Bill from San Jose, California (aka bbum@Flickr) submitted today's photograph of bull thistle (taken last July) via the BPotD Flickr Group Pool (original image). Bill has recently written about some of his experiences with nature photography on his weblog, bbum's weblog-o-mat. Thanks again, Bill!

Cirsium vulgare is native to Europe and Asia, but is now found throughout most of North America (including all of the continental US and Alaska). Part of its success as a weedy invader is due to it being a myrmecochore – a plant whose seed is dispersed by ants (in a 1973 paper in Biotropica by Fittkau & Klinge, the authors estimated the biomass of ants to be 4x that of all terrestrial vertebrates in the Brazilian rainforest – I don't know what the numbers might be elsewhere, but you can read more about ants in Wilson EO, Hölldobler B. 2005. The rise of the ants: A phylogenetic and ecological explanation. Proc. Natl. Acad. Sci. USA 102(21): 7411-4).

Dr. Peter Harris, emeritus scientist with Agriculture and Agri-Food Canada, has written an extensive article describing Cirsium vulgare, its economic impact, methods of biological control and its ecological properties. The advantages of myrmecochory are fully outlined in the article, but I'll summarize as well. Seeds transported to ant colonies are discarded (the ants eat the protein- and fat-rich elaisome on the fruit) into abandoned galleries in the nest. In the nest, the seed is: 1) protected from above-ground predation (rodents and birds), 2) provided with a nutrient-rich environment in which to germinate (if the seed is non-dormant) and 3) if it is dormant, can remain so until the seed is exposed to light. The last advantage might require some explanation. For a biennial species like Cirsium vulgare, two bad years of no seed production (due to biological controls, fire, chemical control, etc.) could theoretically wipe out a local population. However, by having buried seeds reside in ant nests that may not germinate for many years, the long-term sustainability of the entire local population of plants is secured.

Art resource link: Ruth Jones – Art of Tapestry, with images of pieces in the Galleria and Range of Work. Tapestry, like most other artwork, is certainly better witnessed in person. Still, it is possible to observe elements of composition, colour and form online (with an eye to continued attentiveness of such in photography). Site suggested by BPotD reader Margaret from Vancouver (thank you!).

Rhododendron dauricum is one of the earliest rhododendrons to bloom each year. Widely distributed in eastern Asia (including Siberia), it is recorded to be hardy to -32°C / -25°F (and hence used in hybridization work for hardiness). Elizabeth Carlhian, of the American Rhododendron Society Massachusetts Chapter, has written a comprehensive account of Rhododendron dauricum and its cultivars.

Nature / photography resource link: ARKive: Images of Life on Earth – “Using film, photographs and audio recordings, ARKive is creating a unique record of the world’s biodiversity - complementing other species information datasets, and making a key resource available for scientists, conservationists, educators and the general public.”

Today's images are of a rare snowfall in the mountains adjacent to Santa Barbara, California, taken last Sunday by Petra Cortright (petra cortright@Flickr | BPotD Flickr Group Pool) . Many thanks, Petra! As an aside, Petra was also kind enough to suggest a few locations around Santa Barbara for photography.

While taxonomists occasionally argue about the classification of plant species, analogous arguments can be heard from ecologists with regards to the classification of vegetation. What criteria should be used? Abundant species in the area? Climatic regime? Dominant plant habit (physiognomy)? Keystone species? In the system used by the World Wildlife Fund, the mountains near Santa Barbara, California are classified by a hodgepodge of location, physiogeographic features, biome and physiognomy: California Montane and Chapparal Woodlands (more info with regional map and photos). For conservation purposes, this seems like a suitable classification system. However, for current trends and suggestions for further improvement in vegetation classification, please read the Wikipedia entry on Vegetation.

Photography resource link: Lifting the Shroud: Creating an Interpretation, an essay by Michael Reichmann of The Luminous Landscape, draws attention to the notions of capturing and interpreting reality in photography.

A fairly uncommon cultivar, 'Rosevallon' is generally only seen in botanical gardens with extensive Rhododendron collections or sold by specialist nurseries. If you were to walk by this plant in the garden, it's likely that you'd miss its most striking feature: the colour of the underside of its leaves. As you can see in the first image, the leaf undersides seem to simply be heavily shadowed and are easily missed. Bending its branches, however, reveals its secrets (I wish the second photo had a bit more depth. Ah well.).

