Thank you to Barbara (aka Monceau@Flickr | BPotD Flickr Group Pool | original image) for this photograph of a milkweed taken in Pennsylvania last summer.

Asclepias syriaca, or common milkweed, is widespread throughout eastern and central North America. It is often considered a weed due to its economic impact on crops and toxicity to livestock, but monarch caterpillars consider it otherwise (monarchs feed exclusively on Asclepias spp.). To read more about Asclepias syriaca, Missouri Plants has a good summary, while Purdue University's Center for New Crops and Plant Products discusses its (potential) economic value.

Botany resource link: All of the vascular plants of Antarctica on one web page, by the British Antarctic Survey.

Like Lantana camara, the native distribution of Chinese fir is not known; however, it is for a different reason. An important timber tree in southeast Asia, Cunninghamia lanceolata has been cultivated for its wood for over eight hundred years. It is now nigh impossible to determine where it is native and where it has been introduced.

Its importance as a timber tree is at least partly due to both the ease in which it can be propagated clonally and its ability to regrow from its roots – both qualities which are rare (unique?) among conifers (source: Minghe L and G Ritchie. 1999. Eight hundred years of clonal forestry in China: I. traditional afforestation with Chinese fir (Cunninghamia lanceolata (Lamb.) Hook.). New Forests. 18(2): 131-142).

'Glauca' refers to the bluish-grey waxy “bloom” of the new foliage.

As always for conifers, also see Cunninghamia lanceolata via the Gymnosperm Database.

Photography / art / nature resource link: It's not botanical, but I'll make an exception for it, since the artist's message is profound. Thanks to Eva for sending along this gem: Ashes and Snow. “Gregory Colbert's Ashes and Snow is an ongoing project that weaves together photographic works, three 35mm films, art installations and a novel in letters. With profound patience and an unswerving commitment to the expressive and artistic nature of animals, he has captured extraordinary, unscripted interactions between humans and animals.” Grist has an article about the exhibition in Santa Monica.

The last milestone before BPotD's one year anniversary, this is entry number three hundred.

An alpine plant native to western North America, pygmy bitterroot is found at elevations of 2300m to 4200m in the mountains stretching from California north to British Columbia, with disjunct populations in Yukon and (in some references) Alaska (distribution map). In the book The Genus Lewisia, Brian Mathew comments that “this species presents us with perhaps one of the most tricky taxonomic problems in the genus Lewisia for it is extremely widespread and variable and there is apparent pattern to the variation.” Mathew goes on to describe a half-dozen geographic variants, generally at the southern extreme of its range. Some of these variants are reflected in the Flora of North America description for the species. For an online horticultural account of Lewisia pygmaea, visit the North American Rock Garden Society's site.

This photograph was taken in late May of 2004 at the University of Alberta's Devonian Botanic Garden, where I had a highly enjoyable visit (and so should you if you are ever in Edmonton).

Botany resource link: Scott's Botanical Links recently featured ALGAL-ED, a site with a goal “to provide educational tools for the student interested in learning about freshwater algae”. The site includes images and movies – yes, movies of algae! Check out Chlamydomonas as an example of a motile green alga.

Guestblogging today is UBC Botanical Garden and Centre for Plant Research's data technician, Eric La Fountaine. Eric also scanned these seeds. – Daniel.

Although they look somewhat like deep sea creatures, the objects in this scan from the John Davidson Seed Collection at UBC Botanical Garden are the seeds of a popular garden annual, Centaurea cyanus. Its common names include bachelor's button and cornflower. This species easily escapes from gardens and is a widely spread naturalized weed in North America, to the point of being classified as an invasive in some jurisdictions. However, in the United Kingdom where it reaches the northern limits of its native distribution, the species is considered endangered!

For photographs of the flower, see Centaurea via the site of Andrea and Friedrich A. Lohmüller.

Photography resource link (by Daniel): For inspiration, the landscape photography of Leping Zha. Of his several galleries, my favourite is Nature's Melody. Discovered via Metafilter.

Alejandro, aka janrito@Flickr, shares his photograph of platanos cultivated in Ecuador with us today (via the BPotD Flickr Group Pool | original image). Many thanks, Alejandro!

Edible plants generally have good sources of information online, and the banana is no exception. I'll step aside today and guide you to two excellent references: for a quick overview, read Musa from Cornell University; if you'd like to read about bananas in detail, spend some time on Mark Rieger's Banana and Plantain page, part of his comprehensive Fruit Crops site.

From what little I know of identifying bananas, I think it'd be particularly difficult (if not outright impossible) to pin down the precise name of this banana from the photograph. Examining Mark Rieger's site suggests that some crucial missing pieces of information include the sweetness of the banana and the thickness of the berry's skin. At the very least, it is certainly something of hybrid origin and cultivated – the native distribution of edible Musa species is southeastern Asia to northern Australia.

