Thuja plicata 'green giant' is a variety of western red cedar that's becoming much more available due to its usefulness. It is a large fast growing evergreen similar in appearance to its cousin Thuja occidentallis (Northern White Cedar or arborvitae), but has a greater tolerance for shade and grows faster. It seems to be rapidly replacing Canadian Hemlock due to the latter's problem with Wooly Aldegid. You should be able to get these in large sizes (10'-12') without too much difficulty if the wallet allows. Good luck, changes like that in our home lives are tough to take. I have to sympathize on both sides as I would really like to throw a second floor on my tiny house. I'm sure my neighbors to the rear (with the pool) would be thrilled. I should worry about landscaping the place first, though.

I would suggest some sort of vine to grow on that nice upper portion of the fence, such as Solanum jasminoides (potato vine), or maybe a Clematis armandii. Hardenbergia violaceae (lilac vine) is also gorgeous and evergreen, but I am not sure it would have the habit of going up and then spreading out as the others do. There are many vines that would cost less than a group of trees, be evergreen and easy care, and leave you space along the fence for an ornamental border if you want. Check in with a local nursery regarding light exposure. That looks like a pretty hot space, and I vote for the potato vine. Grows like crazy. HTH. -perL

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.

Hi Eric, You mentioning wanting 'green giant' but it gets too wide. Green giant is actually thuja plicata 'green giant' but how about a variety of thuja occidentalis? Perhaps thuja occidentalis 'brandon' (brandon cedar). They grow to about 15 feet high (taller with age) and perhaps 4 feet wide. The brandon variety is extremely winter resistant even here in zone 3 but you might also want to check out other types such as 'rushmore', 'smargd', 'pyramidalis', etc. Just search on the internet for "thuja occidentalis brandon", "thuja occidentalis smargd", etc. 'brandon' and 'pyramidalis' are fairly quick growing, as far as cedars grow, but unfortunately you are still looking at maybe a foot in height per year. Anything that is quicker growing than that, say 3 feet per year, probably wouldn't stop at just 15 feet high. They would do well in part shade. They would have to be watered regularly until established (no different than any tree or shrub) but are somewhat drought tolerant once established. Glen