Hm. I'm not sure I managed to get everything you wanted in one plant, but here goes...all of these grow easily in the Bay Area and should do well to the north of here as well.

My first thoughts were Leucadendron argenteum, silver tree--a drought-tolerant South African native, really stunning long silver leaves, fast-growing, very slender. Or Fremontodendron californicum--California native, super-fast, maple-like leaves, no summer water, eye-catching yellow flowers, easily pruned to fit your space. Only thing is I'm not sure how much shade either of those can tolerate.

Thuja "Green Giant" also grows REALLY fast (up to 3ft/year), but unlike the Fremontodendron it's long-lived and takes a little shade. Can get very tall (50ft or more?) and I don't think it would be very happy in a drought. I also hear it tends to brown a little in winter, although it's evergreen.

Italian cypress (cupressus sempervirens) will take a little shade and some drought, and it's very narrow and columnar (only 3-5ft wide but up to 40ft tall). Might not be the fastest grower, though, I don't have any information about that.

Deodar cedars (cedrus deodara) will take considerable drought, a little shade and they grow relatively quickly, but they may eventually hit 60-80ft. They usually require about a 30ft. circle, but if you cut back the candles in the spring you can keep them narrower.

There are probably a lot of eucalyptus that fit your requirements as well. They have a bad reputation because of the invasive eucalyptus globulus, but there are many non-invasive ones that grow fast, tolerate drought and might tolerate some shade. I don't know too much about them, though.

Mlevie while perhaps trying to be helpful has given you suggestions that may have no basis with your situation. I'd suggest that you look up the list of fast growing trees as listed in Sunset Western Garden Book, and cross reference these with the shade and drought tolerant plant lists. Do your own research and then look at them at a good local nursery to decide if you like the individual plants. It would also help to know what town you are in or your Sunset Climate Zone, as these are more accurate for your actual conditions than a generic USDA zone 9 designation.

I mean come on, suggesting Leucadendron argenteum as an easy care fast growing tree for anywhere outside of the mild coast is not a good suggestion, and Deodar Cedars as a small 15 foot tree? Neither is a particularly useful suggestion for you question.

I've seen Xylosma used successfully in the conditions you mention. It may get wider than you want, but is easily pruned to keep it narrower, I've seen it espaliered successfully. It's pretty easily found in most nurseries.

Here is a link that might be useful: xylosma

Do they need to be at least 15' tall, or no more than 15' tall, or ? At that height, a large shrub rather than a tree will fit the bill nicely, give better screening, and may be less work. There are quite a few California native shrubs that could work. Sounds like you are looking for screening rather than shade since the area is in partial shade. Very narrow you are looking at something like Skyrocket Juniper, or you are looking at regular pruning (maintenance). How narrow? More info would help.

Bahia has suggested you look up the fast-growing trees list in the Sunset Western Garden Book. Perhaps he/she should do that him/herself, because I'm looking at the latest edition and there is no such list.

I've seen lists of fast-growing shade trees, but you have to be very careful. Many trees and shrubs that grow fast will either (a) become invasive, (b) have very brittle wood, (c) are extremely susceptible to pests and disease. In horticulture as in life, there's not really any free lunch.

I apologize, I shouldn't be so argumentative. It's not a contest for who has the best suggestions.

I do like davissue's suggestion of xylosma--Sunset Western Garden says it only grows to 8-10 ft., which just goes to show you can't believe everything you read.

Have you considered a fruiting tree? A fig like black mission would certainly fit the bill. There's a movement to make more landscaping edible. Check out foodnotlawns.com.

Bambusa multiplex ÂAlphonse KarrÂ
GOLD-STRIPE BAMBOO
Bambusa oldhamii GIANT TIMBER BAMBOO
Calocedrus decurrens ÂFastigiataÂ
COLUMNAR INCENSE CEDAR
Cupressus forbesii ÂGreenleeÂs Blue RocketÂ
BLUE ROCKET TECATE CYPRESS
Juniperus chinensis ÂBlue Point BLUE POINT JUNIPER
Juniperus chinensis ÂColumnaris COLUMN JUNIPER
Juniperus chinensis ÂSpartan SPARTAN JUNIPER
Juniperus communis ÂStricta IRISH JUNIPER
Juniperus scopulorum ÂSkyrocket SKYROCKET JUNIPER
Pittosporum crassifolium KARO
Pittosporum tenuifolium (esp. ÂSilver SheenÂ) KOHUHU
Podocarpus macrophyllus ÂMaki DWARF YEW PINE
Rhamnus alaternus ÂJohn Edwards ITALIAN BUCKTHORN

Joe

Beware when folks send these lists. A gardener planted a couple of Italian Buckthorns in my yard almost a year ago after I asked for "fast growing trees" and they've grown no more than one inch. Perhaps the type of soil has something to do with it.

If you have a way to contain the shoots, bamboo. If not, Pittosporum tenuifolium.

Rhus integrifolia, LEMONAID BERRY an evergreen California native which meets all your criteria. Easily reaches twenty feet and makes a very good screen. I have them for more than 15 years and have never noticed any flowers or fruit. They should be available from native plant nurseries. Mine have never been watered, do not mind Calistoga hot summers and have never had a disease or pest. Al

I'll add my old favorites, Azara microphylla or dentata.

Lyonothamnus, a CA native, can reach 30', but has a narrow spread (10-20')

The Pittisporums, as suggested above, are probably one of the fastest growing trees/shrubs for a narrow space.

As mtrimble has noted, most trees/shrubs are slow in the beginning. It often takes at least a year for the roots to get established before the plant will put on any real growth.

wanda

Improve the soil and water the first couple of years, and you'll get better results. I've got a variegated rhamnus that went from 12" to over 12' in less than 4 years.

Note that most trees, even if they gain the height you want, still won't have much width at the tops until maturity. You might want to intermix them with standards (shrubs trained as trees).

Frankly, you might get a better solution if you simply install a privacy screen or trellis, assuming codes will allow it, then grow a vine up it.

Moringa Oleifera (Drumstick plant) will be a good choice.It will grow to a height of 15 to 20 feet in about 3 years.