• Searching for Jelly Lichens

    Spring is brief in Colorado, making it very important to play hooky this time of year! This post records an adventure from back in May 2009, a wetter spring than Colorado has had in recent years. That made it a perfect time to visit Lair o’ the Bear Park with a friend to see jelly lichens.  

    I hadn’t visited for a while, so had to check every cliff to find the right one, way out at the west end of the creekside trail that was once the main road from Morrison to Evergreen, shortly before it enters adjacent Corwina Park.

    Eventually we reached the proper cliff, where we could see not only the sought-after jelly lichens, but the wonderful Sticta, and verdant masses of spikemoss, Selaginella. The jelly lichens were soft and slimy from recent rains and lingering rivulets in the cracks and crevices of the cliff. In this photo, a large Umbilicaria (lichen, not a jelly one) is under the ring, with dark Selaginella to its right, and lighter-colored masses of true mosses surrounding.

    Properly called gelatinous lichens, these lichens are so named because they lack the firm texture of more typical foliose lichens and have a characteristic translucence when wet. (They remind me of the “tree ears” we sometimes encounter in Chinese restaurant dishes, but those are actual fungi.) Gelatinous lichens are unstratified or only partially so, lacking the distinct algal layer, and sometimes the firm lower and/or upper cortex found in the “typical” lichen (if there is such a thing). The primary phycobiont species is a cyanobacterium, generally Nostoc.

    They look so different when they’re dry! This one is, I believe, a species of Leptogium, with a white tomentum visible on the lower surface. Perhaps L. saturninum, but confirmation will have to await another trip. With a hand lens. For those who prefer common names, LoNA* calls this one bearded jellyskin.** (Ugh!)

    By the way, you can sometimes find free-living forms of terrestrial Nostoc in Colorado (more commonly here in NY). We’ve seen them on Lyons Sandstone near Red Rocks Park.

    * LoNA is Lichens of North America, the coffee table book of lichens, by Brodo, Sharnoff, and Sharnoff. Highly recommended! You can see Sharnoff’s species photos from the book at Sharnoff Lichen pages.

    ** Jellyskin is the name used here for the entire genus of Leptogium, as opposed to the name “jelly lichen” given only, in that book, to species of Collema, another common jelly lichen. This is the only book I know that assigns common names to lichens; few lichens have true common names.

  • Lichen Spotlight – Vulpicida pinastri

    The Powdered Sunshine Lichen or Vulpicida pinastri is certainly one of the most striking of Colorado lichens. For those of us who like to identify lichen to species it also happens to be highly distinctive!

    Vulpicida pinastri – Gregory Canyon, Boulder CO

    This species is quite common once you know where to look for it. It likes cool wetter areas in the higher areas of the foothills up to timberline. It is a corticolous lichen, fancy scientist speak for growing on trees of bark. The species has a particular fondness for stumps, especially where humans have cut down a tree. Like other species that prefer exposed wood and not bark, it also grows on other human-made substrates like fences.

    It can be rather immediately identified by its erect foliose structure, the intense yellow marginal soredia that look like a crust on the outer edges of the lichen, and a blue-green thallus. This species is almost always sterile, meaning the lichen only reproduces asexually by the dispersal of tiny particles of those beautiful yellow soredia.

    Vulpicida pinastri on an old stump, a common substrateGregory Canyon, Boulder CO. Click to enlarge.

    I tried to find more about the species’ natural history, and like many lichens there is not much out there. It is a Holarctic species distributed in northern hemisphere in both North America and Eurasia. It can be found in boreal forests and at higher elevations in mountains further south. That’s us in Colorado! One study1 used this species to show that some lichen substances are indeed toxic and are a possible way to limit anything from eating them. Another presentation2 made the bold claim that chemicals produced could have potential in the treatment of Alzheimer’s! At any rate surely there is more to learn about this lichen, but for now head up into the mountains and try and spend some time with your new acquaintance Vulpicida pinastri.

    1 Pöykkö, H., Hyvärinen, M., & Bačkor, M. (2005). Removal of lichen secondary metabolites affects food choice and survival of lichenivorous moth larvae. Ecology, 86(10), 2623–2632. https://doi.org/10.1890/04-1632

    2 Ureña Vacas, I. M., González Burgos, E., & Gómez-Serranillos, M. P. (2019). Antioxidant capacity and cholinesterase inhibitory activity of vulpicida pinastri lichen and its chemical composition. Proceedings of 5th International Electronic Conference on Medicinal Chemistry. https://doi.org/10.3390/ecmc2019-06317

  • Life Finds a Way

    Underpass to the Highway 36 onramp on Baseline Road, Boulder.

