i have a japanese maple called polymorphum. unlike my other maple trees, the leaves of polymorphum are tiny, and bushy... to me it's unattractive and too bushy that aphids bred on it. last summer heat scrotched the leaves... so i pulled out all those brown, ugly leaves out from this tree so that new leaves can grow. it's almost in the middle of autumn/winter - and the leaves are still green. the colors hasn't changed yet. what could be wrong? i'm so desperate to see the atunmn color of this tree, but never have the luck to see it for the past 2 years since i always pulled out all those brownish leaves out. if i don't pull them out - the leaves will turn brown and die away. P.S.. i've been doing a search on polymorphum but there's none - is that the tree's real name?
As regards Acer palmatum ssp. palmatum, in the 19th century confusion of the species names was considerable as various dendrologists, taxonomists, and botanists had given this species various names, including, but not limited to: A. polymorphum var. palmatum; A. japonicum var. polymorphum; A. polymorphum var. thunbergii; A. polymorphum (which was even broken down into six varieties). Pax (1885) finally brought order out of chaos by recognizing the name Acer palmatum Thunberg ex Murray as the correct one based on priority and nomenclatural typification, thus bringing the double use of A. polymorphum and A. palmatum to an end. Van Gelderen et al., Maples of the World (Timber Press 1994). It is more than surprising that you should come across a tree labeled such as there is no registered cultivar with that name to my knowledge. It sounds as though you have a bushy, small-leaved variety of Acer palmatum, which should show fall color under normal circumstances. However, yours has suffered under the heat these last two years, and from my limited experience, scorching of the leaves severely curtails the typical fall display. As far as aphids and maples, I have noticed that they are worse in warm to hot weather, but others may have different observations. This year it has been an usually warm spring, so aphids were much more of a problem in my collection. The problem is the worst on tender spring growth, so you could be diligent and hose down the leaves in the earliest morning hours and smash the remaining aphids with your fingers. Is there any way that you can post some photographs at some point and note the approximate dimensions of the leaf and petiole (the part that attaches the leaf to the branch)? One of our members may recognize it if it is a grafted, named cultivar, or else it could be a seedling of any A. palmatum, which can be just as lovely. Even if you post a winter photograph of the tree, someone can give you ideas on how to prune it to open it up so that it is not as bushy and unattractive to you. Also are your maples planted in pots or in the ground? Are they planted in full sun or in some shade?
hi laurie - thanks for replying, below are photos taken 1 year ago... the leaves are small, simple and dark green during summer - the tree doesn't even look like the label photo that come with it... maybe it's still young... see how the branches go upright like a "U" shape... i want it to go more of a T shape or an umbrella shape. i probably find the label photo of this tree tomorrow and would take more pics of this tree tomorrow morning. the second pic is next to another maple called sangokaku... i find sangokaku more beautiful than this polymorphum tree. all my maple trees are potted because i am renting. they are usually exposed to morning sun, and i would move the pots to the carport for shade.
I realise this is an old thread but just in case you're still interested theres this: http://www.flemings.com.au/ornamental_details.asp?CULT_ID=POLYPAL
