Another thank you is in order to J.G. in S.F.@Flickr for sending along these photographs from the San Francisco Botanical Garden (via the UBC BG Botany Photo of the Day Flickr Pool | original 1 | original 2).

Petrophile, as you might guess, translates into "rock-loving". This is indeed the case for this relatively short shrubby plants, as they are found in coastal sandy areas, rocky outcrops and inland gravelly areas (though never too far from the coast, perhaps 150km). Common name for plants in the genus used by people in eastern Australia include conesticks, coneflower and conebush. However, in western Australia (the centre of diversity for the genus), these common names aren't used and it seems they are simply referred to as petrophile.

Petrophile biloba, or granite petrophile, is native to a small area of southwestern Western Australia, near Perth. As noted by FloraBase, this species of hillsides and granite outcrops grows to 2m high. The Australian Native Plant Society provides cultivation and propagation information on it: Petrophile biloba.

Thank you to Douglas Justice for today's write-up.

Another wonderful photograph by Alan Tracey from his recent peregrinations in the southern Andes. Nassauvia Comm. ex Juss. is a southern south American endemic genus of about 50 shrubs and herbs, allied to the genus Mutisia (the climbing daisies). Local peoples refer to plants of the genus as repollito, meaning little cabbage sprout. The individual species of Nassauvia are differentiated in part by, and notable for, the degree of reduction displayed by flowers, inflorescences, leaves and stems. In the genus, the higher the elevation and more extreme the conditions, the more reduced (compact) are the plants. This is a general rule in alpines; however, as you can see from the image here, these are not typical looking "compact" alpine plants. The vocabulary describing this reduction series is somewhat arcane, but for the adventurous, this link opens to the abstract of "A typological analysis of the inflorescences of the genus Nassauvia (Asteraceae)" (the full article is unfortunately unavailable to most viewers).

The genus name honours Charles Orthon, Prince de Nassau-Siegen (1745-1809), who accompanied Louis Antoine Bougainville on the first official French circumnavigation of the globe (1766 to 1769). Bougainville had been charged with officially handing over the Falkland Islands to the Spanish. This is probably the connection with the plants we know as Nassauvia, as at least one species is found in the Falklands. The epithet commemorates the Spanish botanist Marianio La Gasca y Segura (1776 to 1839).

Thank you to DarinAz@Flickr for sharing one of his excellent photographs (contributed via the UBC BG Botany Photo of the Day Flickr Pool | original). Appreciated once again! If you love plants, I do recommend visiting Darin's photograph sets on Flickr -- there's much to enjoy.

Silver senna or feathery senna is endemic to much of mainland arid Australia, with the exception of the state of Victoria. It seems to have naturalized in both Arizona and California. Previously thought to be a member of the genus Cassia, its former scientific name and related common names (e.g., silver cassia or feathery cassia) still persist in many online references.

The Germplasm Resources Information Network (GRIN) recognizes seven subspecies and three nothosubspecies, or naturally-occurring hybrid subspecies. I'm somewhat confused as the Wikipedia page for Senna artemisioides mentions both a subspecies artemisioides and a hybrid subspecies artemisioides, whereas GRIN only recognizes the latter. What I'm not confused by, though, is the fact that there seems to be much taxonomic work to be done with Senna artemisioides and all of its subtaxa. It seems to me that this is one of those instances whereby the process of presently-occurring speciation is denying taxonomists the ability to sort everything into little boxes.

If you are interested in growing this plant, the Master Gardeners of the University of Arizona Pima County Cooperative Extension provide this growing guide. FloraBase, the Flora of Western Australia, provides a few more photographs of Senna artemisioides.

Thanks again to Earl Blackstock for submitting photographs of some of the native azaleas of the eastern USA. The first photograph -- Rhododendron austrinum -- was taken by Earl's granddaughter Libby on April 20. The other image, Rhododendron flammeum, was taken in the past few days. A couple years ago, Earl submitted a photograph of a related azalea, Rhododendron periclymenoides.

