Question
I have a low spreading laceleaf japanese maple that I believe was grafted onto a rootstock from a different species of japanese maple, possibly an Osakazuki. From the base of the tree is sprouting an entirely different type of leaf, similar to an Osakazuki maple I have. Should I allow this new growth to continue or should I treat it as a waterspout and prune it off? Potentially the two trees could look quite beautiful together but I'm concerned about competition and the overall health of the rootstock and ability to feed both trees. Perhaps hard pruning of the upstart tree would keep new growth to tolerable and attractive limits?

Answer
Hi Paul,
Thanx for your question.  Hybrid trees are often grafted onto stronger rootstock.  If you allow the root stock to grow its suckers your original plant will disappear.  Prune all the ancillary growth and make sure the knob of the rootstock isn't buried in dirt.  I hope this helps.
Tom