    You may well be asking why on earth I have started this post with a picture of an underpass, but on a windy day in Boulder here I was.

    I have always been fascinated by the life that manages to persist in heavily disturbed urban areas like the plants sprouting through cracks in the sidewalk. While sometimes easy to simply dismiss the life that persists in these places, to wish that native species could be flourishing instead of the non-native weeds, bugs and animals, I think learning what can live in the midst of all of humanity is a worthwhile task. As I set off my soap box I present to you one such organism.

    Flavoplaca citrina (tentative) – Growing on a synthetic fiber. See the retaining wall on the left side of the top photo and you can just barely see the black material with yellow crust on top.

    I was quite surprised to see large patches of a yellow lichen growing on some material presumably used to help keep the dirt in place on the retaining wall. I was even more surprised when I looked closer and determined it was a species I had clearly never seen before. When attempting to key out this specimen I had no good answer it asked me what substrate it was growing on! If you believe it construction material wasn’t an option. Presuming I have the species correct in Tom Nash’s excellent Lichen Flora of the Greater Sonoran Desert Region. Vol 3 possible substrates for the species are “on wood, bark, bryophytes, non-calcareous or calcareous rocks.” This to me shows that the species can be rather opportunistic when it comes to where it can grow. Perhaps a reason it chose this man-made material as a home.

    Next time you are on a walk through the city and you see a splash of color where you don’t expect take a closer look you may just find a lichen adapting to the new urban environment we have created.

    Flavoplaca citrina (tentative) – Showing off it’s apothecia (bright orange discs with yellow rims) which were present on some but not all colonies of the lichen.

    One of the main reason’s I wanted to start writing on lichens is to show others how to start identifying them. So watch out I’m going to get technical down here and describe this lichen.

    Let’s start with a description of the thallus. Step one, it has a thallus, this is the yellow portions in the above photo, and is the main body of the lichen. In some of the small crustose species the entire thallus can be hidden within the substrate and only the apothecia are showing. The thallus also has no distinct leaf-like shapes at the edges (non-lobate) and only consists of little individual specks (areolate).

    Second step color, yellow and orange lichens are rather distinctive and, in general, are going to belong to only a few groups of lichens. When presented by a new yellow or orange species a chemical test with Potassium Hydroxide solution is a good step. Lichen aficionados call this a K test. Fun fact K is a product used for some dermatological applications and is super easy to buy. Please inform your spouse before they ask why you purchased foot fungus medicine. I digress. Treat a small section with the reagent and it may well turn blood red. If this is true you have a member of the family Teloschistaceae, as was true today.

    Next step is describe the reproductive structures (I hope for a full post about this soon). In the last photo we have apothecia disc or cup shaped structures, but looking closer there is more.

    Microscope view of the areoles (the individual units of yellow above). A continuous thallus is not divided this way. See also the marginal soredia.

    Looking closer we see powdery masses on the margins, these are soredia. This powder can disperse in the wind or hitch a ride on an animal and if it find the right place to live a new lichen can form. Lichens are weird, as you may have picked up on, this specimen reproduces both sexually (apothecia) and asexually (soredia). Talk about keeping our options open.

    Hopefully those that kept reading learned a new term of two. Identifying lichens can be extremely hard, and a good key is necessary, or even specialized equipment. If you think I blundered this ID (very likely) let me know I would love to know why.

  • An Introduction

    Hello! I am very excited to introduce myself. My name is Nick Moore. I am looking forward to sharing the world of Colorado Lichens and I hope to be a regular contributor to this wonderful site that has been built over the years.

    So who am I, you might ask. I am someone who has always loved nature, who only recently decided to learn the ways of lichens, and has leapt headfirst into this new world. Hopefully those that stumble across these posts want to come along for the ride.

    Why don’t we start with some of my favorite local species. These are some charismatic species that can be found on just about every hike through the lower foothills of Boulder County.

