Lichens
December 16, 2007
Bryoria fuscescens
Apologies for the late entries recently – I'm finishing up a big project (that you'll get to see at the end of January or so) and all that goes with that, so opportunities for rest are taken when I can get them.
I'm fairly certain of the identity of this lichen, though it could be another species in the genus. If it is Bryoria fuscescens, its common name is speckled horsehair lichen or pale-footed horsehair lichen. The epithet fuscescens means “becoming dark”. The related Bryoria fremontii is regarded as “the most widely used edible lichen in North America” (see edible horsehair at the Lichens of North America site).
Bryoria fuscescens is widely distributed across North America and Europe, particularly in association with montane and boreal forests. It is commonly found on conifers.
Posted by Daniel Mosquin at 10:46 AM| Comments (5)
August 28, 2007
Verrucaria maura
Thank you to Stephen B of Scotland aka stephenbuchan@Flickr for sharing today's photograph (original). I've been wanting to feature this species for a while, so much appreciated, Stephen!
If asked to create a list of familiar organisms by the seashore (and lived in a temperate area), I'm betting that most people would not include “lichen” on the list. Narrowing it down to a list of the organisms in the intertidal (the band of life between the high-tide and low-tide marks), and I'm still willing to bet lichen would be absent from most lists. Mussels, yes. Barnacles, yes. Seastars, likely. Seaweed, yes. Lichen? Not likely, unless you know that the black patch of what looks like oil residue is not what it first appears to be.
Sea tar or black seaside lichen is found along coastal rocky shores throughout much of the temperate parts of the world. In these areas, it is often a component of the upper intertidal zone and, above that, the salt-spray zone. To give a rather unscientific example of how it is overlooked, its near-constant intertidal companion with a similar distribution range, Mytilus edulis (or blue mussel / common mussel) receives nearly 600 000 hits on a popular search engine; Verrucaria maura? Fewer than a thousand.
The UK-based Field Studies Council has a small article about tar lichens in general, and a specific page about Verrucaria maura as well. Through photographs, Seaweeds of Alaska reveals how Verrucaria maura can be seen from the air. A closer photograph of the banding caused by lichens is displayed in a story about lichen study in the Gwaii Haanas National Park Reserve of British Columbia: Time for Nature – Learning About Lichens.
Posted by Daniel Mosquin at 6:20 AM| Comments (5)
June 24, 2007
Letharia columbiana
Botany Photo of the Day will have brief written entries on weekends, holidays and my vacations from April through September. – Daniel
Brown-eyed wolf lichen is considered one of two species in the genus Letharia (the other being Letharia vulpina). At first glance, it is readily distinguished from its counterpart by the presence of brown apothecia. However, read Susanne Altermann's “A Second Look at Letharia (Th. Fr.) Zahlbr” (PDF) from the Winter 2004 Bulletin of the California Lichen Society for information that suggests the classification of species in the genus might be a bit more complicated than at first glance.
Posted by Daniel Mosquin at 12:00 AM| Comments (1)
March 25, 2007
Letharia vulpina
It's been a while since I've shared one of these types of images. Letharia vulpina growing on an old, fallen log of Pinus ponderosa.
Natural history resource link (local): Volker of Surrey, British Columbia recently shared his weblog with me: Haliaeetus. Volker shares his nature and seasonal observations through photography and commentary.
Posted by Daniel Mosquin at 5:52 AM| Comments (5)
February 16, 2007
Lichen Diversity
This is a companion image and written entry to a previous BPotD on lichen diversity, though it was photographed three months earlier and 900 km (~550mi) away from the other image. I was pleased to discover lichen-covered rocks in Grasslands National Park, as it was an unexpected photographic dimension in exploring the area; I'd anticipated the skyscapes, the endangered species and the wildflowers, but not the lichen patterns.
In comparison to the crustose lichen-covered rock in the other entry on lichen diversity, I would expect the process of succession to occur over a much larger time scale. Dessication, temperature extremes, wind abrasion and fewer moss and vascular plant colonizers create conditions where the reign of the lichens is unlikely to be toppled for centuries, if not millenia.
On a different topic, I had the opportunity to walk around the garden for a small time yesterday, and noted that spring is tentatively making an appearance. I imagine 2007 photographs will soon start to become common on BPotD.
Posted by Daniel Mosquin at 6:04 AM| Comments (1)
September 2, 2006
Cladonia spp.