Agriculture / conservation resource link: Saving the Bottle Gourd from the New Agriculturist; Lagenaria siceraria is estimated to have been in cultivation for over ten thousand years, but indigenous knowledge of the plants is being lost with the use of plastic containers and changing diets. How to stop the loss? A Gourd Museum. Discovered via the IPGRI Public Awareness weblog – listen to an interview with people involved in creating the Gourd Museum here.

Alternating veins of wax and chlorophyllic bark suggest this maple is a member of the section Macrantha, or snake bark maples (a section is a grouping of closely-related species within a genus). In this instance, it is indeed a snake bark: Acer tegmentosum, the Manchurian stripebark maple or Manchu striped maple.

Douglas Justice writes in Snake Bark Maples at UBC Botanical Garden (PDF from the Davidsonia):

“The most recognizable feature of the snake barks is their attractive stems. Stem striping is due to waxes that are produced and accumulate in the longitudinal fissures of the expanding bark (Oterdoom & De Jong, 1994). While the most common species exhibit strikingly striped stems, not all species do. To complicate matters, a few maples belonging to other groups have striped bark, particularly in youth; e.g., some forms of A. stachyophyllum (Section Glabra). ... On most species [of snake barks], the most obvious stripes occur on young shoots and gradually disappear as the outer bark becomes increasingly corky on older stems. ... Some stem shading is usually necessary to prolong the life of both bark stripes and the photosynthetic capacity of the stems, although this varies considerably between species and among individuals.”

This particular plant is growing in moderate shade. Photographed here is the main trunk of a twenty year old tree, at approx. 2m from the ground. I chose to retain the natural angle of the trunk for this photograph, instead of adjusting the stripes to be vertical or nearly so like they would normally appear on a trunk perpendicular to the horizon.

Photography resource link: Landscape Photography Composition (part I), an article by Guy Tal for Nature Photographers Online. Know the rules, break the rules.

This image of a South African plant growing in a South American botanical garden is courtesy of Andreas of Bogotá, Colombia (aka Quimbaya@Flickr | BPotD Flickr Group Pool | original image). Thank you again, Andreas!

Plumbago auriculata is also widely known as Plumbago capensis, a name used so often that it is even reflected in one of this species' common names: Cape plumbago. Other common names include Cape leadwort and blue plumbago.

The confusion over the scientific name is explained by Alice Aubrey of Africa's Witwatersrand National Botanical Garden in her account of Plumbago auriculata. In brief, Plumbago auriculata was named in 1786 by Lamarck from cultivated plants in the East Indies. Eight years later, Thunberg assigned the name Plumbago capensis from specimens collected from its native home in South Africa – it was this latter name that caught on and became commonly used. However, since Plumbago auriculata is the earlier published name, the botanical rules of nomenclature suggest giving credit where it's due, hence Plumbago auriculata should be used. I think the difference between this scenario and the story behind Thujopsis / Dolophyllum is the era in which the “clerical” error was discovered – in recent years, conserving long-standing names occurs fairly often when a name change would generally be required for a technical reason.

The botanical garden in Colombia where this picture was taken, the Jardín Botánico José Celestino Mutis, is named in honour of a prominent Spanish botanist. Read more about José Mutis via the Encyclopedia Brittanica Online. “His Flora de Bogotá o de Nueva Granada, containing more than 6,000 illustrations, was so massive that the Spanish government could not afford to print it.”

Conservation resource link: Julie, writer of the Human Flower Project weblog, has an entry on Penstemon grahamii. It has long been argued that Graham's beardstongue should receive some legal protection due to its rarity (less than 10 000 individuals exist). The need for protection has become yet more critical with recent proposals to explore and extract oil from the oil shale substrate on which Penstemon grahamii grows. If you are a United States citizen, you can help if you so choose – public comments are invited.

Brent Hine only recently planted this spurge in 2005, so I've yet to see and smell its flowers. I'm particularly anticipating the fragrance. If you're familiar with the common name for another organism, Apis mellifera, you can likely guess that the flowers are honey-scented. This photograph shows the other reason it is popular in gardens – its foliage. Indeed, garden designer Mary Newstead gives it high praise: “arguably the finest member of the Euphorbia family”.

Often cited as being native to the Canary Islands (which it is), honey spurge can also be found in the Madeira Islands. If my translation of Portuguese is correct, in the Funchal Ecological Park of Madeira Island, it grows as an understory shrub or small tree. In colder temperate climes, though, it grows as a small shrub or shrubby perennial.

Botany / science resource link: Electronic Sites of Leading Botany, Plant Biology and Science Journals links to the web sites of nearly one thousand scientific journals. A quick browse of the list reveals the depth and breadth of botany sensu lato (in the broad sense).

John Davidson took this photograph of oak mazegill, sometime in the early 20th century.

Daedalea quercina is an inedible fungus native to North America and Europe. It is found almost exclusively on oaks (the genus Quercus), hence the epithet quercina. Associated with brown rot in the wood of oaks, arborists need to be able to identify this and other types of wood decay fungi to assess urban trees for weakening.