Both of today's azaleas and the one submitted a couple years ago are deciduous azaleas and hence members of the section Pentanthera (one of eight sections within the genus Rhododendron). Rhododendron austrinum, or the Florida azalea, is native to Alabama, Florida, Georgia and Mississippi. Oconee azalea (Rhododendron flammeum) is found in one fewer state and slightly further northeast: Alabama, Georgia and South Carolina.

The late Hal Bruce, former plant taxonomist at Winterthur Gardens, wrote extensively about deciduous azaleas in this article for the Quarterly Bulletin of the American Rhododendron Society: "Deciduous Azaleas at Winterthur". For more information, and particularly photographs, you'll also want to visit David Royster's Virtual Rhododendron Garden (see: Native & Deciduous Azaleas of the Piedmont). The photographs on Royster's site also show part of the range of flower colour variation within these species. For growing information and more, Earl has suggested Henning's Rhododendron and Azalea Pages.

I apologize for the lack of a photograph yesterday, but I had student projects to evaluate for end-of-term during the day and then attended the successful Collectors' Plant Auction last night.

Today's photograph is shared by a UBC horticulturist Mathew Vis-Dunbar, who also attended the Native Plant Society of BC's field trip to Galiano last weekend. I am hoping that someone took a photo of Mathew while he was photographing this group of flowers from ground-level.

Erythronium oregonum joins what is now a respectable series of fawn-lilies on BPotD: Erythronium grandiflorum, Erythronium revolutum, Erythronium americanum and Erythronium montanum. These five species represent approximately a fifth of the recognized species of Erythronium. As its epithet implies, giant white fawn-lily (or deer's tongue) is a native to the west coast of North America, specifically British Columbia, Washington and Oregon (and, depending on interpretation of the species, California) west of the Cascade Mountains. Its common name of deer's tongue is due to its oft-mottled foliage, photographs of which can be seen on the Erythronium oregonum page via the Burke Museum.

We encountered this species in multiple locations on Galiano. The best location was Bellhouse Provincial Park (and the road leading to it), where the plants could be found en masse in populations of a few hundred. To my eye, plants growing in shadier and moister conditions seemed a bit more robust than those exposed to more sunlight and drier substrates.

The Flora of North America has a technical description of Erythronium oregonum while the Lady Bird Johnson Wildflower Centre has some horticultural information on giant white fawn-lily.

Ruth is responsible for today's entry. Ruth writes:

My mother, Melinde Sanborn, took this stunning shot of a beached monocot species. Thanks mom!

Although we are not certain of its identity, we believe this to be a species of Dendrocalamus. The pachymorph rhizomes combined with large culms are the best clues. Dendrocalamus is a genus of giant clumping bamboo native to Asia and the Indian subcontinent. It's not uncommon to find members of this genus cultivated in Hawaii, Central America or the West Indies, where different species are variously used for buckets, rafts, edible shoots, construction or charcoal. It is also cultivated as an ornamental in mild parts of North America: Quail Botanical Gardens of Encinitas, California has a few species in their collection. As Dendrocalamus are a clumping type of bamboo, they are less of a nightmare (just less) in the garden. Due to their size, they are not recommended for a small to medium spaces unless regular maintenance is possible.

It's been a while since we've had a species from a vascular plant family not previously featured on Botany Photo of the Day, so I'm grateful to Josh aka gravitywave@Flickr for sharing this photograph of a member of the Linaceae, or the flax family (submitted via the UBC BG Botany Photo of the Day Flickr Pool | original). Thank you!

The Linaceae are divided into two broad groups: the Linoideae (such as today's Linum), which are herbs (or rarely shrubs) with a worldwide distribution, and the Hugonioideae, which are tropical woody plants (and often climbers).

The genus Linum is estimated to have roughly two hundred species. These are native to north temperate and subtropical regions, with an abundance of species around the Mediterranean. In North America, native Linum can be found in all states, provinces and territories. Linum lewisii var. lewisii, commonly known as Lewis' flax or prairie flax, is native to much of western and central North America, as well as northern Mexico.

The Flora of the Canadian Arctic Archipelago has a scientific description of Linum lewisii, as well as additional photographs at the bottom of the page. CalPhotos also has an assortment of images: Linum lewisii.