The species Rhododendro neriiflorum is native to the Himalayas. For more on rhododendrons, I highly recommend the Rhododendron Species Foundation and Botanical Garden site.

Botany resource link: Flora of Taiwan online database. We have the print version at UBC, but it's good to see the information available online. If you find the information too technical, perhaps you'd enjoy some of the images: example 1, example 2 and example 3.

When taken to abstractness, iris flowers look entirely different; it's understandable that they are favourite subject of photographers. For more literal photographs, there are a few images of Iris 'Purple Gem from previous years available on the garden's discussion forums. Alternatively, I also suggest trekking over to read Paghat's excellent written account of Iris 'Purple Gem' with accompanying images.

Photography resource link: For inspiration, Adirondack Light: the photography of Mark Hobson. Navigation is a bit tricky, so here are the three gallery links: Ku SQ Thinking, Krappy Kamera and Ku Triptychs.

Thanks to “leafdesigner” of Battle Ground, Washington for submitting this image via the BPotD Submissions Forum (original). leafdesigner previously submitted this image of Agaricus praeclaresquamosus – the fungus images are much appreciated!

leafdesigner writes: “This is Gomphus floccosus, a.k.a. woolly chanterelle. In the constantly shifting taxonomic landscape of mycology, I'm not absolutely certain this is the “true” G. floccosus, but it keyed out most convincingly that way. One thing for sure is that it is a relative of the true chanterelle, belonging to the Cantharellaceae family. Like that species, spore-bearing basidia are born not on true gills, but on blunted gill-like ridges that line the tissue beneath the cap. Unlike the true chanterelle, this species is not generally considered edible. It is, in fact, listed as poisonous in some field guides. This photo was taken in November of 2004, in Multnomah County, Oregon.”

Shifting taxonomy of mycology indeed! I did a little digging to see how much things have shifted – wow! The taxonomic information alluded to by leafdesigner above has essentially been turned on its head in the past two years. As Michael Kuo notes in The Genus Gomphus, a DNA study is now suggesting that despite a morphological resemblance to chanterelles, this genus of fungi instead seems to be more closely related to the stinkhorns and earthstars (reference information available on the Gomphus page). Once again, DNA analysis pulls the rug out from under the feet of decades of conventional thought; it turns certainties into opportunities for re-examination and a more nuanced understanding.

Despite an increasing reliance on DNA sequencing to expand comprehension of organism relationships and evolution, an understanding of its limits is also being articulated and discussed. This is a topic I will return to another day, hopefully accompanied by a photograph of one of the Vulpia (grass) species referenced in Stace, C. 2005. Plant taxonomy and biosystematics – does DNA provide all the answers? Taxon. 54(4): 999-1007).

For more information on Gomphus floccosus, see another Michael Kuo article (it leads with “You have probably met several people in your life who should have been named Gomphus Floccosus.”): Gomphus floccosus. It's worthwhile to note that the same study that discusses the relationships of Gomphus also suggests that this particular species should be moved into its own genus, Turbinellus (as in, Turbinellus floccosus).

Botany resource link: The Rediscovery of One of Canada's Rarest Plants: Yukon draba (Draba yukonensis Porsild), appearing in the latest issue of Botanical Electronic News. “In 2000 a very enthusiastic amateur botanist from New York City decided to come to the southwest Yukon and volunteer to look for plants on behalf of Kluane National Park & Preserve...”.

Brent Hine, curator of the Alpine Garden, constantly experiments with plants thought not to be hardy in the local climate. This approach yields many surprises, but can also lead to a bit of sadness. In the early winter of 2003, it became apparent that this Cootamundra wattle was going to flower prolifically. And flower it did (specimen shot); everyone at the garden talked about this beauty. Fast forward one year to early January 2004, when a night with temperatures dipping to -12.8°C hits. This plant, soon to have masses of flowers again, did not survive. I recall quite a few disappointed faces.