The name Daedalea is a reference to Daedalus, the labyrinth-maker of myth (built for the minotaur). Similarly, the maze-like pattern of pores is taxonomically described as being daedaloid.

Photography resource link: Conservation Photography - Art Born of Environmental Ethic, an article by Cristina Mittermeier for NatureScapes.net. It relays the story of Peter Dombrovskis, whose photography helped prevent the damming of the Franklin River in Tasmania (visit both the cross-section and posters sections of that site to see examples of this late photographer's work).

Hiba arborvitae is native to Japan. According to the Great Plant Picks profile for Thujopsis dolabrata (PDF), it also has two other common names, both inspired by the shape of the scale-like leaves: deerhorn cedar and battle axe cedar.

The Gymnosperm Database entry for this monotypic genus, Thujopsis, imparts a story about how the genus should technically have a different name, since it was earlier named Dolophyllum. However, the taxonomists Farjon and Hunt suggest that the old name be kept, since all publications since 1844 have used the name Thujopsis.

Natural history resource link: I thought you might like a peek at one of my inspirations from the nature and science perspective (since I usually mention photographers who inspire me). Natural History at Ragged Chutes contains photographs and notes from a field trip led by my uncle along the Mississippi River of Lanark County, Ontario. If you read through to the last page, you'll get a glimpse of an ethic he instills in others – leave a natural place cleaner than you found it.

The autumn colour of smooth sumac displayed via a scan, by Maureen from Montana, aka MontanaRaven@Flickr (BPotD Flickr Group Pool | original image). Many thanks again, Maureen.

Smooth sumac is distributed throughout the continental United States and overflows into both southern Canada and northern Mexico. In a photograph by Hugh Iltis on the Robert W. Freckmann Herbarium's page for Rhus glabra, you can see evidence of its ability to propagate vegetatively, allowing it to form a contiguous mass of clonal plants. The Virginia Tech Forestry Department also has a series of photographs for smooth sumac that are worth investigating.

Photography resource link: Levels of Abstraction – Are Your Photographs Real?, an essay by Michael Reichmann of The Luminous Landscape. “For some reason there are photographers who believe that photographs and the real world have more than a passing relationship to each other. When they see a photograph that has been in some visible way altered, modified or manipulated they cry "foul" – taking on the mantle of protectors of the sanctity of the inviolate image.”

Spanish fir or hedgehog fir is native to only a small corner of southwestern Spain. Hedgehog fir is an adequate description – the short, blunt needles of nearly equal length stand out as a feature of this conifer (Abies pinsapo from this page (warning: image-heavy)). Since today's image is a bit on the abstract side, you might also like to investigate a few other photographs of Abies pinsapo from this article in the Davidsonia on the Silver Firs in UBC Botanical Garden (PDF). I'm still working on the new Davidsonia site, so I won't link there directly.

As always for conifers, it is worthwhile to check out the entry in the Gymnosperm Database: Abies pinsapo.

For the black-and-white image, I've used the technique outlined here, with an initial green-blue screen at 100%, then an alpha1-red multiply.

In other news, here's a contest for you! If you're a long-time reader of BPotD, you'll certainly recall the entry on David Bookbinder's Flower Mandalas. The Science Creative Quarterly (about the SCQ - note that it's also a UBC project!) is collaborating with David to hold a contest using the flower mandalas as inspiration.

“The SCQ is pleased to present a contest that seeks “creative” entries inspired by the photographic images found in David Bookbinder’s Flower Mandalas Project. These creative pieces can be composed to the whim of the author, in any form including (but not limited to) poetry, fiction, and/or personal essay; and should preferably refer to a specific flower image found either here or at the main website.”

For all the details, see A Year of Flora: The Flower Mandala Contest. Good luck!

This also reminds me that this BPotD contest is yet to have a winner...

Horticulture / environment resource link: I'll start with a note of thanks to both Beverley for taking the time every day to source zone information for the gardeners who visit the site and to the others who comment on their real world experiences with the published figures. For a detailed look at the USDA Plant Hardiness Zone map, how it has changed in fourteen years and some of the impacts of a changing climate, read “Going to Extremes”, an article by Chris Clarke of the Creek Running North weblog.

Rhododendron moupinense is one of the earliest flowering rhododendrons locally. Its delicate flowers are susceptible to hard rains, so a late January or February storm can leave this plant (specimen image) looking as if someone emptied a swimming pool onto it all at once.

Although some sites give it a common name of dwarf rhododendron, that name is applied to so many rhododendrons as to be functionally useless. Moupin rhododendron would be a better choice, referring to its occurrence in a mountainous region in Sichuan, China. Another alternative would be Baoxing rhododendron, as Baoxing County is the modern name for Moupin. This area of China, near the Tibet border, is famously known as the area where the European missionary and naturalist, Père Armand David, first encountered the (skin of a) giant panda. Incidentally, Rhododendron moupinense was named and described from specimens collected by David.