The flax of cultivation for linseed oil and fibres is Linum usitatissimum.

Today's photograph is from Galiano Island. On Saturday, I went on the Native Plant Society of BC's field trip to the island's Bluff Park and Bellhouse Provincial Park in search of wildflowers and other interesting plants. In all, our list of identified plants in bloom neared thirty, including this one, Lithophragma parviflorum.

Smallflower woodland-star is a member of the saxifrage family. Its genus, Lithophragma, is exclusively distributed in western North America. Nine (to 12) species are recognized, with the centre of diversity in California. Only three species are found outside of California and Oregon: Lithophragma glabrum, Lithophragma tenellum, and Lithophragma parviflorum. These three can be found throughout western North America. Calphotos provides photographs of most species within the genus.

The Jepson Manual provides a description of Lithophragma parviflorum, as does Montana Plant Life: Lithophragma parviflorum. I'm partial to the species because it grows in a broad range of habitats (e.g., sagebrush desert, open forests, prairies) and it is like seeing a cheery old friend when visiting somewhere new on my travels in the west.

Today's photograph is shared with us by Wayne Weber@Flickr via the UBCBG Botany Photo of the Day Flickr Group Pool (original). Thank you!

Greater periwinkle is native to the Mediterranean, but has naturalized in places such as British Columbia, milder areas of the United States and Australia. Despite its utility as a shady groundcover, it is not recommended for use in many areas due to invasiveness. The California Invasive Plant Council rates it as "moderate", and this species also finds its way into the Global Invasive Species Database: Vinca major. This latter site provides this brief description of the species: "Vinca major is introduced to new locations usually as an ornamental or medicinal herb. It spreads locally from dumped garden waste, plant fragments carried downstream and as a garden escape along shady corridors. It grows most vigorously in moist shady areas in forests, along streams and urban areas. Once established the herb competes with native vegetation by smothering all native groundcover vegetation and preventing the regeneration of trees and shrubs. Vinca major is a serious threat to the understorey of forested areas and streamside vegetation."

The Plants for a Future database provides a list of traditional medicinal uses. MissouriPlants.com has additional photographs and a description of the plant, as well as a brief argument for the use of scientific names: Vinca major.

Thank you to Douglas Justice for today's write-up. Douglas writes:

Thanks to Alan Tracey for these photographs from his recent trip to Chile.

Adesmia is a genus of about 230 herbaceous and shrubby species native to the montane and alpine regions of South America. They have pinnately compound leaves, legumes covered with shaggy red hairs and classic papilionaceous flowers.

The classic pea flower is composed of a broad, upright "banner" or "standard" petal, two side, "wing" petals and two lower petals partially fused together to form a "keel". The keel encloses the stamens, which normally form a tube for part of their length (they are free in Adesmia) and surround the ovary and lower part of the style. The five petals are inserted inside the cup-shaped base of the calyx. Pollinators (probably bees in this case) are attracted to the nectar that forms in the cup at the base of the petals. To reach the nectar, they must stand on the keel, which deflects and splits open under the insect's weight (but only when the anthers are ripe), tripping the stamens to fly up and deposit pollen on the insect's body. Once the mechanism is tripped, the style, which is bundled with the stamens, is also forced into position to be brushed by foraging insects. However, peas are protandrous (proto = first + andro = male) and the female parts do not become receptive until after pollen is shed. Protandry, which is typical of bee-pollinated flowers, helps prevent self-pollination. Pollination takes place once the stigma (the pollen receptive surface at the tip of the style) is ripe, presuming the visiting insect is arriving already dusted with pollen from another flower.

Adesmia longipes grows to about 10 cm tall in mid- to upper-montane areas of south central Chile (and is also found in Argentina). Plants are herbaceous and winter deciduous. The name Adesmia (a = without + desmos = a bond) refers to the stamens, which are not fused, as is the normal condition in this subfamily (Faboideae) and the specific epithet longipes means "long-stalked" (presumably in reference to the flower stems). The common name, pasto de guanaco, means "fodder of the guanaco". The guanaco is a small llama relative native to the Altiplano of South America.