Australia contains nearly one thousand species of Acacia and is the centre of diversity for this genus of about 1350 species. The wattles are emblematic of the country, so you can imagine the concern from Australian botanists when molecular studies suggested that the genus ought to be split up into a number of segregate genera. As proposed, this would have resulted in the majority of Acacia in Australia being transferred into, and forming much (or all?) of, the genus Racosperma. The genus name Acacia would only be retained by those species closely related to the first species to be described under that name (the type species), the African Acacia nilotica (syn. Acacia scorpoides), meaning a reduction in the number of species in Acacia worldwide to 161 species, with only 7 in northern Australia.

To prevent this, a formal proposal was made to the Committee for Spermatophyta under the rules of the International Code of Botanical Nomenclature to switch the type species for the genus to one of the species that would have been transferred to the genus Racosperma – Acacia penninervis. By switching the species which the genus name is based on, the name Acacia would be associated with that particular species and its closest relatives (most of the nearly one thousand Australian species). This proposal was ratified in July of 2005.

If you'd like to read more, here are a few links: The name Acacia retained for Australian species via the Centre for Plant Biodiversity Research; Wattle become of Acacia? from World Wide Wattle; and Orchard, A.E. and Maslin, B.R. 2003. Proposal to conserve the name Acacia (Leguminosae: Mimosoideae) with a conserved type. Taxon. 52(2): 362-363.

Botany / art resource link: A real treat today: the Members' Gallery of the American Society of Botanical Artists shares examples of the creations of approximately two hundred botanical artists in North America. A few of the artists have UBC Botanical Garden connections: Lyn Noble is a UBC Friend of the Garden, Vicki Earle has taught courses here at the garden (I took her botanical drawing class) and Vanessa Pasqualetto is a former technician (we shared an office). I hope I didn't miss anyone else on the list with UBC connections, but I'm sure someone will correct me, if so.

“Powerfully fragrant” is used to describe the scent of this winter-flowering shrub. Selected as a self-pollinated seedling of Daphne bholua 'Gurkha' by Alan Postill of Hillier Nurseries, the name honours his wife – I hope she was very pleased, because this cultivar has since gone on to receive a Royal Horticultural Society Award of Garden Merit.

If the fragrance is so compelling (and it is, in the majority of species in the genus), why are there few Daphne species used in the landscape? Two reasons come to mind from what I've been told: 1) protocols for mass commercial propagation of many Daphne species have yet to be discovered so current production requires labour-intensive processes, and therefore high prices; and 2) susceptibility to fungal pathogens. UBC Botanical Garden and Centre for Plant Research's Dr. Andrew Riseman and his doctoral student, David Noshad, are researching both of these difficulties with an eye to expanding the palette of Daphne species and cultivars available to gardeners. As part of their research, they've sourced a number of difficult to find species of Daphne. Many of these species will eventually form the backbone of the planned Daphne collection in the garden.

For gardening information on 'Jacqueline Postill', you can read this piece from the Royal Horticultural Society: Daphne bholua 'Jacqueline Postill'.

Natural history resource link: The Tucson, Arizona-based The Firefly Forest and companion web site, Wildflowers of Tucson. Firefly Forest was suggested to me by Angus Pratt at the Northern Voice conference, where he and I had a thought-provoking discussion on weblogs being used as natural history journals (with Firefly Forest being a prime example).

A photograph from Eric in San Francisco today, taken in the San Francisco Botanical Garden at Strybing Arboretum (Eric in SF@Flickr | BPotD Flickr Group Pool | original image). I very much appreciate all the photographs of plants I can't find locally - thanks Eric!

The pollen-bearing (male) cones, or microstrobili, of all conifers are very similar in appearance. The female cones (megastrobili) differ morphologically from group to group and can be diagnostic, i.e., they can be used to help identify a conifer while the microstrobili cannot. For a summary of the variability in megastrobili, see conifer cones via Wikipedia.

Podocarpus matudae (no common name that I can find) is native to Mexico, Guatemala and possibly El Salvador (Podocarpus matudae via the Gymnosperm Database). While previously divided into as many as four botanical varieties, the conifer taxonomist Dr. Aljos Farjon, author of the “World Checklist and Bibliography of Conifers”, recognizes only the species.

Photography resource links: Two resources today on the same topic – Digital SLR Infrared by Michael Reichmann of The Luminous Landscape and Digital Infrared Choices by David Burren (if you visit David's site, be sure to browse through either the galleries or the “featured images” pages). When I purchase a new camera, I think I'll convert my current one to IR.

