Today's photographs are courtesy of two contributors. Eric Hunt, aka Eric in SF@Flickr shared the first image, and he has a number of additional images here: Saccharum officinarum). 3Point141@Flickr contributed the second image. Thanks to both of you for helping with the Botany and Spirits series!

Saccharum officinarum is a cultigen, a taxon of cultivated origin. Other examples of cultigens previously featured on BPotD include rice and cassava. One of the commercial sugar canes, Saccharum officinarum was hybridized over millenia, with origins in (likely) New Guinea. Many cultivars exist and continue to be bred, in order to improve properties such as disease resistance and sugar production.

Additional reading on the history and use of sugar cane (or noble cane) is available via the Ethnobotanical Leaflets of Southern Illinois University: "Sugar Cane: Past and Present" or James A. Duke's Handbook of Energy Crops: Saccharum officinarum.

In addition to being the largest source for sugar production, sugar cane is used in the production of the distilled alcoholic beverages rum and cachaça. Unlike yesterday's Juniperus communis, where the contribution to gin was flavouring, rum and cachaça are derived from fermented and distilled sugar cane liquids. Cachaça, the most popular spirit in Brazil (1.5 billion litres annual consumption), is made from fresh sugarcane juice that is fermented and distilled. Rum is a bit more complex, in that it can either be derived in a similar manner to cachaça or, more typically, produced from molasses (a byproduct of sugar production from the canes).

Given that sugar cane has been cultivated for millenia, it is likely no surprise that fermented drinks from sugar cane also date back to antiquity. However, distillation of the fermented liquids to produce the true rums only occurred in the 17th century, on sugarcane plantations in the Caribbean. Wikipedia again has an excellent entry (it seems like Wikipedia writers like alcohol) on rum, including suggestions on the origin of the name as well as a history of rum (did you know that Rhode Island rum was considered an accepted currency in Europe for a short period of time?).

Today's image is courtesy of Priscilla Burcher (aka PriscillaBurcher@Flickr), and I believe this is the first time we've featured one of Priscilla's photographs on BPotD, so, thanks and welcome! The image was submitted via the Botany Photo of the Day Flickr Pool (original image).

As noted in Wikipedia, Agave attenuata is one of the few unarmed Agave species. While technically correct, it may be better to use the term "spineless" instead of unarmed, as the former provides additional information; most Agave have spines on the leaf margins (unarmed means lacking spines, prickles, or thorns).

Native to three Mexican states, Jalisco, México and Michoacán, Agave attenuata is associated with rocky outcrops in pine forests at elevations from 1900m to 2500m (6200 to 8200ft.). It is thought to be relatively rare in the wild. In cultivation, however, it is a popular ornamental in warmer climates, and I've seen it in several California public gardens. Many additional images of the species are available via the Plants of Hawaii web site: Agave attenuata, including one that makes me think unpleasant thoughts about others.

A few English common names are used for the species, including swan's neck agave, lion's tail agave and foxtail agave.

Another thank you to Pete (aka UnclePedro@Flickr) for sharing an image with us. Today's photograph of Thelymitra crinita was submitted via the Botany Photo of the Day Flickr Pool. Much appreciated!

Native to southwestern corner of Australia, in one of the world's biodiversity hotspots, Thelymitra crinita is one of about 100 members of the genus. In its native range, blue lady orchid (or queen orchid) flowers from September to November.

Begonia molleri is endemic to the 854 km² (330 sq mi) São Tomé Island, part of Africa's second least-populous nation (São Tomé and Príncipe). It is one of four species of Begonia endemic to São Tomé Island. An additional species is native to both islands, while three other species which occur on São Tomé Island can also be found on mainland Africa.

Evidence points to this species being a paleoendemic--it is believed to have once had a much broader range, prior to the Pleistocene (see: Plana, V. et al. 2004. Pleistocene and pre-Pleistocene Begonia speciation in Africa.. Mol Phylogenet Evol. 31(2):449-61).

Just the photograph today -- exams for Katherine combined with a number of deadlines and meetings for me equals few entries, unfortunately.

Native to southern Africa, Gaziana krebsiana is an iconic perennial of Namaqualand, where it is an important constituent of the region's exemplary wildflower displays. Commonly named in English as terracotta gazania, it is also known as botterblom (butter flower) in Afrikaans. It "owes [this latter] name to the fact that the ray florets are supposed to taste like butter when chewed", according to the comprehensive species account by the South African National Biodiversity Institute's Plantzafrica: Gazania krebsiana.

