Where not to install a metal roof

A dozen years ago, I had a metal roof installed on my house. The sheet metal has 1 inch high ridges each foot. The sheets are installed in the North -South direction. West of the house are a bunch of Douglas firs and other needle trees. The prevailing winds are from the West, so lots of needles are blown on the roof. As the needle have resin in them, they stick and accumulate on the sheet metal ridges. So far, I have vacuum-cleaned the needles every year. But I am getting too old for this rigmarole. I notice now that the paint has disappeared in places and that the zinc coating shows up. So I am stuck with repainting the roof. Another part of the roof (with the same slope) has sheet metal ridges installed in the East-West direction and has absolutely no problem. The local contractor should have anticipated this problem. I am only posting this so potential consumers beware of this problem.