For a taxonomic description, see the Flora of China account for Rhododendron moupinense.

Botany / mycology resource link: Rogers Mushrooms by noted British author Roger Phillips. Geared toward North American and European mushrooms, the site includes identification keys, photographs and recipes for you mushroom aficionados.

Sixth in a series featuring photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. Again, an image by David Tarrant from a November venture to New Zealand. – Daniel

For this plant, David noted: “This photograph was taken in an outstanding new bed on the north slope of the Larnach Castle grounds. Larnach Castle is located on the Otago Peninsula of New Zealand's South Island.”

There are thirty-nine or so species in the genus Aciphylla, and from this image alone it is impossible to be certain of its identity. Douglas Justice and David have tentatively identified it as Aciphylla squarrosa, one of the most common species in cultivation.

Common names for Aciphylla squarrosa include taramea, speargrass, and my favourite, common Spaniard. To understand the latter, you'll need to recall that when these plants were first learned of by European explorers, the Spanish were associated with swords. The resemblance of the sharp, long leaves and bracts to the Spanish weapons doesn't require too much lateral thinking.

Plants for a Future Database's entry on Aciphylla squarrosa includes references that suggest the cooked root is edible – perhaps not surprising, as it is related to carrots and parsnips. Using other plants in a family as a guide to determine potential edibility is not advised, though. After all, all three are also related to the deadly poison hemlock.

Photography resource link: There is much to like about the work of Daniella T. from California – I particularly like the images from Joshua Tree National Park and Sequoia National Park in Winter.

Number five in a series featuring photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. Like yesterday's photograph, this image is by David Tarrant, UBC BGCPR's Public Relations and Programs Coordinator, from a recent trip to New Zealand. – Daniel

In his notes to me for this entry, David wrote, “These cypress knees were taken in Ayrlies, the amazing garden of Beverley McConnell. The garden is located in Whitford, just south of Auckland.”

Unlike yesterday's and tomorrow's plants, bald cypress is not a native to New Zealand. Taxodium distichum is instead native to the southeastern United States, Mexico and Guatemala, but is also widely cultivated.

Why do the roots form knees? Despite speculation that the knees help provide oxygen to the roots in water-saturated soils, no physiological function has yet been determined (source: the “Silvics of North America” account for Taxodium distichum). Knees of mangrove trees, however, do promote the diffusion of oxygen into the roots. What's the difference? Mangrove roots forming knees have lenticels, recently discussed in the BPotD entry on Prunus serrula. Taxodium distichum? No lenticels.

For more on this beautiful tree (including photographs), see Taxodium distichum via the Gymnosperm Database on conifers.org.

Botany resource link: About Plant Physiological Ecology (an introduction to the topic) – “The problem of how plants can grow in places representing severely unfavorable climate conditions and growth substrates is central to physiological ecology.”

Fourth in a series featuring photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. David Tarrant, UBC BGCPR's Public Relations and Programs Coordinator, took this photograph on a recent trip to New Zealand. – Daniel

David took this photograph in Te Kianga Marire private garden. In David's words, “This entire garden is exquisitely landscaped with New Zealand native plants.”

Commonly known as “Poor Knights lily”, Xeronema callistemon and the related Xeronema moorei are the only two members of the plant family Xeronemataceae. This plant was first discovered in 1924 on inland cliffs of the Poor Knights Islands, and later also found on the island Taranga (Xeronema moorei is native to New Caledonia, 1500 km to the northwest).

Xeronema callistemon is considered a threatened plant in New Zealand, because of the extremely restricted range. However, because of its attractive inflorescence, it is becoming more common in cultivation. Two forms are taxonomically recognized: the typical Xeronema callistemon f. callistemon and the minor genetic variant, Xeronema callistemon f. bracteosa (links contain photographs and descriptions of both via the New Zealand Plant Conservation Network).

Photography resource link: For inspiration, the photography of Oregon's Zack Schnepf.

Third in a series featuring photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. Today's photographs and comments are by Peter Wharton, Curator of the David C. Lam Asian Garden. – Daniel

View Part I here – NB: I mixed up the slide numbers so part I now has a different photograph!

... As generations pass, tree weight and windstorms increasingly cause individuals to assume prone positions, yet live on (today's photograph 1). These trees still thrive as their root systems remain undamaged, no doubt assisted by their renowned, flexible wood. If they fall across a ravine, their upper branchlets can take root on the opposite bank, thus the mother tree can in a sense move laterally! In many cases these prone “bridge trees” form vertical “stockades” of young growth along their upper trunks, from crown tip to root crown. This I have seen in the numerous gills or steep sided ravines that are a feature of this area. The final photograph (today's photo 2) shows a history of a mother tree, a falling event (or rooting lateral branch) and resumption of reiterative vertical growth. The vegetative propagative attributes of this species, on unstable bedrock, has helped sustain this tree in a region that is still too cool to allow reliable seedling regeneration. Our warming earth could of course change this situation rather soon.