    Rusavskia elegans – Anne U White Trail, Boulder CO. On Granite

    By far the most common orange lichen on rock along the front range. Older references may refer to this species a Xanthoria elegans.

    Pleopsidium flavum – Mount Sanitas, Boulder CO. On Granite

    The answer to what’s that yellow on that rock over there along much of the front range. This lichen has an amazing need to be on vertical rock faces.

    In a prelude to what I hope will be a future blogpost this species has been taxonomically unsettled in the state. So I would not be surprised to someday learn that this is the wrong name for this lichen or even that multiple species are involved. That day may come as soon as the right person reads this paragraph!

    Dimelaena oreina – Mount Sanitas, Boulder CO. On Granite

    Perhaps my favorite front range lichen. Once you learn it you will find it very common on sunny exposed rocks. But, unlike the previous species you will find is accompanied by a whole host of similar colored species. Identifying lichens is hard, observing them in all their beauty is easy.

    Parmelia sulcata – Button Rock Preserve, Boulder CO

    Start walking up your favorite foothill trail. When you get to a nice cool spot under the shade of a big conifer, look down into the tangle of moss and lichen at the roots of the tree. One of the lichens you find is sure to be this wonderful foliose lichen and you’ll soon find it on other substrates as well. Just be sure to note the raised web of white tissue forming what look like cracks (pseudocyphellae) characteristic of the genus. Keep searching and you will find that sulcata is not the only member of the genus present in Colorado.

    I hope you enjoyed the post. Perhaps you noted that each photo here links to my iNaturalist observation for the lichen. I hope to have iNaturalist be a constant part of my posts here, and you can always see more of my photos by searching for @nickmoore91. I post everything from birds, insects, fungi and more. Feel free to reach out!

    My CO Lichen Observations – Warning some non-lichenized ascomycete fungi show up in that search!

  • Welcome, 2022!

    Changes are afoot here at Colorado Lichens. After long dormancy, we’ve relocated and cleaned up a bit, and the transition is mostly complete as of March 17. After five years’ absence from Colorado, I don’t know that I have much more to say about the lichens of that lovely state, and will actively seek an interested party to assume this domain and perhaps some of its content.

    It looks as though everything is working properly, although you may stumble across missing images. If that happens, please let me know— I’ll have a contact form up soon for reporting issues and general comments.

  • Iceland “moss,” Cetraria islandica

    Cetraria islandica, a true lichen known as Icelandic moss, captured as an ingredient in “Icelandic schnapps.”

    An unexpected encounter last week reminds me to talk about one of my favorite lichens! Cetraria islandica is not entirely rare in Colorado, but I would guess it’s rarely seen by most of us. For one thing, it occurs at higher elevations, above, say, 8000 ft. (~2440 m) It’s also cryptically colored, blending in with the forest floor, where it can be confused with other small plants, mosses, and lichens carpeting the soil.

    Steeped in alcohol, "Iceland moss" becomes Icelandic schnapps—definitely an acquired taste.

    Steeped in alcohol, “Iceland moss” becomes Icelandic schnapps—definitely an acquired taste.

    But the lichen I encountered last week, at a friend’s house, was in a bottle, lending flavor and perhaps substance to a concoction called Icelandic schnapps. Of course, I had to taste it, and he was kind enough to oblige. Knowing he had laboriously carried it home from a visit to Iceland, I did not ask for a second glass.

    Cetraria islandica is one of a few species known to occur in Colorado, although they will be more common at higher altitudes (or latitudes!). All are fruticose, after a fashion, and more or less brownish in color. (Clarity is helped here by the fact that the yellowish species are now in a separate genus: Flavocetraria.)

    According to CNALH: “Cetraria ericetorum is distinguished from C. islandica … by having a consistently P- medulla, and by the pseudocyphellae being strictly marginal and sometimes indistinct or absent. Cetraria ericetorum ssp. reticulata belongs within the C. ericetorum complex comprising three mainly geographical races. Subspecies. reticulata basically comprises the subspecies occurring in North America.”

    Cetraria aculeata is more truly tangled and shrubby, its branches more rounded than flattened. It was once in a separate genus, called Cornicularia.

  • ID Tips for Lichen Newcomers

    How do you start figuring out lichens if you’re a novice, especially if you have no keys? With 85% of my books, including lichen ID materials, still in storage (long story), I’m thrown on the resources of the internet. Here are a few suggestions for exploring lichen basics (off-site links open in a new window):

    Guide to British Lichens on Twigs, with picture key! Click to go to site.

