So a bit of exploring today led me to a new lichen for the yard list — and since this is one I know well, I'm a little surprised that I haven't noticed it before. The grey-green lichen to the right of my thumbnail is Diploicia canescens. As you can tell from my nearby thumb, the few colonies I've found so far are pretty small; this is one of the larger ones, which probably means that these are relatively new colonists in our garden. Like the bright yellow-orange Xanthoria parietina colonies around it (see my earlier post about those), this species can tolerate quite high levels of nitrogen pollution, which is a good thing considering all of the surrounding farm fields!
Up close, you can see some of the key features of this lichen. Its color is a very pale grey-green. The lichen's lobes are convex (that is, they curve towards the branch below it) and get wider towards the tips. Unlike the neighboring Xanthoria parietina, it seldom has apothecia (the structures that carry spores). Instead, it clones itself, bundling up small numbers of algal and fungal cells (the building blocks of every lichen) in structures that look a bit like pale, yellowish flour sprinkled on the middle of the lichen. These structures break off in wind and rain, or when an animal walks across them. Now that I've been looking a bit harder, I also found some on the brick wall of our garage. How did I miss it for all of these months?!
Who knew they have different ways of reproducing.
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