Moss growing on your roof or in your gutters can cause a damage that leads to costly clogged gutters and leaks. Moss is a small, green plant that grows in damp areas. Mosses don’t have seeds but reproduce mainly by spreading their tiny spores. You will find it more likely in shady and moistly surfaces such is roof or gutters. It holds moisture against the roof, which can lead to rot and deterioration of the shingles or other materials. Also it may attract nesting birds and insects, which are likely to cause further damage to the roof and gutter system.