After a species-level taxonomic revision by Roessler in 1959, 16 species and ten subspecies were recognized in Gazania. However, a 2009 study, "Globally grown, but poorly known: species limits and biogeography of Gazania Gaertn. (Asteraceae) inferred from chloroplast and nuclear DNA sequence data" by Howis et al. (Taxon 58(3): 871-882) concluded with an assertion that reduced the number of taxa to seven well-defined species and one species complex. This complex is termed the K-R clade, and it includes Gaziana krebsiana (the R being Gazania ringens). A couple hypotheses are put forward regarding the species complex: "The K-R clade may thus comprise incipient or very young species, or perhaps these taxa might be considered merely as locally adapted and occasionally interbreeding ecotypes". Whatever the resolution to this question, this species complex is an example of how biological reality resists the "tidy boxes" of names and other concepts; though these are useful, it is always worthwhile to remember they are flawed tools.

Today's entry was written by Katherine.

Thank you James Gaither (J.G. in S.F.@Flickr) for today's photographs of Colutea arborescens (image 2).

Although the leguminous shrub Colutea arborescens is a native to Europe and North Africa, the species is now naturalized in some parts of the United States, Ontario (Canada), and China.

Colutea arborescens grows to be 1-2m in stem height, with bronze coloured bark and yellow flowers. The species blooms in the late spring and early summer, while the fruits develop in the summer. Fruits are brown or purplish, 2 to 3cm long, and dry into papery pods with 3 to 10 olive, brown or black seeds. According to Plants For A Future, the seeds are also poisonous, though the USDA lists the species as not toxic.

The genus name for Colutea arborescens comes from the Greek word kolutea which was used in antiquity for this group of plants, and the Latin word arboresco meaning "woody or tree-like" (literally to become a tree).

Colutea arborescens is commonly known as bladder senna, however they are not the real "senna" which refers to a genus in the same family; Fabaceae (Senna). Even bladder senna is used multiple times as a common name; native to Australia, the purple-flowered Swainsona colutoides, is also known by this moniker.

Colutea arborescens is used for ornamental purposes. The pods are used in dried arrangements, while the trees are cultivated for landscaping. Plants are also used for erosion control and as a revegetator in land reclamation, which is why in California, for instance, naturalized plants may be found in disturbed areas. Colutea arborescens has been known on occasion to become weedy in areas of cultivation.

Spreading phlox is common within its range, though typically reliable resources suggest different ranges. USDA GRIN has a more restricted western range for Phlox diffusa than USDA PLANTS database; the latter suggests Phlox diffusa ranges across much of western North America, going as far east as South Dakota and into New Mexico. This suggests some taxonomic confusion, and this is borne out by some floras recognizing multiple subspecies and varieties within Phlox diffusa, and others using the term "highly variable".

According to some references, today's plants could also be recognized as Phlox diffusa subsp. longistylis, differing from Phlox diffusa subsp. diffusa in having larger corolla lobes (8-10mm long instead of under 8mm in one reference, 5-9mm in another) that are nearly as wide as long (instead of twice as long as wide) and styles 5-6mm long (instead of 2-4mm). However, one reference also notes that some plants do not cleanly fit into either subspecies (i.e., through a mixture of characters such as short styles but large corolla lobes), explaining that this is why some botanists choose to recognize only a single variable species. This would be my inclination in this case.

Flower colour is another variable characteristic. In my experience, pink to lavender is far more common, but Phlox diffusa is one of the easiest species to find white-flowered individuals. While the relative proportion of white to pink individuals is certainly a factor, the task is also made easier by the showiness of these mat-growing plants and the general lack of "colour competition" where they grow. Simply, few other flowering plants inhabit the same niche (mesic to dry rocky slopes and rock outcrops), so the spreading phlox tends to stand out. White-flowered variants is another BPotD series I could do, I suppose, as I suspect I have about 20 species photographed with the typical coloured flower and the white variant. Or, perhaps another half-decade of flower photography will yield a presentation on the topic.

Additional photographs of this species, including the range of flower colour variation, are available from the Burke Museum: Phlox diffusa.

Another couple photographs I had considered for a "plants and mammals" series, these are from mid-July of 2008 in southern Yukon. On the topic of BPotD series, I need a couple more entries for a "distilled spirits" series, so if you have photographs you might be willing to share via email or Flickr, please send me a note to let me know.