A small scene from the UBC Winter Garden in muted, cool tones; the flowering shrub in the foreground is Rhododendron moupinense, while the conifer is a cultivar of Cupressus arizonica (another cultivar of the same species, 'Blue Ice' was featured two months ago).

Agriculture resource link: Our Vegetable Travelers – “The original publication of Our Vegetable Travelers by Victor R. Boswell appeared in the August, 1949 issue, Volume 96(2) of National Geographic Magazine and is copyrighted by National Geographic Magazine. Reprinted as a special feature in the PLANTanswers section of Aggie Horticulture by permission of the National Geographic Society. February, 2000.” It's important to keep the date it was written in mind when reading about each of the vegetables, as the language occasionally reflects a different era.

Heptacodium is monotypic, with only one species in the genus – seven-son flower. Unknown to Western science prior to 1907, it was encountered by E.H. Wilson during one of his expeditions to China. It remained unknown to Western horticulture until 73 years later when a group of scientists from the Arnold Arboretum and the US National Arboretum collected seed from a cultivated plant in Hangzhou Botanical Garden (the photograph is of a plant grown from one of those seeds). Stephen Spongberg, one of the members of the expedition, notes “...today there are undoubtedly more individual plants in cultivation in North America than in all of China” – you can read more of his recollections on Heptacodium from the expedition here.

The Kemper Center for Home Gardening has extensive photographs of the entire plant, including the flowers: Heptacodium miconioides.

To create this black-and-white, I used some of the Orton Imagery Techniques but did not digitally overexpose the image as suggested. Instead, I only did a 20% screen blend on the duplicate image. From the final image, I chose to use the red channel on its own for the b+w rendition.

Photography resource link: High Dynamic Time Range Images, a new photographic technique developed by local scientist Martin Krzywinski (discovered via The Luminous Landscape) – “Capturing the flow of time in a single frame”.

Today's image was photographed last September in a Venice market by Kimberly T of California (I'm not sure which Venice – California or Italy?). Many thanks, Kimberly!

A top-notch piece of writing on this plant exists online, so rather than trying to retell the story, I'm going to highly recommend you visit this page: Fractal Food: Self-Similarity on the Supermarket Shelf by John Walker, founder of Autodesk, Inc. and co-author of the well-known AutoCAD software. To give a hint of what you'll find on the article, John's divided his (released into the public domain) essay into a few parts: The Unclassifiable Romanesco, A Computational Universe?, Stalking the Vegetable with a Camera and Fixing Fractal Food – perfect Botany Photo of the Day fare.

Conservation resource link: “The Case of the Orchid Smugglers”, an article from Environment Canada's EnviroZine, tells the story of an illegal importation of protected orchids into Canada.

The feature of this rhododendron described by the epithet barbatum is barely discernible in this image. Barbatum translates to “bearded”, and refers to the hairs present on the petioles (the leaf stalks) – if you look closely, you should be able to see a few long hairs on the stalk of the leaf in the lower right.

Rhododendron barbatum is native to the Himalayas; for the taxonomic description, see Rhododendron barbatum in the Flora of China.

Photography resource link: Canon EOS Beginners' Frequently Asked Questions is a comprehensive suite of questions and answers particularly for new users of modern Canon SLR cameras, but much of it is useful for any photographer.

'Blue Streak' violet willow was featured on Botany Photo of the Day ten months ago, so I encourage you to (re)read the entry for Salix acutifolia 'Blue Streak' in early April of 2005.

The species is native to northern Europe and Asia; this cultivar was selected from plants in Russia, apparently sometime in the late 19th century (I haven't confirmed this against a Salix cultivar reference). Like all members of the genus Salix, the bark of the species contains salicin, a chemical from which the medicinal salicylic acid (important in skin care) and acetisalicylic acetylsalicylic acid, or aspirin, can be derived.

Natural history resource link: The Canadian nature observation program, PlantWatch. “The PlantWatch program enables 'citizen scientists' to get involved by recording flowering times for selected plant species and reporting these dates to researchers through the Internet or by mail. When you submit your data electronically, it's added instantly to Web maps showing bloom dates across Canada, so your observations make a difference right away!”

