OK, I just found a potential tree for you! How about a Black Alder tree? I was researching Nitrogen Fixing trees and found this, then I thought about you :) http://advancedtree.com/tree_blackalder.htm "The Black Alder grows vigorously and has a central leader tendency. Its leaves remain dark, glossy green late into the fall. The Alder converts nitrogen from the air into its own fertilizer, producing a growth rate of up to 6 feet per year. With a total growth of 60ft by 20 to 24ft, it can be used as a screen or shade tree. (For Screening and windbreak plant trees 6 to 10 ft. apart.) The Black Alder needs plenty of moisture to get established and will grow in heavily compacted soil if a moderate amount of water is available. Alder will grow in extremely wet conditions." It grows in zones 4-7. I'm thinking of planting this in my side yard to replace a giant old Spruce that was uprooted during a Nor'Easter last month. I need some fast privacy and the soil is pure clay. 25 feet wide is perfect, and 60 ft. high isn't bad either. You will have a hard time finding something that fits your height requirement that doesn't require maintenance, so this seems to fit the bill best.

I would like to suggest that you quickly fire or otherwise cancel the guy who is going to remove the wall. Then STOP, as Mad Gallica suggests! Then there are just a couple of things to do while you wait for spring. First is to measure your lot and draw up a plot plan that you can use for testing designs. This isn't hard to do, if you have a measuring tape, a straight edged ruler, and some graph paper (use 4 squares to the inch, it works best). Basically you'd want to include all the existing trees and structures, the location of the driveway & walks, utilities and the septic system components. Make copies of the base plan and then get some colored pencils and try different arrangements for "blocking" masses of plants. This will really help you to figure out where you really need borders, how wide you want them to be, and how tall the plants should be. Selecting the plants should come much later in the process. At the same time, go get a copy of one or more of Gordon Hayward's books; The Welcoming Garden is a good one. It describes how to get from square one (where you are) to having a house in a garden. It's got lots of useful techniques for deciding things like placement and depth of borders, selecting a style you'll be happy with, and how to make your design complement the locale. These little "passtimes" might get you interested in gardening to an extent you can't even imagine at this point. If that happens, we'll be here - egging you on. And by the way, welcome to the forum! Nice to see someone who has a blank slate - so many possibilities ahead of you.

I agree with Rockman, a deciduous plant often works as well as an evergreen for privacy and they're usually much more rapid growers. If you want a few hundred privet, they crop up all over my yard. No kidding, on my 1/3 acre lot, there must be 300 privet seedlings at any given moment. I don't remember seeing privet on the invasives list, but I'd have to say they're one of the worst offenders here on Cape Cod; I spend a lot of time pulling and digging them. Of course, in CT you might not have that problem. They sure are fast growing, reliable, and inexpensive (as in I'd pay you to to come pull them up). Also, they have lovely fall coloring - not bright red, but deep mysterious purple-green. And, the birds obviously love the seeds and the cover they provide. I have a Lindera benzoin (spice bush) that reached its 6' size very quickly from a rooted twig; they are native, have fragrant foliage (so are probably deer resistant) and have tiny yellow flowers in March. Birds, including American Robin, Northern Bobwhite, Gray Catbird, Eastern Kingbird, and Great Crested Flycatcher, eat the drupes. A row of native bayberry might be really nice, too; large swaths of them were recently planted on the campus where I work, and they've reached 6' quickly, forming beautiful banks of nearly evergreen foliage. I've got some in my garden that are a bit of a pest because they're sited too close to perennials - they spread, which might be good for your situation. I envy you the space you have, but not the deer problem.

How's the drainage? I have clay soils and grow some 100+ different species of trees and shrubs. Never fertilize, do not mulch. Bought 10 acres of a place with about 4 trees. Something like Chionanthus virginicus grows fine, is deer resistant, but needs well drained land. It absolutely needs sloping ground if you have clay. The shape is a mound about 15 ft. tall (after about 10 years from a sprig). Native evergreen Hollies (like Ilex opaca) make a decent screen after just a few years. If you want to put up a trellis, you can hide anything in 3 years with Aristolochia durior (macrophylla is a synonym). Doesn't spread all over, thrives in shade that is not to deep. If your idea is to plant it and forget it, forget it. Even the best situated, native or foreign plant needs a pruning to eliminate crossing or dead branches. Pruning to shape is also often needed. Spending every weekend is not required, but 10 hours/tree/year should be expected. (Pruning, weeding etc.)