Taraxacum officinale (the common dandelion) and Ursus americanus (the American black bear) are commonly associated. About half of my black bear observations in the past decade are instances where the bear was enjoying a dandelion salad; not a coincidence, perhaps, as dandelions are a common roadside weed and most of my observations have been from a vehicle. Others have noted the same: a search via Google for black bears and dandelions. The combination can result in bear jams and habituation.

Like yesterday's Morchella esculenta, the taxonomy of Taraxacum officinale is complicated. In this instance, the difficulty arises with polyploid and apomictic lineages, such that some floras recognize over 70 microspecies. To quote Wikipedia, "As apomictic plants are genetically identical from one generation to the next, each has the characters of a true species, maintaining distinctions from other congeneric apomicts, while having much smaller differences than is normal between species of most genera. They are therefore often called microspecies". More on this phenomenon will be discussed in a future entry, possibly during the next UBC Research Week series, as the University of British Columbia has a number of botanists who investigate apomixis.

Taraxacum officinale is native to Eurasia, but is naturalized widely in temperate parts of the world. The Plants for a Future database references many economic uses for the species, both traditional and modern.

Today's photographs and write-up are courtesy of Ian Gillam, one of UBC Botanical Garden's many exceptional Friends of the Garden. Thank you! Ian writes:

Erodium trifolium is a member of the Geraniaceae native to North Africa. Like many plants of the region it grows in winter, flowers in early spring and is largely dormant in summer drought.

In Vancouver, Erodium trifolium is reasonably hardy outdoors in a well-drained and sheltered area, such as close to the south side of a house. In exceptionally cold winters plants may be damaged or killed.

In common with the related genera Geranium and Pelargonium, successfully pollinated flowers of Erodium produce a lengthening style from the centre of their flowers, growing to about 2.5 cm in this species. As this rostrum develops, the flower heads take on a fanciful resemblance to the heads of long-beaked birds. Botanical names of Geranium, Pelargonium and Erodium derive from Greek names of crane, stork and heron, respectively. Their common names also refer to these birds' long bills. As the seeds mature, the fruiting body turns brown and dries. The ovary splits into five segments, termed mericarps, each containing a single seed. Each mericarp is attached to a tail, an awn, that curls up to pull away from the rostrum.

As Erodium trifolium awns dry, the lower parts coil into tight helices of about five turns, leaving a terminal section curved but uncoiled. A single mericarp is shown above.

The pointed tip has a slight hook and many short, backward-pointing bristles. These features may help mericarps attach and penetrate into fur or feathers, possibly aiding distribution of seeds. Mericarps fall to the ground with the heavier end first. With luck the tip may lodge in some slight crack in the soil. The awn is sensitive to moisture and a slight wetting, even by dew, causes it to unwind within minutes. If the protruding tail catches on a piece of gravel or a plant's stem the power of the unwinding is transferred to the mericarp, thrusting it forward and screwing it into the ground (with a left-hand thread). Should the attempt fail, the sun's warmth will soon cause the awn to coil again and wind may move the whole to a better location for another try at planting.

Tonestus lyallii, also known as Lyall's goldenweed or Lyall's serpentweed, is native to western North America, particularly the central Rocky Mountains and interior mountain ranges of British Columbia, Washington and Oregon. The species is also found in the high elevation Ruby Mountains near Elko, Nevada, and the Coast Range in Siskiyou and Trinity counties of California (where these populations are over 700km distant from the rest of the range).

The Lyall of the specific epithet refers to the Scottish botanist, David Lyall. The genus name is an anagram of the name of a related genus in the Asteraceae, Stenotus. Also a North American genus, Stenotus was split, with several species moving into the newly-named Tonestus by Aven Nelson in a 1904 publication. From the names I've encountered, anagrams are infrequently used; it's been my understanding when this device is used to create a name, it is for a species or group of species that closely resembles its previous one. Here's a search for Stenotus on CalPhotos for comparison. Superficially, representatives from each genus will closely resemble one another, and it's not until either extremely close observation (like Nelson) or diving into a taxonomic key that one may be guided to the characteristics that separate the groups.

Tonestus lyallii is a species of alpine and subalpine habitats, with a preference for gravelly soils or scree.

Katherine is the author of today's entry. She writes:

A big thank you to davallia@UBC Botanical Garden Forums for sharing this picture of Strophanthus speciosus via the UBC Botanical Garden Botany Photo of the Day Submissions Forum.

Strophanthus speciosus is native to South Africa, Swaziland and Zimbabwe. Common names for this species include forest poison rope and corkscrew flower.