I've been waiting for a few months to feature this photograph from Dr. Chris Wolverton of Ohio Wesleyan University. Chris uploaded it via the BPotD Flickr Group Pool (original image – Chris, let me know if it's not alright that I cropped it). Thanks for sharing the snapshot, Chris – much appreciated!

As to why I held off until today to feature it, the answer is in the specific epithet. This is fruit of the cacao plant; the seeds inside are processed to produce cocoa, cocoa butter and, when the two are combined with varying amounts of other ingredients, chocolate.

Presumed to be native to the equatorial mountainsides of the Andes, Theobroma cacao is now cultivated in many tropical regions of the world. The largest producer is the Ivory Coast, accounting for over 40% of production (but at a cost: see “War Inflates Cocoa Prices but Leaves Africans Poor”, an October 30, 2002 article from the New York Times).

For an excellent overview of the economic botany and history of chocolate, check out Exploratorium's “The Sweet Lure of Chocolate”. And, as always, Purdue University's Center for New Crops and Plant Products also has an informed account: Theobroma cacao.

Photography resource link: Views of the Northeast by Ana Licuanan features several galleries of images from the northeastern US. “Enchanted Forests” contains my favourites, but there are plenty of other gems to be found.

I received a request from a galanthophile to feature a snowdrop on BPotD, so here's one from UBC. The UBC garden has a half-dozen or so different kinds of snowdrops, a number that pales in comparison to the roughly one hundred and sixty different cultivars at Colesbourne Gardens in the UK. With that many cultivars, you might expect a large range of forms and sizes. The reality, though, is that the differences between cultivars can be extremely subtle. The requirement to appreciate detail and subtlety is part of the attraction for galanthophiles.

Snowdrops are native to Europe and Asia Minor. As M.J. Harvey writes in a book review of “The Genus Galanthus” for Botanical Electronic News No. 250, that distribution resulted in a delay in the scientific understanding of the genus. Scientists on one side of the Iron Curtain did not have ready access to the live plants or herbarium specimens from the other side (and vice versa), so no one could compile a complete overview. This changed in the 1990s, facilitating the taxonomic work required for (and subsequent publication of) the monograph of Galanthus reviewed by Harvey.

Botany resource link: A biography of Dr. Katherine Esau, pioneering plant anatomist (yes, she did write the textbook on the subject!). A fascinating story of an accomplished scientist.

A follow-up to the post on Eriophyllum lanatum, these are photographs on the same island by Sheila's friend and co-kayaker, Stephanie Meinke. Thank you, Stephanie!

As Sheila noted to me, these plants were “growing in rocky crevices and depressions wherever a little bit of soil could accumulate”, a similar phenomenon to what was mentioned in this entry on lichen diversity. Over time, most biologically barren surfaces will eventually be colonized by some living pioneers. These pioneers are often (partially) replaced by a succeeding wave of other organisms, which are in turn succeeded by others and so on - a process termed succession. As mentioned by Brent in the comments of the Eriophyllum entry, the nearby Winchelsea Islands sustain a Garry oak woodland community of plants, while these seemingly do not, i.e., the Winchelsea Islands are at a later seral stage (a later stage in the successional process).

Knowing that the Winchelsea Islands are larger in area than the Ada Islands and assuming 1) both groups of islands have the same geological origins and substrate (a fairly safe assumption); 2) the surfaces of both groups of islands have been exposed from the ocean for a similar length of time (a not so safe assumption); and 3) the Winchelsea Islands peak higher than the Ada Islands (could someone please confirm?), what do you think are the factors that have prevented the Ada Islands from going through the successional stages that would allow them to similarly host a Garry oak woodland forest?

A quick note from Olduvai George: Happy Birthday, Charles Darwin.

Photography resource link: While browsing in a bookstore a couple days ago, I was delighted to discover “Tree – A New Vision of the American Forest”, by writer-photographer James Balog. When someone takes an entire day to photograph a tree section by section, you can imagine the result is going to be something spectacular. It is. Site navigation is a bit tricky, but check out the section on Trees – two of my favourites are "Stagg" Giant Sequoia and Sycamore. As an aside, there is no Amazon link because I've decided such a program isn't the right thing for UBC BG in most cases (and I will be removing most of the few existing links to Amazon from the site).

