Around here, moss grows overnight. It makes everything very slippery. My condo association recently installed Gripstrips on our wooden walkways that get slippery in the winter. They have reduced the number of people falling to ZERO this winter! We place them two feet apart, and it’s enough to stop a skid before it becomes a fall. They are the best product ever. (I’ve used chickenwire stapled down (painful), and composition roof tiles (ugly). GripStrips are attractive and they work!! GREAT PRODUCT!!