Magnolias usually have shallow roots but the ones close to the surface tend to be finer feeders and those are what might reach the liner. However I don't think they would actually uplift one unless the tree is quite mature and/or the tree heaves out of the ground. I was looking at some lists and there doesn't seem to be many choices for evergreens per you specifications that would be hardy in the tri-state area. Ilex crenata (japanese holly) doesn't seem to appear to be on the toxic list (it is normally non-berry producing). Pyracantha is also not on the list (the berries are also eaten by birds - although usually after they have used up tastier ones). Camellias (there are cold hardy ones) also don't appear on the list. And as conifers, spruces and junipers aren't on the toxic lists.

Ah yes, Ken. That was me. (Here's the old thread.) Although it's more like .25 acres of what I own, even though my front yard opens out into the woods. I'm also the nutty guy trying to go all native with mini meadows, rain gardens, ponds, and the like (I'm getting there). Anyhow, I'm not in love with the sweetbay, and I'd just as soon get rid of it but my wife constantly reminds me I paid $180 for it last fall. Since I shouldn't expect anything glorious for a few years, why not move it one more time the front of the house and put something in there that I really like. That is the issue. I actually tagged a 3" cal black gum last year at the nursery and they just called me to tell me it's been dug out and do I still want it. I know people didn't like my placement of the black birch and how there would be 3 canopy trees in a 20' x 25' area, but I'm really, really thinking about going for it. I would put it where the sweetbay is now. Here's my backyard as of yesterday if anyone wants to weigh in: Again, I'm not looking for perfectly-formed trees here. My idea is the three of them to form a canopy. My greatest enjoyment is sitting on my patio and watching the birds and critters and I've always wanted a black gum. Thoughts?

'Henry Hicks' is available from Fairweather Gardens in Greenwich. Any tree will shed fruit/leaves including magnolias. This magnolia doesn't grow very dense, you might consider some of the evergreen myricas. Sam Here is a link that might be useful: Fairweather Gardens

Bumping up this good question since there has not been a reply.