Zombie Season

Day 3: Zombie season is at hand! Or maybe that should be "at fingernails." They're reaching up from the forest floor, from stumps, from rock crevices and logs. They're coming to get you, and they want to eat your brains! Yes, lichens of all sorts are celebrating the return of cool, wet weather, and Peltigera membranacea is no exception. One of the "pelt" lichens, its fruiting bodies (apothecia) look suspiciously like the tips of zombie fingers groping for an ankle from beyond the grave. Will you be dragged into their lair this Hallowe'en? Mind your step and don't go out after dark! They're waiting, waiting, waiting...

Peltigera Britannica

Day 109: Any of my regular readers will vouch for the fact that I love lichens. In fact, I refer to them as the "wildflowers of winter" because so many of them come into fruit during the cold months of the year. Peltigera britannica is an example. If you look closely at the photos, you will see that the green surface of its lobes are flecked with tiny black dots. These are its cephalodia, small gall-like propagules which are at this point composed of cyanobacteria. Britannica's cephalodia detach easily when mature, often washing off during rainy periods. They then capture the same green algae (Nostoc) found in the parent lichen, and begin to develop lobes of their own. This lichen may also reproduce through the spores contained in its "painted-fingernail" apothecia (photo, right). Many lichens demonstrate more than one reproductive strategy, insurance for their survival.

Lettuce Lung

Day 65: Excerpts from a letter to Arnie:

"That sound you hear is me beating my head on the wall.

"Bruce McCune's new books are making me painfully aware that there is absolutely NO hope of making a positive field identification of any but the most common lichens in the Park, and that probably 30-60% of our herbarium specimens are misidentified.

"In trying to ID a crustose species, I read what he had to say about Placopsis gelida, a species growing adjacent to the specimen in question. As far as I can tell, the only herbarium specimens of Placopsis taken from the Park have all been identified as gelida, but according to McCune, that's probably wrong. P. gelida is "a more northern species, rare s. of Canada." He further goes on to state that the only way to tell it apart from P. lambii is through TLC (thin-layer chromatography). (Right...now you know what I want for Christmas next year...)

"Other species require complex chemical tests to determine the presence of various lichen substances...I don't have the skills or the facility even if I did have the reagents, and I doubt the Park's little lab is adequate to the task either.

"It looks more and more like field work will just give you a 'best guess' and maybe get your specimen in the right genus (or maybe not). Otherwise, we're just bumbling along here and really can't tell what we have in the Park. Crow is feeling very frustrated right now, and about ready to go back to the 'Oh, look! Isn't that pretty!' level of research."

Trypophobia

Day 30: This will sort out which of my readers are trypophobic! The term describes an irrational dread/fear of small holes or bumps, and Lecanora pacifica's apothecia certainly qualify as the latter. Tiny, they rarely exceed 1.2mm, so it takes a good eye to find them even though they are common on alders in the Pacific Northwest. The lichen thallus (body) is white or yellowish, and the apothecia may appear in a range of shades from pale pinkish-yellow to almost black. Some disks may exhibit more than one colour. I never walk the Bud Blancher trail without checking this tree. I guess I must not be trypophobic.

Cladonia Squamosa

Day 23: Sufficiently variable in form to confuse budding lichenologists, Cladonia squamosa is quite common on the west side of the mountains, most often found on rotting wood. A few points (or lack of them!) are helpful in narrowing down the species, if perhaps not the subspecies. Brown apothecia are uncommon, but if you're lucky, that will give you a starting point as will a dense layer of squamules (scales) on the short, squat podetia (stalks). These squamules dislodge fairly readily and often leave the white medulla exposed. The medulla darkens on exposure, so sometimes the lichen has a brownish tinge. Most diagnostic are the openings at the tips of the podetia (not obvious in this photo). Chemical testing is required to narrow down an identification to subspecies.

