Today I dashed off to Piney Woods Church Road mid-afternoon, having returned from one hike (Line Creek Preserve in Peachtree City; photos from that walk will be posted tomorrow) and being about to leave for another one (Boundary Waters Park in Douglasville, where I hiked sans camera). I took few photographs; one feature that caught my eye was a Christmas fern (Polystichum acrostichoides) sporophyte frond covered with tiny brown dots, called sori (singular: sorus), which are clusters of spore-bearing structures called sporangia. Each sprangium, in turn, contains countless dust-like spores. Basically, there is a whole lot of reproduction going on here. No sex, though — that is reserved for a separate generation of fern plants, called gametophytes. Alternation of generations (from gametophyte to sporophyte and back to gametophyte) is characteristic of ferns, mosses, and their ilk.