Two folks from British Columbia contributed today's images, both submitted via BPotD Flickr Group Pool. Lotus J., aka ngawangchodron@Flickr submitted the first image (original image) and Brettf@Flickr submitted the second (original image). Thank you to both of you, much appreciated.
Both photographs demonstrate a member of the genus Cladonia, or cup lichens. One of the distinguishing features of Cladonia is a two-part body consisting of primary thalli and podetia. Primary thalli and podetia are present in both images; the thalli are the “flat little crusty green bits” (most of what can be seen in the first photograph, but not as ubiquitous in the second) while the podetia are the stalked structures. The red parts on the end of some of the podetia are apothecia, a particular type of spore-bearing structure.
Identification of Cladonia can be difficult, and I haven't spent a lot of time attempting to identify the one in the second photograph, though it should be possible with the podetia present. Identifying Cladonia before the podetia are developed, however, is difficult beyond recognizing that it is a Cladonia. As Trevor Goward writes in Plants of Coastal British Columbia: “Though easy to recognize as a group, the cladonia scales are notoriously difficult to identify to species. Still, it can be ‘fun’ trying (consult a technical manual such as Thomson 1967).”
Photography resource link: Photography Locations via The Luminous Landscape. Finding where to photograph can be difficult (especially when travelling), so resources like these are very helpful. I only wish such a thing existed for wildflowers, since this resource concentrates on landscapes.
Posted by Daniel Mosquin at 12:00 AM| Comments (3)
February 7, 2006
Hamamelis ×intermedia 'Fireglow' and Evernia prunastri
Updated February 7, 2006 at 4:06pm: Thanks to Doug who suggested some alternatives to my tentative identification in the comments, I went out and re-examined the lichen. I'm now reasonably confident that this is Evernia prunastri and not what I misidentified it as, Platismatia stenophylla. I think it's an opportune time to remind you that I'm more interested in having the correct information available to BPotD readers than I am in being “right”. If I ever post something that doesn't sit right with you or if you can add something (including a different perspective!), please comment – Daniel.
Mysteries abound, today. Let's start with the lichen. I'm fairly certain it is Platismatia stenophylla or ribbon rag lichen, but it's difficult to confirm. I've only one image in a book to compare with, since there are no results in image search engines for either Platismatia stenophylla or a synonym, Cetraria stenophylla. Nope, I was wrong – Evernia prunastri is a better match. This taxon's native range of occurring in coastal forests of temperate western North America matches, as does its property of growing on trees – so perhaps I'm right. To help be certain, I'd have to break out the chemistry kit. As I've noted before, lichen identification is often aided by observing reactions to chemical reagents (if you ever see a person in a forest with a satchel of small bottles covered by eyedroppers, you will have encountered a bona fide lichenologist).
For Platismatia stenophylla Evernia prunastri, confirming that it is either KC+ (yellowish) or KC- would help verify my tentative identification. This test would involve first wetting the thallus (body) of the lichen with a ten percent potassium hydroxide (KOH) solution, or the K test. The C test would be a dose of bleach, that is, a solution of sodium hypochlorite. If there is no apparent reaction to the bleach on the KOH-soaked lichen, another bit of evidence would be in agreement with the identification. If the test was positive, however, the thallus would change colour. For this lichen, a change to a yellowish colour would help confirm. If it changed a different colour, I'd be back to scratching my head over other possibilities.
The Oregon Coalition of Interdisciplinary Databases has a good entry on Evernia prunastri, and image search comparisons also suggest a match.
The hybrid witchhazel poses a different sort of mystery. Occasionally in the past few years, some staff time has been invested in attempting to verify that a cultivar 'Fireglow' exists. So far, we've come up short. Staff from the garden have searched online, reviewed the horticultural literature and even contacted the International Cultivar Registration Authority for Hamamelis, all to no avail. Its existence as a cultivar could be due to something as simple as a clerical error in its thirty year history. Or, perhaps it is a locally-developed selection, named and sold only to a select few three decades ago (it was purchased from a now-closed local nursery). Too, it could be a misidentification and actually an entirely different cultivar. We haven't yet figured it out.
Photography resource link: Tripod Therapy, an article by Rod Barbee for Nature Photographers Online. Good advice regarding one of photography's most important tools.
Posted by Daniel Mosquin at 12:00 AM| Comments (11)
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Botany Photo of the Day and all associated images are licensed under a Creative Commons License.
Botany Photo of the Day is a project of the UBC Botanical Garden and Centre for Plant Research, located in Vancouver, British Columbia Canada. UBC BGCPR is a department of the Faculty of Land and Food Systems within The University of British Columbia.