The age of these specimens on Castle Hill Wood appear to range from 400 to 800 years, with a few no doubt approaching a 1000 years. Recent work in southern Britain is indicating that old coppiced specimens may live as long as several thousand years – competition for the English yew (Taxus baccata). It is gratifying to see the obvious improvements in ancient woodland conservation management in areas I knew as a boy. For instance, the retention of stumps, snags and fallen logs is the norm in British native woodlands.

Those wanting more information on veteran trees should investigate English Nature's Veteran Trees Management Handbook or The Future for Veteran Trees (PDF).

The extensive groundcover in the photos above is dog's mercury (Mercurialis perennis). This area is also home to a host of interesting British herbaceous natives, including ramsons (Allium ursinum), giant bellflower (Campanula latifolia), lady's slipper orchid (Cypripedium calceolus) – which my father saw on his honeymoon 56 years ago! –, daffodil (Narcissus pseudonarcissus) and Herb Paris (Paris quadrifolia).

Science resource link by Daniel: ScienceBlogs – “features blogs from a wide array of scientific disciplines... It is a global, digital science salon.”

Second in a series featuring photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. Today's photographs and comments are by Peter Wharton, Curator of the David C. Lam Asian Garden. – Daniel

Updated Jan. 15, 2006 – I had the slide numbers mixed up, so there's a new photograph 1!

The small-leaved lime or linden (Tilia cordata) has a very scattered distribution in the United Kingdom and is often associated with limestone bedrock, where rocky bluffs or ravines provide a refuge for this species and associated calciphilic vegetation. Anyone wanting a detailed survey of this species in the U.K. should consult the encyclopedic lifework of Dr. Richard Mabey, Flora Britannica.

My father, a retired medical doctor, has spent much time rambling through the North Yorkshire Moors exploring the many fragmentary ancient woodlands that are a feature of steep sided river valleys which radiate from the moors. While on holiday last summer, my father directed me to a remarkable woodland dominated by impressive, ancient specimens of the small-leaved lime or linden, with a wonderfully rich herbaceous vegetation to match. Castle Hill Wood is underlain by Upper Jurassic Corallian Limestone and it forms a significant outlier from the surrounding Hambleton Hills, just south of the moors and near the market town of Helmsley. The river Rye and Rievaulx Abbey, a ruined Cistercian order monastery lies below, completing this aesthetic palette.

Castle Hill Wood is nationally classified as a “Site of Special Scientific Interest” and now receives appropriate protection. The veteran, semi-prone, ribbed trees pictured here present to the viewer a history of fortitude and longevity. My wife, Sarah, and I climbed through this wood in growing wonder as huge old hulks of the common oak (Quercus robur) and increasingly, our primeval linden friends enclosed us. In early summer these woods must glow bright yellow from the linden flowers, no doubt accompanied by the hum of innumerable bees. As normal upstanding trees or as multistemmed specimens they become increasingly fluted with age (photograph 1). With time they become increasingly prone to windfall on these thin soiled sites with a naturally fractured bedrock. As generations pass, tree weight and windstorms increasingly cause individuals to assume prone positions, yet live on... (photograph 2)

To be concluded in tomorrow's entry!

Photography resource link (by Daniel): Tripods 101 – a guide to understanding tripods and what to consider if you plan to purchase one. Very timely for me, as I'm very close to needing a new one.

The next few days will feature photographs and writings from other staff and researchers at UBC Botanical Garden and Centre for Plant Research. To start the series, photographs from the Galapagos Islands and comment by Dr. Quentin Cronk, the garden and research centre's director. – Daniel

Darwin's cotton, photographed near Urbina Bay of Isabella Island. Although this cotton is endemic to the Galapagos Islands, it is closely related to Gossypium barbadense, or Egyptian cotton. See: Wendel, J. F. and R. G. Percy, 1990. Allozyme diversity and introgression in the Galapagos Islands endemic Gossypium darwinii and its relationship to continental Gossypium barbadense. Biochemical Systematics and Ecology 18:517-528.

Daniel adds: Dr. Keith Adams from the UBC Centre for Plant Research uses Gossypium to understand the evolution, expression and function of duplicated genes.

Conservation resource link (by Daniel): The Charles Darwin Foundation “exists to provide knowledge and support to ensure the conservation of the environment and biodiversity of the Galapagos Archipelago through scientific research and complementary actions.”

Dale submitted this thistle image taken in Carmel Highlands, California (Dfunk@Flickr | BPotD Flickr Group Pool | original image). Many thanks again, Dale!

There have been a few BPotD entries where the plant's scientific name is apparently duplicated. Does the duplication of an epithet (e.g., var. occidentale) add extra information? Yes! Without knowing anything else about this taxon, it gives two additional pieces of info:

• this was (almost certainly) the plant first described by a taxonomist as representative of the species. Often, but by no means always, this also represents the most common biological form, based on the notion that the most common taxa within a species will often have been collected and described first.
• there is at least one other biological entity recognized at the same level. In the case of Cirsium occidentale, there are at least four varieties recognized.

