Acer palmatum dissectum 'Inaba shidare' will meet all your criterias on one condition, right before purchasing one (they are readily available, even at HD) you have to decide what form you want it to be in say 10-12 years.
They are easily trainable by selective (somewhat artistic) pruning in early spring and ocassional snap here and there during the growing season. Depending on what you want to see you should select its initial form and then just slightly improve it every year.
I have one trained (pruned) in a relatively narrow vertical tree with cascading branches all way down from 6' to the ground and another one only 3' tall so far, but about 4-5' wide.

Thank you both for the helpful replies. It sounds as if this will require a lot of pruning--an outdoor bonsai. I want it to stay about 3' and no more than 5' in diameter. Very slow growing.

Is there such a plant? I swear I have seen such things in other gardens. Have they all been pruned that way? I was hoping to cut back on maintenance....

Speaking of bonsai, I just went to mountainmaples.com to look up how big Red Dragon gets. That's one thats been on my wishlist for awhile as being very hardy and good color throughout the season.

I found that MM now has a New England division at Bonsai West! Check this out:

mountainmaples in Littleton MA

It sounds like its not necessarily bonsai related.

I also expect that the growth rate is going to be affected by the amount of sun/shade and soil/water.

That's a great website, Wendy. I like the feature in which you can enter your requirements--color, size, zone etc--and get some recommendations. The nursery in Littleton is not far from me so I will check them out. They also have the one that George recommended, tho not in stock at the moment. And I have learned that a "mushroom" shape is what I want. Thanks very much for the help.

yeah, I have Inabe Shidare, and I'm waiting for it to weep and look good. Mine was trained kinda tall and looks like a lollipop. This was taken in september 05 its first year here. Not very colorful at that time, but great in spring and fall. Its weeping a bit more now.

{{gwi:1071586}}

Pretty tree, Wendy. When does it turn purple? The ones sold by mountainmaples are all pruned to a tree shape, rather than the mushroom I'm hunting. But George says it is around so I'll keep hunting.

Ginny, I'm so glad you've asked this question, as I'm looking for something similar. Thanks everyone for your responses.

Wendy, I love the link to mountainmaples! Will they actually be selling stock out of Littleton?

I have a purple sandcherry that just isn't making it. It's more of a sad bush than a tree. This thread has been very helpful with ideas for replacements.

Judye

This is mine in November that year:

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I was riding by Bonsai West today so I had to stop in. Actually I thought of an errand nearby so that I could work it in to stop in!! The bonsai displays were absolutely incredible. I am not a bonsai fan at all, but I was very impressed.

The Mountain Maples selection seemed pretty good. Kinda expensive, but no shipping :-) $59, $89 and $198 seemed to be the 3 prices I saw. Just to have so much selection locally was very nice. They had a lot. I, of course, found one calling my name.

Ginny, today I made pictures of both of mine InSh and will try to post them either later tonight or tomorrow, but let me assure you that when you'll see it at the nursery you'll know immediately if it will be a 'tree' or a 'mushroom'.
In a first tree years InSh almost always show its character and nurseryman already did a major decision of what it will be in a future.
For the 'mushroom'-shape your future pruning tasks will be very minimal if any at all, 'tree'-form would require some creative work, but still manageable.

Both of my maples are fairly young, probably 5-6 years old, 3-4 years at the nursery and 2 years in a ground.
In full sun plus reflected light off the house,
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'Mushroom' form is usualy formed by removing single leader at the crotch, though sometimes leader just aborted naturaly or never develops (that is why you see more 'mushrooms' than 'trees'). Eventual (approximate) height of the 'mushroom' determined by the height where the leader was cut off.
Very open bright shade,
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In a fall both of them will have a same color, identical to this one.
15 years old Inaba Shidare from the neighbor's yard in a fall,

One more time, before you spend big bucks at the nursery, check HD or Lowes, at this time of the year they should still have them. At least mine does and prices are in $59-129 range depending on a size. In a fall they will be in stores again.
Good luck.

Very beautiful trees and photos, George and Wendy. Thanks for sharing these with us. And they well illustrate the difference between a vertical tree shape and a mushroom shape. One picture is worth a thousand words etc.

I will definitely check out my local HD but I am not usually thrilled with their offerings. There is definitely a difference in the merchandise among various branches of this store and others. But worth a look.

Wow! Thanks for all the pictures. What gorgeousness! And great info. I love the shape of the mushroom and that it makes very open bright shade.

Weston Nursery sells these for way more money than Mountain Maples!!

This morning I called the toll free number on the MM website to findout where in Littleton it is. They're on California time...so hope to hear back from them later. Anyone have the local info?

Thanks!!

I actually have a Japanese Maple that I've thought about removing from my yard. It's too big for the area that it lives in now - I actually feel bad for it's cramped living conditions. I need advice on how and when to transplant it. I've been in my house 2 years and been working on the landscape myself. A little help would be appreciated!! Please?

Jap maples fairly easy transplants at any time of the year, though I wouldn't do it in a heat of the high summer.
You'll do a favor to yourself if you postpond this till next year's early spring and move it while leafless.
Unlike other 'full size' maples, JM have a relatively compact root system, so if you dig a rootball at 1/2 (or even slightly less than that) of the tree spread it will be sufficient for successfull transplantation.