Though uncommon in its native range, Strophanthus speciosus is not presently under threat according to Plant Resources of Tropical Africa: Medicinal Plants (PROTA). Strophanthus speciosus is a shrub growing to 4m, or a liana sometimes reaching approximately 16m. This species flowers near the end of the dry season and beginning of the rainy season (September - October) in the wild, while "mature fruits occur throughout the year with a peak in the dry season", according to the above resource. Although the efficacy is unconfirmed by research, it is traditionally used to treat snakebites (in humans and cattle). Alluding to its common name, related species such as Strophanthus gerrardii and Strophanthus luteolus (and possibly this species, as well) are used to generate a poison for spears and arrows (as well as more nefarious purposes).

Strophanthus is derived from the Greek stroph- meaning "a cord or twisted band; turn, twist" and -anthos, or "flower". The genus is comprised of approximately 38 known species, of which 30 occur in continental Africa, 1 in Madagascar, and 7 in Asia.

Unfortunately, this scene from Nitobe Memorial Garden was photographed two weeks ago, so anyone wanting to see the Garden with these colours will now have to wait another year. The red-leaved maple in the foreground is most likely Acer palmatum 'Osakazuki', and I believe it is slated to be moved this winter to another area of the Garden.

Nitobe Memorial Garden was originally planted over fifty years ago, and has been described as one of the most authentic Japanese gardens outside of Japan. Over the next few years, some difficult decisions will be made to renew some of the plantings (e.g., decades-old cherry trees that are declining in health). The challenges will be to do so while honouring the spirit & intent of the original garden design, ensuring the present-day garden is not visually harmed, and, planting (and planning) for the future.

Today's entry was written by Katherine:

Thank you Pete (aka UnclePedro@Flickr) for today's photograph of a Banksia grandis sapling, showing the bright red colour characteristic of young growth.

Banksia grandis is native to Western Australia and can grow either as a shrub (along the south coast, among granite rocks) or more commonly as a tree 5 to 10m in height (sometimes up to 15m). A map of the distribution of Banksia grandis is available via the Western Australian Herbarium's FloraBase website. According to the WA Herbarium, Banksia grandis grows in sandy and laterite soils (soils rich in iron and aluminum, formed in hot & wet tropical areas). Banksia grandis blooms in the summer months, September to December or January, with yellow-green flowers maturing to become bright yellow. The flower heads measure approximately 40cm long and 10cm wide. After flowering, the structure supporting the fruit becomes quite woody, and these cones are used in wood-turning.

Wikipedia notes that Banksia grandis is commonly known as bull banksia, giant banksia or mangite in English. The species is also known as mangyt, pulgarla or Bool gal la by the indigenous peoples, who steeped the flowers in water or sucked them to obtain nectar. The Wikipedia article also mentions that while the differences in growth (shrub vs. tree) are retained when the coastal plants are grown elsewhere, no subspecific taxa are recognized.

Research has been conducted on the reproductive ecology of Banksia grandis by Abbott (see: Abbott, I. 1985. Reproductive ecology of Banksia grandis (Proteaceae). New Phytol. 99(129-148)). One practical application of this research included helping to determine the feasibility of reducing the size of the healthy Banksia grandis populations in order to manage the spread of an associated introduced fungal pathogen, Phytophthora cinnamomi--a pathogen endangering more sensitive and/or threatened species. The Centre for Phytophthora Science and Management shows the extent of Phytophthora cinnamomi in Western Australia, as well as illustrating the impact of the pathogen on native plant communities.

Today's entry was written in the summertime by Alexis, but since I thought it more timely for the autumn, it's been saved until now. Alexis writes:

Courtnay Janiak (Seaweed Lady@Flickr) provides today's photo via the Botany Photo of the Day Flickr Pool. Thank you, Courtnay!

Celastrus orbiculatus, also known as oriental bittersweet or Asian bittersweet, is native to eastern Asia but was brought to North America for ornamental purposes in the 1860s. Today, it has become a problematic invasive species in eastern North American agricultural land, forests, grasslands, and coastlands. Though the species is partial to gap and edge habitats, it is able to establish in shaded forests and remain until the canopy opens. Once exposed to moderate sunshine, it can quickly grow and spread. Growing as a woody vine or trailing shrub, Asian bittersweet will smother other vegetation, obstructing photosynthesis or directly damaging the plants.

This species looks similar to and is often confused with North America's native bittersweet, Celastrus scandens. The two species can hybridize--a trait that, along with competition, threatens the survival of the native species.