The duplication of epithets occurs from a practical and use perspective when a taxonomist makes an evidence-based decision to split up a species into taxa below the rank of species, i.e., subspecies, varieties or forms (note: contemporary requirements include also that the evidence and rationale must be published in a peer-reviewed scientific journal). As soon as one of these infraspecific taxa is carved off from what was once a singular species, the remainder of the species gets tagged with the duplicate name to differentiate it from the new entity. I'll give a hypothetical example. Say there was a species named Aa ee and someone came along and said, “This part of that species is different.”, I'll publish it as Aa ee var. ii – it is now necessary that the remainder of the original grouping have a name that can be used to communicate about it separately, i.e., Aa ee var. ee. The entire species, including all of its varieties, can still be discussed by using Aa ee. For a shorter version of what I just wrote, see Article 25 of the International Code of Botanical Nomenclature.

For the purposes of this cobweb thistle, knowledge of the reasoning for the name is required to understand its distribution. The entire species Cirsium occidentale has a distribution that includes Oregon, California and (possibly) northwest Mexico. However, Cirsium occidentale var. occidentale is native only to California.

Photography resource link: To my mind, one of the best contemporary nature photographers rarely has nature in his images. He is one of the few whose every image provokes an emotional response in me. Edward Burtynsky. (Oil fields No. 1 | C.N. track No. 8 | Rock of Ages No. 7 | Three Gorges Dam Project, Feng Jie No. 6)

Chinese witchhazel is native to southeastern China. Its family, the Hamamelidaceae or witchhazel family, has a curious distribution from a biogeographic viewpoint (map). If you're a long-time BPotD reader, you'll remember that the biogeographical link between plant families of southeast Asia and North America is well-established (see this entry). The distribution across southern Asia into Europe is also understood (and easy enough to imagine). However, the presence of the family in southeastern Africa and Madagascar is a bit of a headscratcher to me. While digging around, I reviewed the paper from the entry on another hamamelid, Disanthus cercidifolius (Li et al. 1999. Phylogenetic relationships of the Hamamelidaceae inferred from sequences of internal transcribed spacers (ITS) of nuclear ribosomal DNA. Am. J. Bot. 86:1027-1037). As it turns out, there is not enough evidence (yet) to clearly understand the biogeography of southern hemisphere Hamamelidaceae, so it remains a puzzle for now.

Two other links to add: 1) Hamamelis mollis interpretative sign at UBC Botanical Garden; and 2) Great Plant Picks shrub selections, which include a link to a PDF profile about this plant.

Botany resource link: The Parasitic Plant Connection by Dr. Dan Nickrent of Southern Illinois University. Scroll down the page for links to pages on parasitic plant families.

Today's image is courtesy of Angie from St. Paul, Minnesota (Angie in MN@Flickr | BPotD Flickr Group Pool | original image), who previously submitted Omphalotus illudens. Thanks again, Angie!

This organism has a number of common names: sulfur shelf, sulfur polypore, chicken of the woods and, by a handful of people, tree brain (though this common name is more often associated with Peniophora rufa).

The name Laetiporus sulphureus was previously applied to a wide-ranging North American species that grew on a variety of substrates. Upon further examination, however, fungal taxonomists have split up the old Laetiporus sulphureus into a number of separate species. The current Laetiporus sulphureus, pictured here, is native to eastern North America and grows on (in) hardwoods. To give an example of one species that has been split off, Laetiporus conifericola is native to western North America and grows on conifers. Tom Volk tells the story in his page on Laetiporus cincinnatus. He also discusses the common name “chicken of the woods”, which apparently is how it tastes when cooked properly, though I haven't tried it.

Photography resource link: Macro Art in Nature is a macro photography weblog by Michael Brown of South Carolina. His abstracts are worth your time to investigate. Michael posted a couple comments to BPotD yesterday, which was a bit of a coincidence – without any correspondence between us, I had planned to suggest his site as today's resource link.

Photographs of the peeling bark of paperbark cherry (or Tibetan cherry or birch cherry) are fairly standard fare for winter articles in gardening magazines and web sites, so I thought I'd create a second, and fanciful, version using a technique similar to yesterday's Orton Imagery for a different take.

The horizontal yellowish blisters are lenticels. These fractures in the cork layer of the bark allow the diffusion of gases (particularly oxygen) into the metabolically active cells beneath the bark surface. For microscopic cross-sections of a lenticel, see here or here – note that these are from much smaller (and longitudinal) lenticels.

For the second image, I used the Calculations command and did a red-red color burn with result on "New Document". With the new black-and-white image (which I also find compelling), I first changed the image mode to greyscale. Then, following the same process as the latter parts of the Orton Imagery technique, I moved the image as a new layer onto the original image, and blended the layers using luminosity at 84%.