Depending on your perspective, Abeliophyllum distichum is either a rarity or fairly common. If you are familiar with the plant from a horticultural or gardening background, white forsythia is used ornamentally for its spray of white flowers in late winter / early spring (Paghat has a good gardening write-up for white forsythia). However, from a scientific perspective, Abeliophyllum distichum is rare indeed. Restricted to seven known sites in Korea, its future is tenuous. Yong Shik Kim and Mike Maunder have written an excellent account of the species and its history.

Botany / art resource link: If you've some spare time this weekend, you could do worse than spending it on the Rare Books from the Missouri Botanical Garden Library. Also, it's the first time I've seen a garden other than UBC use some of the web-based services or tools available. They've been using del.icio.us to tag the illustrations for annotation and filtering. Oddly enough, I had the same idea for BPotD yesterday after seeing a demo of a soon-to-be-released service while at Northern Voice. I'll add a reminder that I currently use del.icio.us to keep track of all the BPotD resource links.

I mentioned sacrifice in the Eurya japonica entry a couple of days ago. For today's photograph of 'Purple Cape' cauliflower, I had to step into the raised beds in the Food Garden. Thankfully, the smell from the manure applied to the beds wasn't as potent on Thursday as it was when freshly applied on Tuesday (the day I initially sought out the cauliflower for a photograph). I'm trying to recall when Tony Maniezzo (the horticulturist who is responsible for the Food Garden) originally suggested a photograph of this cauliflower. Was it Monday afternoon or was it after the application of manure on Tuesday...?

'Purple Cape' cauliflower is a heritage variety. The country of origin is apparently disputed (either South Africa or Italy), though it was first introduced to England circa 1808.

On the topic of heritage seeds and plants, this year's Seedy Saturday events are starting in communities across Canada (I see my old hometown is holding one tomorrow!). Seedy Saturday is a series of independent public events held for the purposes of swapping heritage seeds (thereby helping to preserve them) and learning about agricultural heritage and biodiversity conservation.

In BPotD news, I'm speaking about Botany Photo of the Day in two upcoming conferences. The first is this Saturday at Northern Voice (held here in Vancouver), where I'm part of a panel on Blogging in Education. The second conference requires a bit more travel: Museums and the Web 2006, being held in Albuquerque from March 22 to 25.

The reason that I mention the latter now is because I'm taking two weeks off on either side of the conference to travel through (and photograph for BPotD) Oregon, California, New Mexico, Utah, Arizona, western Idaho and eastern Washington. I'm planning to leave a lot to fortune on the trip (esp. the weather since the itinerary will be tight); it already looks like I struck out with the desert wildflowers this year. As Phillip mentioned in the BPotD comments recently, there is a record dry spell in Arizona. Despite not having brilliant displays of colour or rain-induced rarities in some places, I'm sure there will be plenty of interesting plants and landscapes along the way. If you have suggestions for (accessible) sites to visit in any of those states, I'd be interested to hear from you. I'll be travelling by car (so no off-roading), but day hikes to exceptional sites are okay.

Photography resource link: For inspiration, Photographs of Lyme Regis, Devon and Dorset by Lois Wakeman – purposefully subtle, yet more compelling for being so.

Thanks to Sheila Williams who sent along this photograph of woolly sunflower. Sheila and a friend kayaked to the Ada Islands last summer (close to the Winchelsea Islands, near Nanaimo, British Columbia). There, they discovered these treasures.

Eriophyllum lanatum also has a more whimsical common name: Oregon sunshine. It is native to western North America, growing from seaside elevations (as seen here) to 3500m (~11500 feet).

The classification of Eriophyllum lanatum and all of its subspecies, varieties and forms has historically been messy – at one time, over seventy-five different names had been applied to what is now roughly recognized as ten morphological varieties. Unfortunately, the need to apply a name to any particular plant masks the biological reality. Eriophyllum lanatum is a species complex – a group of closely-related intergrading taxa.

Species complexes are ideal groups to study the processes of evolution, as the entities involved may be undergoing speciation into distinct entities, i.e., new species. In the intervening time, however, it can be a nightmare to put a name to these intergrading entities; a biological name is intended to represent something that can be clearly delineated, and members of species complexes often defy clear delineation. Still, on the edge of this plant's native distribution where the inflow of new genetic material is restricted by distance, distinct entities can be more easily recognized, hence the assertion that all of British Columbia's plants are of the variety lanatum. At the centre of the range in California, however, things are more complicated. Entities morphologically intergrade and can produce hybrids, though there can be barriers to the latter: see Mooring, J. 2001. Barriers to interbreeding in the Eriophyllum lanatum (Asteraceae, Helenieae) species complex. Am. J. Bot. 88:285-312.

