[RWebb]

"Trees, any trees, any amount of trees and type of trees will do nothing for sound decay."

- Wow - I rarely see such completely incorrect statements. I simply cannot understand why people post this stuff when they obviously don't know which end is up.

Trees will significantly attenuate sound and this is well published in the scientific literature. How much depends on foliage characteristics.

You might try Doug. Fir - they will grow very quickly around here and have rel. dense, persistent leaves (evergreen). You can put something you like better behind them. Plant another row in a few years -- When the originals get too tall, you can cut them and sell them or just rely on the ones behind. You may have some shading issues eventually - if so, cut the tallest ones down.

You can also use slower growing but more ornate trees in the second or 3rd rows you plant.

D Fir is a very fast grwoing tree in the PNW and into SFO as well.