Horticulture / landscaping resource link: PlantAmnesty, whose mission is to “end the senseless torture and mutilation of trees and shrubs”.

Today's images are a follow-up to the December 22, 2005 entry for Garrya ×issaquahensis 'Pat Ballard'. I thought I should have a photograph of the flowers in full bloom as an accompaniment. The previous entry has some links about the plant from both botanical and horticultural perspectives, so I won't add more for this entry.

Photography / art resource link: If you're curious about the second image, I've used what Darwin Wiggett has called “Orton Imagery”. For a step by step guide on how to accomplish this with both film and digital images, Darwin has written “Orton Imagery – A How To Guide for Photographers via Nature Photographers Online. You can also check the Orton in Orton Imagery here: Michael Orton Photography.

Today's entry was contributed by Tamar Yadin of Israel, whose brother Ofir sent it along as a suggestion. Tamar is quite the creative person, with a real eye for design – her web site (currently only works in Internet Explorer) showcases her photographs and other works. Thank you, Tamar (and Ofir!).

Known commonly as poppy anemone, windflower or crown anemone, Anemone coronaria is native to the Mediterranean. Tamar and Ofir both communicated to me that the wild populations of this anemone are on the decline in Israel due to increasing urbanization and agriculture; populations of it are now found mainly in the north of the country, near Galilee. Tamar also added that it is now a protected plant in Israel.

The colour of flowers in wild plants of the species is highly variable, ranging from white and pink through red and purple to blue (Google image search for A. coronaria). Whenever you see an attractive flowers with variability, you can be near certain that generations of domestication (i.e., plant breeding) will have produced a number of cultivars as a general rule. Anemone coronaria is no exception. As an example, Anemone coronaria [De Caen Group] is a popular group of hybrids originally bred in France.

Photography resource link: New Year's Resolutions for Photographers care of Bob Johnson at Earthbound Light. Bob also has oodles of other photography tips. Discovered via the weblog static photography.

An uncommon plant today, I suppose; there's not a single image in Google's image search for this species!

Andy Hill, one of the garden's horticulturists, walked into my office as I was prepping this photograph for BPotD and exclaimed, “Oh, Zanthoxylum. That's fun to prune...not.” This climbing shrub gets my vote as the most “vicious-looking” plant in the Asian Garden, and from what I understand from Andy, doesn't just look vicious – it is vicious. To give an idea of scale, this section of the stem near the base of the shrub is about as thick as a baseball bat (a little below 7 cm in diameter).

Zanthoxylum is a member of the citrus family, the Rutaceae, so its relations include oranges, lemons and limes. However, instead of a hesperidium, the fruit of Zanthoxylum is a small, single-seeded capsule. I like to pinch these between the tips of my fingers and then enjoy the scent, which certainly has elements of citrus in it.

This particular plant was grown from seed collected by Keith Rushforth, plant explorer and author. Keith obtained the seed near the village of Chendebji in Bhutan at 2500m / 8200'. If you are interested in seeing the landscape of the area, perhaps the film “Travellers and Magicians” might appeal – I haven't seen the movie, but most of the villagers of Chendebji appear in it!

A few more photographs of it on the garden forums: Zanthoxylum oxyphyllum.

Science / conservation resource link: Mangroves, Fishponds, and the Quest for Sustainability, an essay by scientist Dr. Jurgenne H. Primavera of the Phillippines. “We scientists in developing countries need to come down from the Ivory Tower and disseminate results not only in peer-reviewed journals but also through advocacy and the popular media. We must not forget our hearts even as we apply our minds. We do science not in a vacuum but against the grinding poverty and environment-unfriendly character of modern times, and we can use our scientific knowledge to reduce suffering and make life more full for fellow humans and creatures.”. Discovered via Science Matters, an article by Dr. David Suzuki.

A fungus photograph courtesy of “brettf” from North Vancouver, who asked for help identifying the fungus on the fungus and lichen identification forum (includes more photos), then submitted it for BPotD via the BPotD Submissions forum. Thanks Brett!

Calocera viscosa has a host of common names: yellow staghorn fungus, staghorn jelly fungus, jelly antler fungus, yellow antler fungus – personally, I'd avoid using a common name with yellow in it, since the colour ranges from yellow to orange.

The epithet viscosa equates with sticky or greasy (viscid), and in this case applies to the greasy surface of the fungus. Like many fungi, it is a saprotroph, obtaining its nutrients from decaying organic matter (in the case of Calocera viscosa, the decaying stumps of conifers).

Photography resource link: British Columbia lost a great nature photographer when David Blevins returned home to North Carolina after completing his doctorate in forest ecology at UBC. There are plenty of images of the flora and fauna of both British Columbia and the Carolinas on his site, and a few from elsewhere. Two of my favourites are Bald-cypress and Water Tupelo Forest and Sabal Palmetto Leaf. If you are a photographer, don't miss his page on techniques.

Adding to the recent trend of south of the Equator images, this photograph from Tasmania is courtesy of Ray in the town of Launceston (sparramc@Flickr | BPotD Flickr Group Pool | original image). Thanks for sharing again, Sparra!

