I think the bold feeling of Ponderosa looks great on big trees. On smaller ones, I’m not so enamored. So for 20 years I’ve explored, like others, grafting Japanese Black Pine onto Ponderosa Pine.
To start with, the scions don’t take well. I rarely get better than 50% take, usually it’s closer to 30%. Whereas it is possible to get 100% take with JBP on JBP. Talking with others confirms that the meager take on this match is a common one.
However once took, the scions flourish. The bark is a near match. And the decandling technique is identical to JBP.
Grafted Pondies are stronger, which results in more even candle strength. Here’s a JBP grafted Pondy, 10” high, from two scions about 12 years ago. This is before decandling. With last year’s needles about 3/4”.
I cut the candles on these grafted trees later than normal JBP, to control the greater energy. Usually only a few days later.
After 20 years I would have expected to see the same energy problems we see on older JBP, such as low branches getting weak. Especially given the age of these collected Pondies, which are much older than any available JBP. In a few years I’ll report back to see if that trend continues.
The overall impression is: JBP on Pondy is stronger than JBP on its own roots.
This strength is translated visually: JBP on Pondy, left, JBP on JBP, right. The needles are thicker and the shoots are a bit fatter. That is one negative I’ve found. (The color difference here is a specimen difference and not a graft commonality.)
They look bolder, which may be a negative on a small scale but fun on a medium and larger scale. They are stronger, which helps to even out decandling. And you can bring a very small Pondy trunk into the frame of bonsai—even into shohin—with a graft.
In all, it’s been a fun time maintaining these. I only wish I’d grafted more of them!