...and another thank you to Jackie Chambers for sharing both today's photograph and write-up. Jackie writes:

Paxistima myrsinites is currently flowering in UBC Botanical Garden's Native Garden. Although they may not be the showiest of spring flowers, those fascinated by detail will appreciate these very tiny maroon flowers, just 3-4 mm wide. The flowers, each with four petals and four stamens, are held in clusters in the leaf axils along the branches. It is interesting to note that the structure of these flowers is very similar to other members of the family. You can use Flowering Plant Families from the University of Hawaii to compare the flowers of other Celastraceae and observe these similarities.

The thick, leathery leaves of Paxistima myrsinites are oppositely-arranged along the stem. Oval in shape with toothed margins, the leaves can be 1-3cm long. For more photos of this species, see Paxistima myrsinites via VirginiaTech.

False box, or mountain boxwood as it is sometimes called, is an evergreen shrub ranges in height from 20-80cm tall, and can have an erect or prostrate growth habit. Its reddish-brown branches may be either smooth or ridged.

Paxistima myrsinites is native to the coniferous forests and dry mountain slopes of British Columbia. Its native range extends south along the west coast into California and northern Mexico. For more information and a map of its BC distribution see E-Flora BC: Paxistima myrsinites.

Thanks again to buildingadesert@Flickr, aka Claire W., for contributing an image to Botany Photo of the Day (via the BPotD Flickr Pool (original image)).

Cyclopia pubescens is a small shrub native to the Cape Province of South Africa. It belongs to a closely-related group of plants collectively known as the honeybush teas (see profile of Cyclopia genistoides on PlantzAfrica).

There is little information specifically about Cyclopia pubescens on the web, unless one does a little digging and discovers this 2008 thesis by Nicole Du Toit: Molecular phylogenetics of Cyclopia Vent.and its position within Podalyrieae (Fabaceae). Included within this thesis are photographs of Cyclopia species, including Cyclopia pubescens (PDF) and habit and geographical distribution information (PDF). This latter reference reveals that Cyclopia pubescens is "A rare and highly localized species that has only been recorded from the foot of the Vanstadens River Mountain west of Port Elizabeth, growing in marshy areas."

The Tropical Food Plants Conservatory at Montréal Botanical Garden is newly-renovated, and is one of the highlights of a visit to the many MBG glasshouses. Most of the other glasshouses had plant displays with little interpretation. By contrast, the Tropical Food Plants Conservatory had an excellent mix of plants, interpretative signage, and accompanying displays. Well worth the visit!

Pineapple was previously featured on BPotD a few years ago: Ananas comosus (worth revisiting for an interesting link about "pressure and the keratolytic effect of bromelain").

Wild relatives of the pineapple are native to southern Brazil and Paraguay. It was cultivated and spread throughout South and Central America by indigenous peoples prior to European arrival. Within 150 years, it was introduced into cultivation in many tropical and subtropical regions around the world as the fruit was valuable in the prevention of scurvy.

Cal's Plant of the Week featured Ananas comosus in March of 2001, and it includes a photograph of a plant in flower (you may want to compare that flowering bromeliad with Tillandsia lindenii from a few days ago).

Wikipedia has a fairly detailed account on pineapples with a good set of references for additional reading.

Thanks again to ngawangchodron@Flickr aka Lotus J. for sharing another one of her images with us (Botany Photo of the Day Flickr Group Pool | original). Appreciated as always!

It is the rhododendron time of year here in southwestern British Columbia, and it's not just the Finnerty Gardens in Victoria (site of today's photo) that are full of rhododendron blossoms -- UBC Botanical Garden has come alive with them as well (and, if flowering cherries are more your cup of tea, the cherry blossoms at Nitobe Memorial Garden are being celebrated this upcoming weekend).

The little-known cultivar 'Helma's Joy' was registered by Dr. Herman Vaartnou (scroll down) in 1988. Vaartnou was a rhododendron hybridizer and "a key architect of UVic's Finnerty Gardens". It is derived from selfed Rhododendron macabeanum (photo for comparison) and is a member of the Pontica subsection of the genus Rhododendron.