Another day, another plant with a name that's flip-flopped back-and-forth for nearly half a century. Chocolate lily (to Australians – that name means something else to North Americans) has been known as both Dichopogon strictus and Arthropodium strictum over the years. Though many still use Arthropodium strictum, I've opted to use the name suggested by the Census of Australian Vascular Plants. Still, that's tentative – if I could find the resource alluded to by the Pacific Bulb Society (don't forget to check out the image of its roots, quite unique), I might be convinced otherwise.

This species is native to southeastern Australia and northern Tasmania. Unlike the North American chocolate lily, which is described as having an “odour not unpleasant” in the Flora of North America, the Australians sagely call this chocolate lily because it smells like chocolate. I do admit some curiousity in that the scent is sometimes also described as being that of vanilla; I've made a similar association of “smells like chocolate or vanilla” with the South American shrub Azara microphylla (to be featured on BPotD sometime before mid-March). I don't know enough about scents to discern whether the two smells are chemically related in some manner. However, while researching it, I did find this interesting article: Vanilla patch cures sweet tooth: “Scientists have come up with a way to beat chocolate addiction – a vanilla-scented patch.”. It seems like there is some sort of relation, at the least. If you happen to know that the chemistry of these two scents is somehow similar, please add a comment.

For Vancouver area folks: you might like to consider attending this Thursday's meeting of the Native Plant Society of BC South Coast Group. Ron Long is presenting a set of his photographs of British Columbian plants from locations around the province. Who's Ron Long? In his words: “For thirty-six years I have been employed as a full time photographer at Simon Fraser University. For fifteen of those years I photographed exclusively for the Biological Sciences Department so I have a considerable amount of biology in my background and an abiding interest in nature photography.” The meeting is at 7:15pm at the Vancouver Museum, and non-members are welcome to attend! If you'd like more information, please see the link to the NPSBC page.

Botany resource link: Trillium and the Trillium Family – if only information on all genera would be so handily gathered and organized!

(A bit of a treat today! Quentin Cronk, Director of the UBC Botanical Garden and Centre for Plant Research has photographed and written today's BPotD weblog entry. – Daniel)

Tristerix longebracteatus photographed on the Cotopaxi Volcano of Ecuador, c. 3800m. Tristerix is a genus of 11 species of South American Loranthaceae (tropical mistletoe family), with striking hummingbird-pollinated flowers. This species parasitizes shrubs in the paramo of the high Andes. Paramo is a vegetation type above the treeline that consists of cold resistant shrubs and tussock grasses.

Photography resource link (by Daniel): Photomacrography.net is dedicated to macro photography, and includes user forums and some articles. It skews toward insect photography, but the techniques remain the same as for plants.

I'll be taking some plant photographs for this time of year in the upcoming week. In the meantime, though, here is another image from a field trip last June to Lac Du Bois Grasslands Provincial Park near Kamloops, British Columbia. I'm fairly certain this image was taken outside of the park border. I'm also fairly certain that everyone takes a photograph of this dead tree as they walk in.

The grasslands of southern interior British Columbia form the largest portion of the 1% or so of the province that is grassland (most of the remainder are small patches near the Peace River area and the Garry oak meadows of Vancouver Island and the Gulf Islands). Despite containing a disproportionate amount of endangered and threatened species for the province, no provincially endemic vascular plants are found in this region (i.e., plants which are found only in British Columbia and nowhere else in the world). However, there is at least one species that can only be found in British Columbia and neighbouring Washington, Talinum sediforme (Okanagan / Okanogan fameflower depending on which side of the border you reside). There may be more, but I don't know an easy way to gather that information.

I should also explain the three images. The first is digitally processed in the typical steps I take. The black and white used Photoshop's Calculations command with red-red channels blended with soft light at 100%. The last image, however, uses a technique I haven't displayed before on BPotD. If you have ever shot landscapes with film, you'll likely know of Velvia film with its rich, saturated colours – in fact, this is a big part of the stunning colours displayed in the work of many of the photographer's I link to in the resource links. Paul Bleicher has created a Photoshop action that replicates Velvia film digitally so you can process your images as if they were shot with Velvia film; this is what I used for the third image. It certainly makes the original image I processed pale and flat in comparison...

Horticulture / botany resource link: Horticultural Myths from Dr. Linda Chalker-Scott of the Puyallup Research and Extension Center, WSU. Plenty of good information here – thanks to Ron B of the forums and weblog comments for bringing the site to my attention. It should have been linked here a long time ago.

Like all crocosmias, swan crocosmia is native to southern Africa. I suggest reading the excellent account on Crocosmia masoniorum by the South African National Biodiversity Institute for more information.

On behalf of the researchers and staff at UBC Botanical Garden, best wishes to you for 2006!

Photography resource link: For inspiration, photographs of Virginia and West Virginia by Ian J. Plant.