Sherwin,

I recommended immediate pruning because "shading out" is what kills off a slower
growing scion when the rootstock begins to put out its own, more vigorous growth.
Immediate first aid is to make sure the scion gets as much sun as possible.

Nothing attributable to the means of propagation controls the growth rate of
A.shirwasawanum whether grafted or on its own roots. It is just naturally a slow growing
shrub. And you are correct, there are no growth controlling rootstocks for Japanese
maples.

--beeky

sherwindu wrote:

wrote:

This situation is not uncommon for any grafted plant. The solution, as Sherwin
described, is to prune off the growth from the rootstock. I would suggest removing
about 1/2 of the A.palmatum immediately. Just pick enough branches to reduce the
leaf area by 1/2. Try to prune branches that may be shading the A.shirwasawanum.
Next spring when you are sure the A.shirwasawanum has survived prune off the
remaining A.palmatum.

If this tree behaves similarly to a fruit tree, you should do your pruning before
any of
the buds open up. That would be early in the Spring.



I have to disagree with Sherwin about preventing the scion from producing its own
roots. For this type of plant it does not matter. For some things, dwarf fruit
trees for example, the dwarfing is produced by the rootstock. If the scion roots
the dwarfing influence is lost and the tree will develop into a full sided adult
instead of a dwarf. For your plant the rootstock is nothing but a root system. If
the scion also roots you just have more roots, a good thing.

Right. I thought this plant was structured like a grafted fruit tree. I am a bit
curious what
controls the dwarfing of this variety. It seems like you cannot mix and match root
systems
to get the size of tree you want.

Sherwin