no rush. I've got yrs. of ramification work ahead of me.
This one Ponderosa has full tufted out candles, and tons of backbudding. It's very established. And all it got last yr. was very heavy feeding, hence the long needles. I think my second one didn't do quite as well despite being in a pot 2 yrs longer is b/c it's in soil with broken down pumice and some sand too, I couldn't fertilize nearly as much as it retains way too much moisture. I'm going to repot it out of it's 3g. nursery container to a small box while not touching the roots. This spring, I'm just going to gently wash away the broken down substrate, situate the roots, and pot it up.