Everything you wanted to know about mosses in a free ebook, written in a style understandable by laypeople: Bryophyte Ecology by Janice Glime et al. I’m especially enjoying the chapters about the other organisms that live in mosses (tardigrades! slime molds!) and bryophyte phenology. Maybe it’s more than you really want to know about mosses, but hey, it’s a free book by a working scientist about a really cool taxon of organisms.