Botany / photography resource link: Photographic Atlas of Plant Anatomy – a compilation of hundreds of categorized plant anatomy images from the research and teaching careers of Dr. John Curtis and Dr. Nels Lersten, with help from Michael Nowak. Even if you don't understand what you are looking at, the images of plant tissue and cells at the microscopic level has a beauty all its own.

Let it never be said that I do not make sacrifices for BPotD. To get this close to a eurya in flower requires setting aside the urge to leave quickly. In the garden's interpretative sign for Eurya japonica, the scent is described as “exceptionally malodorous”. I think I can go one step (but not two) beyond that here – part of the scent is metallic in nature, like that of wet rust or tin. It is safe to assume that the odour of the flowers is the reason for the removal of the eurya growing near the doors of the Shop in the Garden. This was done as part of a recent redesign of the garden's front entrance.

During the process of confirming the family information for this genus, it became apparent that the interpretative sign requires an update. On the sign, the plant is described as a camellia relative – this is now only true in a broad sense. A combination of recent molecular work and a review of the morphological properties has clarified the evolutionary relationships of Eurya, such that placing it in the Theaceae (the tea or camellia family) is no longer supported. Instead, the Pentaphylacaceae is a far better fit. I note with some interest that the Pentaphylacaceae have the familial property of being aluminum accumulators; I wonder if there is a correlation between the scent of the flowers and that property.

Botany resource link: It's been a resource link before, but it certainly deserves the honour of being the first site to receive a second mention – Scott's Botanical Links celebrated ten years of entries yesterday. Since February 7, 1996, Dr. Scott Russell of the University of Oklahoma has been compiling a list of botanical resources on the web. I highly recommend subscribing to the site via email or the RSS feed.

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.

Today's photograph was contributed by Justin of St. Paul, Minnesota (aka teerlinck@Flickr) through the BPotD Flickr Group Pool. The original image is slightly larger, if you'd like to check it out. Thanks for sharing, Justin!

Justin has titled this photograph, “Sego Lilies and Grass in the Badlands”. I think I recognize the grass, but I can't recall its name. There is a grass expert who reads BPotD, so maybe he'll chime in with an identification, unless someone else names it first. The resources I have available to me for grass ID aren't useful, since they don't document the grass at this development stage. As for the sego lilies, not enough details are given to positively identify them either, though I'm fairly certain they are one of Calochortus nuttallii or Calochortus gunnisonii.

As mentioned on the main page of the Badlands National Park web site, the region is extremely important in the understanding of mammalian evolution. It is rich in vertebrate fossils from the Oligocene, the epoch that saw the ancestors of modern mammals rise to dominance among vertebrates. Plant fossils are found, too, though the Denver Museum of Nature and Science suggests that locating plant fossils requires a bit more physical work: Follow a Plant Fossil.

On an opinionated note, I'm pleased to see that the Badland National Park's home page has not been subject to politicization (unlike the main page of a different well-known park famous in understanding geological history).

Environment resource link: Wetlands of International Importance via the Ramsar Convention on Wetlands site. The link contains photographs (of varying quality) and commentary from wetlands around the world – I particularly enjoyed the pages for Laguna Brava (Argentina) and Lac Tsimantampetsotsa, Madagascar.

This sweet-scented, winter-flowering viburnum is not named after the director of a number of Abbott and Costello films. Instead, the name honours a former assistant curator in the Royal Botanic Garden Edinburgh. The Royal Horticultural Society's account for Viburnum ×bodnantense tells the story.

Photography resource link: Subject Matter and Print Size, an essay by Alain Briot for The Luminous Landscape (part of his Reflections on Photography and Art series).

There are roughly one thousand species of Rhododedron in the world. Of these, nearly six hundred can be found in China. Just over four hundred can only be found in China (endemics); Rhododendron ririei is one of the these, native only to the southwestern portion of Sichuan.

