FredL

Hi BG, My feel for Mimosas is that they not only can but should stay outside in the Winter. Over here to the East in Arkansas, we see them very frequently by the roadside where they have gone native. They are maintaining their population here and actually seem to be extending it fairly rapidly. They are pretty in bloom but, as you point out, do not seem to be a very long lived species. From what I've seen in the bonsai books and magazines, lots of atypical species of bushes and vines are given the bonsai treatment in Japan and alot of very appealing and unusual examples are created. I don't see anything wrong with going with Mimosa. It it were me, I think I'd try slanting style, which seems to minimize the distraction of the big compound leaves of Mimosa and maximize the impact of the big showy flowers. I hadn't really thought to try Mimosa here; I'm doing enough off-beat things already!

As for Elms, we have alot of Winged Elms (Ulmus alata) over here that can be collected by the roadside. I picked up 3 about 18 months ago and have found that they adapt to pots very quickly and easily. I've been reading that they are excellent subjects for bonsai training. I'm not sure whether you have these trees as far West as you are, but, if you do, I'd recommend them highly. I have found that collecting natives is really fun and that you can quickly acquire a good assortment of material this way at little expense. It also pretty much guarantees that whatever you have will be well adapted to your climate. You might look around where you live for maples, hornbeams, hawthorns Crab Apples Hackberries and other natives or ornamentals that have reproduced themselves by the roadside or in peoples yards or woodlots. You will probably be surprized at what you see once you start to notice what's available.

Good luck, Fred