Weird building/roof question?

[Derek Reese 29]

So I have a 2 story garage/shed that is not attached to my house whose layout is such that the sides of the roof face due north and due south. This shed is surrounded by large maple trees that almost completely shade it on the north side. On that north side of the roof there is a fair amount of moss growing. As far as I know the roof is not that old. Is there a way to get rid of the moss (besides cutting some of the trees and allowing more light in, which is in the works). I had heard something about putting copper pipe up there to change the pH of the rainwater hitting it? Forgot to grab a picture this morning, but will try to remedy that soon.

 

[35-acre]

There is a spray that you can get that attaches to a hose and it kills that stuff. I got it at Home Depot. It's a "spray and forget" kind of thing:
. https://www.homedepot.com/p/Spray-F...ary-Roof-Cleaner-Hose-End-SFRCHEQ06/312628427
This works to avoid this kind of thing:


The idea of putting a strip of copper up under the top-most shingle leaving a little hanging below the shingle for rain to hit is how roofs used to be built to accommodate this issue as well. I don't know if it will cure an existing issue if you've already got mold growing.

 

[Troubles Trees]

Back when I was a carpenter we installed zinc strips at the peak under the cap shingles for just this purpose.

 

[Troubles Trees]

I don't remember the exact product we used back then but this is the same stuff.

Preventing Roof Moss with Zinc Strips

In this video, This Old House general contractor Tom Silva shares tips for keeping a roof free of moss and mold

www.thisoldhouse.com