Copyright 2016 by Mario Vaden
The coast redwood below may be a good opportunity to spend a moment talking about stuff like moss and lichens that grow on redwood trunks, or the lack thereof. Have you ever seen my photos showing the trunk and bark of the Del Norte Titan? There's very little moss on it, but plenty of lichen which often looks white-grey, grey-silver, blue-green and other variations of color. The DNT is over 2000 years old and even at that age has minimal moss. In a lot of groves, there's barely any moss on many of the coast redwood trunks. Take a moment ot look at my photo for the coast redwood Melkor. There's hardly any moss or lichen on that one. But if we pay close attention while hiking, it should be evident that moss is more scarce than lichen on many of the coast redwood trunks passed along the trail.
The species that generally have the most moss, even on middle age trunks, are Douglas fir, and especially western hemlock and Sitka spruce. When you approach Jedediah Smith park from the west sometime, before you reach the gate, there are scores of Sitka spruce laden with mossy branch stubs. If you hike James Irvine trail in Prairie Creek park, most mossy trunks should be hemlock or spruce. Not always, but usually. Bark of different evergreen species differ for chemical substances they produce. The concentration can vary with bark age, exposure to sunlight and moisture, etc.. That's why there are trends but still some variation.
The presence, absence or combination of mosses and lichens in the redwood forest adds to the tapestry of color we can enjoy. Algae and other stuff can be present too.