Like Rhododendron moupinense, it is one of the earliest flowering rhododendrons locally.

The scientific description is available online from the Flora of China: Rhododendron ririei.

No resource link today – instead, I'll invite you to read the tributes and stories from some of the garden's researchers, staff and Friends of the Garden for the recently deceased Christopher Lloyd of Great Dixter: Christopher Lloyd (Christo) 1921-2006.

Eric in San Francisco (Eric in SF@Flickr) shares another image today, via BPotD Flickr Group Pool (original image). As I mentioned previously, Eric has many, many plant photographs on Flickr. Be sure to browse through his image sets, if you haven't already. Thanks again, Eric!

Plukenet's heath was named by Linnaeus in honour of Leonard Plukenet (text-only - images on page are broken), a British botanist who died the year before Linnaeus was born. Erica plukenetii is native to the Cape region of South Africa.

As mentioned previously on BPotD, the Cape Floristic Region of South Africa is a biodiversity hotspot. For the genus Erica, South Africa is very hot – over 650 species according to the Biodiversity Hotspots site! To put that in perspective for local readers, all of British Columbia contains (very) roughly 3200 species of vascular plants. As an aside, does anyone want to take a guess as to which genus in British Columbia has the most species? I have a suspicion that it'd be the same genus for most Canadian provinces and northern US states.

For those interested in heathers, there are very active heather clubs around the globe, such as The Heather Society (UK) and The North American Heather Society.

Photography resource link: For inspiration and interest, the photography of Janet Davis. Janet is a Canadian-based garden writer and photographer and a good friend of UBC garden's David Tarrant. Her site, Beautiful Botany, also contains samples of her garden writing.

If you had trouble accessing the site yesterday, it was because of some flakiness in the connection between the university and the rest of the world that affected both incoming and outgoing communications. I hope you weren't inconvenienced too much.

I doubt this photograph would win any awards for technical composition. However, I think the subject is a good companion to yesterday's image with its similar shapes and patterns, so that's why it's posted. I should mention (full disclosure!) that I cloned out a distracting branch with catkins in the lower left.

Black willow or black pussy willow is a dark-bracted variant of rosegold pussy willow, Salix gracilistyla. The species is native to east Asia, but this particular cultivar has its origins in the gardens of Japan. To read more, Paghat has an excellent account about it: Salix gracilistyla 'Melanostachys'. You'll note that on her site (and in many other places), Salix gracilistyla var. melanostachys is used; I'm speculating, but I suspect that when this plant was first described by scientists, its garden origin was not known and so was thought to be a naturally-occurring variety (hence var. melanostachys). When it was determined to be of cultivated origin, the scientific name could no longer apply, hence the transformation to a cultivar name, 'Melanostachys'.

In other news, I submitted the BPotD entry on Taxodium distichum to the latest issue of the Tangled Bank (#46). If you'd like to read some of the best science weblog writing on the web or discover other science-themed weblogs, the Tangled Bank is for you!

Natural history resource link: I had reason to visit the web site of the Natural History Museum in London, England yesterday, and was quite impressed – much to explore (don't miss the “Nature Online” section) and it is presented crisply.

Let's start February with one of my favourite photographs; coincidentally, it is also a personal favourite plant: Camellia transnokoensis. I don't think there's a common name for it in English, though Mount Noko camellia has a pleasant fluidity when spoken. The epithet transnokoensis means “of across Noko”, alluding to a native distribution across Mt. Noko of Taiwan.

January in Vancouver has been extremely wet this year, including a stretch of weeks with daily precipitation that missed the record of consecutive days of rainfall by mere hours. I haven't therefore had much opportunity to take photographs. When I did attempt some picture-taking on January 26, I noted that this camellia's first flower of the year had opened. This photograph, however, is from last February in the David C. Lam Asian Garden.

For photographs of the plant in flower and habit, you can see the thread on the garden's discussion forums from late March 2003: Camellia transnokoensis. There are not too many other images available online of this rare-in-cultivation plant.

Photography resource link: Woodsong Nature Photography is the site of Cindy Mead, who also happens to be a frequent contributor at Nature Photographers Online. You might recall the Orton imagery technique I used in a BPotD entry last month. Cindy is also a fan of the technique, and has an entire gallery of Orton Method Imagery. She also has a weblog, WoodSong.