This summer, as part of a larger project, I found myself compiling a list of mosses on a private property in Taghkanic. Mosses can be found on lawns, rocks, fallen logs and rotting wood, the shaded forest floor, and even on tree bark. Many mosses do not have well-established common names, which would be so much easier to remember than their scientific names. My own photographs are supplemented with some stunning close-up images from the Digital Atlas of Mosses by Jerry Jenkins and Sue Williams.
I thank Tom Phillips for confirming and correcting some of my moss identifications. Any remaining errors in this post are mine alone. Mosses of the genus Polytrichum are also called haircap mosses, because of the hairy cap that protects the young spore capsules.
Two of our most common species found on woodland trails, in lawns, and on rocks are Common Haircap Moss P. They can be distinguished in the field by the shape of their angular spore capsules: Common Haircap Moss, which is pictured here, has a constriction at the base of a short, box-like capsule, which separates it from a disk at the top of the stalk, while Oak Haircap Moss has a more elongated capsule without the constriction.
Haircap Mosses Polytrichum spp. Both are examples of mosses with an upright growth form acrocarp mosses. The leaves of Oak Haircap Moss are narrow, stiff, and resistant to desiccation, which means they keep their shape even in dry conditions. In contrast, the leaves of Wavy Starburst Moss are broader, less resistant to desiccation, and have a unique wavy surface when hydrated.
As shown in the next image, they quickly curl up when dry. Next are two very different images of Wavy Starburst Moss Atrichum undulatum Group : on the left, a patch with rather dry leaves of the haploid female plants, bearing orange-stalked sporophytes. A sporophyte is the diploid phase of a moss plant that grows on top of the haploid female plant and produces spores.
