We live in Portland, Oregon, and have a composite roof in good shape.

Moss appears on the roof each year about this time.

I know that I could go up on the roof several times each winter and spread poison to kill the moss, but this is not something that I want to do, for obvious reasons.

Do zinc-coated strips of metal work?

If so, would you have to have a strip of metal along the entire ridge of the roof, plus at the top of the sections that have no ridge to them?

The roof has a moderate pitch, and is divided into four sections (back of house, garage, front of house and porch overhang).

If zinc does not work, does anything work?

Thanks.

Paul