DaveG
Mame
I've had the idea knocking around in my head for a while that it might be possible to accelerate trunk, branch, and root thickening of dwarf varieties of some trees by grafting normal stock to the ends of branches and roots. It may depend on the specific cause of dwarfism in the tree in question, of course. I've spent some time looking for information on this idea and that's turned up nothing so far. I was wondering if anyone here has tried this or something similar.
The basic idea is to let our dwarf tree grow for a few years at its normal rate, which yes, can be painfully slow, then graft a non-dwarf scion to the tip of whatever we desire to thicken up. The graft should be strategically placed beyond the intended point of a chop that's to be performed in the future, so that the non-dwarf part is later removed, leaving us with a nice thick trunk on a very slow-growing tree with short internode spacing. This could be done progressively higher so as to obtain a nice taper and then finally stopped when our tree has the intended trunk shape and thickness.
Also, I see no reason to remove the tree's other dwarf branches as we go, as they will still provide the tree with energy, help it thicken, and can possibly be prepared for further grafts higher up. Depending on how the tree distributes growth while it's grafted, it seems like it would even be possible to start shaping lower branches before all of the grafts are removed.
I believe, using this technique, it might even be possible to take some dwarf varieties to a "terminal size", where they effectively just don't want to grow vertically anymore once the non-dwarf tissue is removed, effectively taking on some growth characteristics of very tall specimens of non-dwarf varieties. But it will take years to determine if this is the case.
I'm presently preparing to try this on a 5-year-old dwarf trident maple I currently own, which I purchased as a "Miyasama Yatsubusa", but I believe should correctly be called "Miyasama Kaede Yatsubusa". I have some trident maple seeds in the fridge that I'm preparing to try to approach graft to the branches of it as soon as the seedlings are old enough. I also want to try it with several varieties of Chinese elm (Hokkaido, Cantlin, Cantlin Contorted), but I currently lack the dwarf specimens I intend to try it with and probably won't have them for at least a few more months.
The basic idea is to let our dwarf tree grow for a few years at its normal rate, which yes, can be painfully slow, then graft a non-dwarf scion to the tip of whatever we desire to thicken up. The graft should be strategically placed beyond the intended point of a chop that's to be performed in the future, so that the non-dwarf part is later removed, leaving us with a nice thick trunk on a very slow-growing tree with short internode spacing. This could be done progressively higher so as to obtain a nice taper and then finally stopped when our tree has the intended trunk shape and thickness.
Also, I see no reason to remove the tree's other dwarf branches as we go, as they will still provide the tree with energy, help it thicken, and can possibly be prepared for further grafts higher up. Depending on how the tree distributes growth while it's grafted, it seems like it would even be possible to start shaping lower branches before all of the grafts are removed.
I believe, using this technique, it might even be possible to take some dwarf varieties to a "terminal size", where they effectively just don't want to grow vertically anymore once the non-dwarf tissue is removed, effectively taking on some growth characteristics of very tall specimens of non-dwarf varieties. But it will take years to determine if this is the case.
I'm presently preparing to try this on a 5-year-old dwarf trident maple I currently own, which I purchased as a "Miyasama Yatsubusa", but I believe should correctly be called "Miyasama Kaede Yatsubusa". I have some trident maple seeds in the fridge that I'm preparing to try to approach graft to the branches of it as soon as the seedlings are old enough. I also want to try it with several varieties of Chinese elm (Hokkaido, Cantlin, Cantlin Contorted), but I currently lack the dwarf specimens I intend to try it with and probably won't have them for at least a few more months.