Since the weather turned from sunny and spring-like to cold and windy, I thought I'd share a couple photographs from my trip to Alaska last year. These two images of Aconitum delphiniifolium, or larkspur-leaved monkshood, were taken approximately 300km apart as the crow flies. Aconitum delphiniifolium is so morphologically variable that Eric Hultén recognized three intergrading subspecies (two of which he described and published), but the Flora of North America account for Aconitum delphiniifolium has chosen to "...defer[red] formal recognition of infraspecific taxa within this species pending population studies" in concordance with other taxonomists.

Like all species of monkshood, Aconitum delphiniifolium is deadly poisonous when ingested in small amounts, thanks in part to the presence of delphinine.

Pollinators include bumblebees, as I was hoping to get a photograph of the one emerging from the flower in the first photograph (I have an out-of-focus photograph of the same flower with the bee's wings emerging from the flower). The second photograph was from the first time I (delightedly) encountered this plant in the wild, and careful inspection of the lower-most flower in the photograph will reveal a second pollinator: flies.

On a different note, if you use Twitter, you can now follow updates from UBC Botanical Garden: UBCgarden on Twitter. Katie Teed, the garden's new marketing and events manager, posted the announcement here: Follow UBC Botanical Garden on Twitter.

Douglas and I have tentatively identified this as the cultivar 'Lynwood', though it could be another.

Ruth contributed the write-up for the rest of this entry. Ruth writes:

Thank you to fotrristi@Flickr for sharing today's photograph via the Botany Photo of the Day Flickr Pool (original).

Thanks to their aggressive, sprawling nature, the forsythia you will most often encounter is this hybrid of Forsythia viridissima (an upright, green-stemmed species) and Forsythia suspensa (an arching, weeping species).

Each spring at my old, colonial home in New Hampshire, my father and I would go out almost every week to snip branches off our forsythia bushes to garnish our dining room table with. The fresh floral smell with the sprightly, yellow colour truly brought the long awaited spring season into the home.

These often spindly bushes are ridiculously easy to grow. Our neighbour pulled up one that became too big for his backyard. We dragged a chunk of it home, stuck it in a shallow hole and watered it. It had no problem adjusting to its new home.

A full sun location will get the best results, but forsythia are not picky. With too much shade they can become bare and woody. It is a good idea to cut them back each season to keep them dense, but please refrain from shaping them into balls or lollipops.

Forsythia bushes will grow to be a maximum of 6 feet and sprawl to be almost twice their height if not maintained. The flowers are four-lobed or 4-merous which is convenient for the memory. The four petals of the corolla are adnate at the base, fusing to form a tube. Often the buds can be sensitive to the harsh northern and prairie winters, although the branches will survive through temperatures exceeding -38 ºC. So if you live in an extreme environment, and your Forsythia doesn't flower this year, just hang on and maybe next year it will snap out of it.

Douglas Justice contributed today's write-up. Douglas writes:

Thanks to Alan Tracey for today's image. Alan recently traveled to the Chilean Andes, where he took many photographs of fascinating and unusual plants. We hope to show a number of Alan's excellent images over the next few weeks.

Chusquea (mountain bamboo) is a New World genus of woody, evergreen, semelparous (= monocarpic; i.e., once flowering) bamboos, native from northwestern Mexico and the West Indies, south to southern Chile and Argentina. They are differentiated from most other bamboos by their solid, pith-filled culms, although at least two species are reputed to have hollow culms. Chusqueas also typically have dimorphic branch buds at each node (there is usually one large central bud with smaller subsidiary buds arranged below and to the sides), and lack both fimbriae and auricles. Auricles are tiny outgrowths of the culm leaf sheath and are characteristic of many bamboos, while fimbriae, often called oral setae, are the bristle-like hairs associated with them. Nearly all species are reported to have pachymorphic (i.e., short, thickened and freely branching) rhizomes. Such rhizomes produce clumping, rather than running, bamboos. See Chris Stapleton's Bamboo Identification page for an excellent primer on the subject of bamboo identification.