    Guide to British Lichens on Twigs, with picture key! Click to go to site.

    There is an online lichen key from the UK for 60 British lichens on twigs (from the Natural History Museum at South Kensington); they also have a glossary of terms. To get started, choose whether the lichen is fruticose, foliose, or crustose. (See descriptions at our Shapes and Sizes page if you’re not sure.) You eventually get to a color photo of the lichen. If you get one or more results, don’t assume the species is right, but it might at least point you to a genus to check out. (I got a lot of “no results” on my searches, but I was just making up characters.)

    You might try checking photos at Ways of Enlichenment, which does a good job of showing many species in each genus.

    Steve Sharnoff offers some lichen basics at his website. He also has lots of photos available that may also be helpful, but this site is focused on North America. Some species, however, are widespread, and many genera are.

    If you narrow it down to a few species, you can check whether they occur in your area at this database maintained by the Consortium of North American Lichen Herbaria (CNALH). Their records include specimens from all over the world. If you go to their dynamic map and click on your area (and specify a radius to search), they will generate a checklist that you can also use as an interactive key. Very nice!!

    Only the lichen portal at CNALH will give you a detailed description of important characters, but at least the others provide visual references.

    Note: Also posted this on iNaturalist as a journal entry.

  • The Latest Lichen News

    Yes, we’re back, and there’s news in the world of lichens. Please forgive the long “dormancy,” of which more is explained below. But right now, things are popping in the world of lichens, and we thought we’d better attempt to update ourselves just a tad.

    The Overlooked Organisms That Keep Challenging Our Assumptions About Life, at The Atlantic. As they say, “Gorgeous and weird, lichens have pushed the boundaries of our understanding of nature—and our way of studying it.” (by Ed Yong Jan 17, 2019)

    [Or maybe not so “latest” after all. Here’s an earlier article about the researcher who put this idea together, Toby Spribille, also by Ed Yong, in the Atlantic in 2016.]

    We’ve talked before about the fact that some lichens contain multitudes—specifically, representatives of not just two but THREE kingdoms within their symbiosis. Now, researchers are demonstrating that the situation for some lichens may be even more complex.

    Hooray for lichens—the organisms that continually surprise us!

    Lichen-forming fungi [all*] belong to a group called the ascomycetes. But in 2016, Spribille and his colleague Veera Tuovinen, of Uppsala University, found that the largest and most species-rich group of lichens harbored a second fungus, from a very different group called Cyphobasidium. (For simplicity, I’ll call the two fungi ascos and cyphos).

    Bright green Letharia vulpina outshines pale Usnea in this photo from C. Tom Hash (https://www.inaturalist.org/users/7893, used by permission).

    Bright green wolf lichen (Letharia vulpina) outshines pale Usnea (beard lichens) in this photo from C. Tom Hash (https://www.inaturalist.org/users/7893, used by permission).

    Look on the bark of conifers in the Pacific Northwest, and you will quickly spot wolf lichens—tennis-ball green and highly branched, like some discarded alien nervous system. When Tuovinen looked at these under a microscope, she found a group of fungal cells that were neither ascos nor cyphos. The lichens’ DNA told a similar story: There were fungal genes that didn’t belong to either of the two expected groups. Wolf lichens, it turns out, contain yet another fungus, known as Tremella. —Ed Yong

    * There are, as I understand it, a few lichen-forming Basidiomycetes as well. But for practical purposes… ascomycetes.



    Tremella is commonly known to us ordinary mortals as “witches’ butter” and is a parasitic jelly fungus that seems to be fairly distinctive. I posted this photo on iNaturalist, however, and haven’t had anyone confirm its identity to date.

    Tremella fungi had been reported from wolf lichens previously, but were thought to be “secondary” to the main symbiotic relationship. The “news” here is that these extra fungi may, in fact, be quite central to the concept we call lichens. At least in the genus Letharia. We’ll be staying tuned to new developments!

    Yes, I’ve recently been getting active on iNaturalist (@slwhiteco), and am especially intrigued by checking out the lichens there. Unfortunately for me, lichen taxonomy has changed significantly since I studied them back in the Darkish Ages. Apparently the advent of DNA analysis has stimulated, or required, major revisions in groups, and I’m still trying to untangle the implications. Perhaps we’ll explore a few of them in a future post.