Lobaria Oregana, Lettuce Lung Lichen

Day 140: Several varieties of Lung Lichen grow in abundance in the lowlands of the rainy Pacific Northwest. Lobaria oregana is one of the most common; in fact, one source states that in an optimum habitat, it may attain a biomass equivalent to 1 ton per hectare. This species can be distinguished by its unique colour and a lavish fringe of lobules embellishing its margins. Like other Lobarias, Lettuce Lung is pollution-sensitive, and thrives in the clear air of old-growth forest. Generally found on coniferous trees, it may also colonize deciduous species.

Baeomyces Rufus, Brown Berets

Day 98: It's always a thrill for me to find and identify a new lichen for my Life List ("and identify" is the qualifier), but I am a little ashamed to admit that this this dense colony of Baeomyces rufus (Brown Beret Lichen) was growing on a group of Cladonia-bearing rocks which I have studied minutely on several occasions. How did I overlook it? It may have been that the apothecia were just developing and I may have dismissed it for Icmadophila ericetorum, guilty of the sin of not looking closely enough to see the white podetia beneath the pinkish-tan berets. Icmadophila ericetorum is stalkless, but also grows from a pale green thallus (one of the most peculiar colours I've witnessed in nature). Baeomyces' thallus is slightly more yellowish, and at least with these specimens, less uniform. Under a magnifier, the thallus is revealed to be finely squamulose (scaly) or warty, but it's those little white stalks which set this species apart from Icmadophila and give away its true identity. Suffice to say that finding it in profusion at this location was quite a surprise! That'll teach me to pay attention to the whole picture, and not just the first thing which catches my eye.

Scoping Out Spray Paint

Day 63: The pinkish apothecia of Spray-Paint Lichen (Icmadophila ericetorum) seldom measure more than 3 mm. in diameter and are hardly noticeably to a casual observer. The blue-green crustose thallus will be the first thing to catch the eye, but it is quickly dismissed when the apothecia are discovered. However, under the microscope (large circle), the thallus is revealed to be a lumpy, bumpy world all of its own. Where many lichens appear leafy (foliose), Icmadophila is grainy, a characteristic which allows it to retain precious moisture during dry weather. Every dewdrop counts when you're a lichen!

Peltigera Membranacea, Membranous Dog-Lichen

Day 60: In yesterday's post, I mentioned the rhizines which appear on the underside of Peltigera membranacea's "leaves" (the thallus). These brown structures are its apothecia, the fruiting bodies which produce the lichen's spores. Their resemblance to badly ingrown toenails is one of the defining characteristics of the species. Other Peltigeras produce similar apothecia at the tips of their lobes, but none is so markedly curled as that of Membranous Dog-Lichen. Why "dog?" I honestly don't know, unless it is because they are lightly furry. The Peltigeras are divided into two groups. "Dog-lichens" exhibit a tomentum (fuzziness) on the upper surface (refer to yesterday's glossary) and "Pelt lichens" which are either shiny or rough (scabrose). To further confuse matters, the Peltigeras are often referred to generically as "the Pelts."

Totally Tubular

 Day 52: A number of very similar tube lichens grow in the Pacific Northwest, and a dissecting microscope and chemical testing may be needed to differentiate them. For the most part, the Hypogymnias feel somewhat like fragments of balloon, i.e. rubbery and limp, and will stretch significantly without tearing. The lobes are hollow, as can be seen in many cases by close observation of the tips (upper left). The lower surface is black, and the upper surface may be flecked with black pycnidia as well. The apothecia are generally large and obvious, and may be perforated at the center (lower right). The Hypogymnias occur commonly on conifers including Douglas fir. Absence of smaller lobules along the margins of the main lobes suggests that this specimen from Longmire is Hypogymnia apinnata (as opposed to H. enteromorpha which exhibits that characteristic).

Sectioning For Spores

Day 52: I am extremely grateful to Dr. Irwin Brodo (author of the forty-pound field guide, "Lichens of North America," and Ernie to his friends) for his patience in instructing me how to section lichen apothecia in order to reveal the spores. I can now do a much better imitation of a microtome than previously. We have not positively identified this specimen as of this writing, but evidence suggests that it is Alectoria sarmentosa, a common species often found growing on Douglas Fir. The sample on the left was scraped from the apothecial disk of a dry specimen; the one on the right is fresh material. My new microscope is proving to be a valuable tool in furthering my knowledge of lichens.

