Platismatia Stenophylla, Ribbon Rag Lichen

Day 105: The Pacific Northwest has its share of Rag Lichens, so-called because they have the feel of a damp dishrag when touched. Many of the species are quite "leafy," and can often be found growing on old cedar fences as well as tree branches. At least two are more "lacy" in appearance: Platismatia stenophylla (above) and P. herrei. Both of them form loose clusters which frequently become dislodged during wind events. I've learned to differentiate them on sight, but in the early days of my lichen adventures, I had to put them under the microscope to check for isidia/soredia (reproductive structures), present in P. herrei but absent in P. stenophylla.

Platismatia Duo

Day 55: If I'd been conducting a lichen walk, I couldn't have asked for a better demonstration of two species of Rag Lichen. A piece of Ribbon Rag (Platismatia stenophylla) had dropped on the trail right beside a similarly-sized hunk of Ragbag (P. glauca), forming a textbook comparison without the slightest rearrangment by me. At first glance, P. stenophylla could be taken for P. herrei (Tattered Rag) which also occurs in the Park, but herrei exhibits soredia and isidia (reproductive structures) on its lobes. As a general rule, Platismatias tend to have a soft, limp feel when handled, hence the word "rag" in so many of their common names. In particular, Platismatia glauca takes on a pink tinge as it ages, making it look even more like a soppy old dishrag.

Platismatia Stenophylla, Ribbon Rag Lichen

Day 163: Several times as I've walked the loop trail at Tahoma Woods, this beautiful specimen has caught my eye, but by the time I've returned home, I've invariably forgotten about it. Yesterday during my "Intro to Mount Rainier's Vascular Plants" walk, one of my companions noticed it and put me on the spot for an identification. Caught out, I tucked a small sample in my pocket for analysis, but had left the camera in the car, the better to keep a good pace for the group. Today I returned to the site and discovered to my delight that in the short span of a few rainy hours, the lichen's foliose portions had not only reconstituted but had "bloomed" with apothecia.

The Platismatias are known as "rag lichens," and most are very soft and floppy. Platismatia stenophylla is no exception. The margins of its lobes tend to curl inward on themselves, forming channels. Pick one up, and you'll understand their common name. They are as limp as a wet dishrag. This species in particular forms graceful mounds such as the one shown here. It did require analysis under the microscope to determine that it was not the similar Platismatia herrei, but no isidia or soredia were present, confirming that it was indeed Ribbon Rag, and a new addition to my lichen research project photo files.