Chusquea culeou is the hardiest of its genus, but is still relatively rare in cultivation. It suffers badly from cold winters in the Vancouver area, as the exposed portions of the culms burn back when temperatures drop to anything less than minus 10°C for an extended time. This species is known as the foxtail bamboo because, in the most commonly cultivated forms, its multiple, leafy, nodal branches are thickly produced and are all approximately the same size. This creates a tufted, bottle-brush effect along the upper part of the culm. Another significant ornamental characteristic is the contrast between the bright green to dark brown culms and their persistent, papery straw-coloured sheaths, a feature most evident on the taller growing forms. The species is evidently quite variable, and in some places, grows to as much as 7.5 m tall. The mature plant pictured here, and those nearby (according to Alan) grow to only about 2.5 or 3 m tall.

A further notable characteristic of the species is that it is taxonomically confused. Some authors attribute this to the fact that chusqueas in the southern Andes are actively speciating. Add to this the fact that Chusquea culeou evidently flowered in a number of places in the early 1990s and copious amounts of seed were subsequently planted. These factors go a long way to explaining the variability within the species, the proliferation of names, and their sometimes contradictory descriptions. For an excellent profile of the genus, see "Chusquea -- Mountain Bamboo of Latin America" (PDF) via the RHS journal, The Plantsman.

Just the photograph today, folks -- you can read more about California poppy by reading these two previous entries: Eschscholzia californica 1 and Eschscholzia californica 2.

Thank you to San of the UBC Botanical Garden Forums for sharing today's photograph and entertaining write-up with us (original thread posted here). San also authors a weblog, Hort Log -- Horticulture in the Far East; it contains many fascinating posts about both horticulture and nature in Singapore.

San writes:

Death at Calamus Avenue

A gruesome murder along the jungle trail...

Synopsis of crime: The accused is a species of Cordyceps, a parasitic fungus that had infected a Euglossa bee some days/weeks back. Slowly, its mycelial filaments had spread into the internal organs and sucked the bee dry. But the depleted zombie bee must complete one last act before it was allowed to rest in peace. By not ingesting the vital muscles for movement and manipulating the nervous system of its host, the fungus drove the bee to stagger towards the direction of bright light, in this case an elevated stem of a rattan (Calamus sp.), before pulling the final trigger, destroying the brain and locking its host eternally in a characteristic rigor mortis with limbs and wings outstretched. Its fruiting bodies then sprout from the cadaver as shown in the photo, and are unhindered and free to release the spores at a high and exposed location to cause greatest distribution of its progeny.

Verdict: Guilty of murder and body snatching.

Daniel adds: According to Wikipedia, approximately four hundred species of Cordyceps have been described, primarily from eastern Asia. All members of the genus are entomopathogenic, and some have been used as biological control agents.

For additional photographs of Cordyceps and related fungi, you can visit the Cordyceps site. And, for those of you who prefer video, the BBC has posted this clip from The Plant Earth: Cordyceps: attack of the killer fungi (sorry, can't embed this one).

Here's a photograph from my trip to the glasshouses at Montréal Botanical Garden in late January. Tillandsia lindenii, or blue-flowered torch, was planted / placed in numbers throughout the tropical rainforests conservatory. Native to Ecuador and Peru, the epiphytic Tillandsia lindenii can be found growing on tree trunks, tree hollows and even rocks & sandy soils in its native rainforest habitat.

Tillandsia lindenii is considered to have a "paddle-shaped inflorescence" by bromeliad collectors (source: Tillandsias with Paddle-shaped Inflorescences). The paddles are composed of dense, flattened pink bracts from which the large, bluish flowers emerge. A closely related species, Tillandsia cyanea, differs somewhat, including that its flowers are (usually) not white-throated and the paddles are differently-shaped (for more, read the article on Tillandsia cyanea and her Big Sister -- Tillandsia lindenii (PDF)).

The epithet lindenii, I believe (haven't been able to track down a reference), commemorates the Belgian botanist and explorer Jean Jules Linden.