Question
Hi,
I want to alternate maples and norway spruce to block out the view behind it. I was thinking of alternating norway spruce appx. 9 ft apart in a stagger and then put 2 maples in front for color so it isn't a big green screen. I want to see the maple trees and get major shade from direct bright sun into my house/deck.. What spacing do I need for this? Thank you

Answer
Hope you have a big site.  Most folks who ask me landscape questions, live in an urban setting.  Maybe you have a 1/2 acre or so to work with, as Norway Spruce (Picea abies)  get HUGE!  60 feet tall x 25 feet wide:

http://www.arborday.org/trees/treeguide/TreeDetail.cfm?ID=37\

Spruce spacing should be no closer than 15 feet for a dense hedge, in a few short years.

So do the Maples (Red/Silver/Sugar):

http://www.arborday.org/trees/treeguide/TreeList.cfm?SearchText=maple

Maple spacing should be no closer than 15 feet. Some maple roots are invasive (Norway & Silvers), so don抰 try to grow lawn under them, or plant them over a septic field, or you抣l give yourself headaches in a few short years.

The 搇ittle?maples are the Amur, Tatarian, & Japanese varieties.
Spacing can get as close as 5-10 feet apart, with just as brilliant a fall display.

Its about patience, too.  Plant them too close, and you'll have to heavily prune or take some out, later.  Hope it helps.  ~Marc