A Tangled Web

Day 50: I thought I had this figured out, but when I got a small specimen home and began examining it, I was forced to rethink my identification. Faced with two new options, I subjected a section to chemical analysis. It tested negative for a chlorine reaction, eliminating Alectoria sarmentosa from the running. Still, it didn't quite fit the brief for Ramalina thrausta because the tips of the finer branches lacked the typical curl. Apothecia were very rare (a characteristic of that species); I examined hundreds, literally hundreds of examples in the Longmire compound and only found two clumps where apothecia were present, and they were within inches of each other behind Macy Dorm. Admittedly, Brodo (the "forty-pound field guide") only contains about 30% of North American lichen species, but I would think that as common as this Ramalina is at Longmire, it must occur elsewhere in the Pacific Northwest. I hesitate to classify it as R. thrausta, although I suspect that's what it is.

Footnote: I felt silly asking about a common lichen, but this one can be tricky. I contacted Dr. Brodo who said he believes it is Alectoria sarmentosa (I should have done a KC test instead of a C). He suggested checking the spores under the microscope. I did, and they seem to confirm the identification but for one thing: they're blue, not brown. We're still hashing it out.

Aptly Named "Sunburst"

Day 19: While a lot of lichens have some rather strange common names (Frog Pelt, Ticker-tape, Volcano, Deflated Tube), the logic behind "Sunburst" is obvious. Its Latin nomenclature reflects its colour and abundant apothecia: Xanthoria polycarpa, i.e., "xanthous" (yellow) and "many-fruited." It occurs farther inland than its cousin X. parietina, a species which in any event is rather rare on the west coast. Look for the apothecial disks which distinguish it from Candelariella vitellina (Common Goldspeck). Sunburst will be found on tree bark, Goldspeck almost always on rock.

Common Freckle Pelt, Peltigera Aphthosa

Day 101: Nothing excites me more than finding and identifying something I haven't previously catalogued. It doesn't have to be a rare species, although that's certainly a bonus. It just needs to be new to me. As many times as I've walked around Longmire Campground, I have failed to notice the abundance of this "pelt" lichen until today when the brilliant green thallus drew my attention during a rather wet lunchtime patrol. Later on my walk, I discovered several colonies in fruit, the large mahogany-brown apothecia sticking up like little flags. The scattered cephalodia (greyish-black dots which contain cyanobacteria) are what give this lichen its common name, Freckle Pelt. It is one of four species which host a green algal photobiont, the photosynthetic component of a lichen. In Peltigera aphthosa, this component turns brown when dry or when exposed to sunlight, undoubtedly the reason I overlooked it until now.

Spotlight On Cladonia Bellidiflora

Day 46: C. bellidiflora is a fairly common Cladonia here in the Pacific Northwest, and perhaps its success is due to the abundant squamules which typically cover its podetia. Okay, I threw a couple of unfamiliar words out there and to save my readers from having to scramble to their dictionaries, I'll explain. A lichen's stems are called "podetia" (singular "podetium") and the squamules are the little leaf-like structures growing along them. These "leaves" allow the lichen to trap nutrient-laden moisture and conserve it in the dry season. "Apothecia" are the fruiting bodies of the lichen (in this species, bright red knobs). Cladonia bellidiflora is particularly showy, although generally, most people walk right by colonies unless the apothecia are readily evident and happen to catch a hiker's eye. It is one of several "lipstick" lichens you'll find in our forests, and in my experience, seems to have a preference for decaying cedar stumps and logs.

Lettuce Lung, Lobaria Pulmonaria

Day 159: What urged me to walk back to the site of yesterday's froggy encounter was this specimen of Lettuce Lung (Lobaria pulmonaria) on which the seldom-seen brown apothecia (fruiting bodies) were clearly apparent. Although the lichen is abundant in this area, I observed apothecia only on this one example. Lettuce Lung prefers old-growth forest and is sensitive to atmospheric pollutants, so if you happen to find yourself where it grows, you may be assured that you're breathing clean air.