    My other complicating factor is that I’m no longer in Colorado. The move, and preparations for it, were a significant distraction from this website, but we’ll hope to bring you more lichen material in the future. Sadly, other than several Cladonia and some corticolous species, I’ve not found good lichen-hunting in this part of upstate New York yet.

  • California gets a State Lichen!

    This month, California became the first state to designate an official State Lichen. Based on the efforts of the California Lichen Society, the state legislature approved the lichen last summer and the law was signed by Governor Jerry Brown in July, but didn’t take effect until January 1, 2016.

    Ramalina menziesii, lace lichen. Photo courtesy Greg Howe.

    Meet Ramalina menziesii,
    the Lace Lichen

    finRmenziesiiAlthough one of several lichens that drape themselves in trees in long graceful strands, the Lace Lichen is distinctive and instantly recognizable. Unfortunately for the rest of us, this beautiful lichen occurs only along the west coast of North America. However, this makes it a perfect candidate for California’s state lichen: it is common along the coast and as much as 130 miles inland. No other lichen has the lacey or netted branches, although some species of Usnea or Alectoria appear similar from a distance.

    Learn more about Lace Lichen and its designation at the California Lichen Society webpage. But remember, it’s a lichen, not to be confused with “Spanish moss” (which is not a moss either)!

  • Lichens by Haeckel 1904

    Lichenes illustration by Ernst Haeckel, labeled to match the key below. Via Wikipedia, public domain.

    Lichenes illustration by Ernst Haeckel, labeled to match the key below. Via Wikipedia, public domain.

    Via Wikipedia, this great illustration of “Lichenes,” drawn by Ernst Haeckel to emphasize his ideas of symmetry in his Artforms of Nature, published in 1904. Click to enlarge.

    Haeckel’s stylized drawings convey these lichens in their most basic forms, with much of their random meandering growth reduced to precision, as evidenced in the strict circles of #8 and #9, the ovals of #10 and #11. Despite the fact that, in the field, these are apt to appear far less uniform in shape, Haeckel has captured the “personality,” if you will, of each species, making them reasonably recognizable.

    Just for fun, in the key below, we’ve linked some of the species names to a current photo from other websites for comparison. Links open in a new window; use your browser’s back button to return here.

    Tafel_083_schema_300Here’s the key to these drawings, by number, with some synonymy of a more recent day added, apparently by the annotator for Wikipedia.
    1. Cladonia retipora (Floerke) = Cladia retipora (Labill.) Nyl. (an Australian species, but here’s a photo from Pinterest)
    2. Cladonia perfoliata (Hooker) = Cladonia perfoliata
    3. Cladonia verticillata (Achard) = Cladonia cervicornis ssp. verticillata (Hoffm.) Ahti
    4. Cladonia squamosa (Hoffmann) = Cladonia squamosa (Scop.) Hoffm.
    5. Cladonia fimbriata (Fries) = Cladonia fimbriata (L.) Fr.
    6. Cladonia cornucopiae (Fries) = Cladoniaceae sp.?
    7. Sticta pulmonaria (Achard) = Lobaria pulmonaria (L.) Hoffm.
    8. Parmelia stellaris (Fries) (non (L.) Ach.: preoccupied) = Physcia stellaris or Physcia aipolia (Ehrh. ex Humb.) Fürnr.
    9. Parmelia olivacea (Achard) = Melanohalea olivacea (L.) Essl.
    10. Parmelia caperata (Achard) = Flavoparmelia caperata (L.) Hale
    11. Hagenia crinalis (Schleicher) = Anaptychia crinalis (Schleich.) Vězda

    If you appreciate the elegance of nature, as Haeckel clearly did, you should look at this entire book. Browsing through the illustrations was like an instant review of invertebrate zoology and paleontology courses from college. Many of his drawings feature protozoans, medusoids, and other familiar lifeforms in those textbooks (if not in life); these would have enhanced some of those courses! Explore more at:

    Kunstformen der Natur, Haeckel, Ernst, 1834-1919, Bibliographisches Institut Leipzig. Contributed to Biodiversity Heritage Library by University of Illinois Urbana Champaign.