As I've mentioned previously, I was recently at the South China Botanical Garden in Guangzhou, Guangdong Province, for an international symposium on the Magnoliaceae. Following the symposium's conclusion, I went on a tour of southern Yunnan Province in order to see magnolias in the wild. Together with my colleague Andrew Hill, Curator-Horticulturist of the David C. Lam Asian Garden, and about 20 other scientists and magnolia enthusiasts, we saw a huge range of magnolia species in the wild and in botanical gardens. This photograph, however, is of a plant in the Asian Garden here at UBC.

Magnolia insignis is an evergreen tree growing to 30 metres in the wild. The fragrant flowers are about 12 centimetres across when fully open, and they are composed of 9 to 12 tepals. The species is sporadically distributed throughout southwestern China, Indochina, and the Himalayas between 900 and 2600 metres; it is, moreover, remarkably cold hardy (to at least Zone 7). To be honest, a few of us were wondering how last winter, with its brutal temperatures and snow, would affect the health of our Asian magnolias. Predictably, many of our M. campbellii trees lost all of their flower buds, and some even suffered branch death on their limbs; happily, however, nearly all of our mostly untried Asian evergreen species came through with flying colours. You can read more about our sizable magnolia collection in this account by the late Peter Wharton, former curator of the Asian Garden.

There is considerable debate about names of magnolias and the ranking of the various groups within Magnoliaceae. Like the majority of North American scientists, we are now using the conservative two-genus concept championed by Richard Figlar and Hans Nooteboom, which includes only Magnolia and Liriodendron. There is an elucidation of this system on the Magnolia Society web site, here. In China, a variety of systems have been proposed, and the one adopted in the recently published Magnolias in China follows the system of the revered Chinese magnolia taxonomist Liu Yu Hu, which elevates a number of sub-genera and sections to generic level. In that account, there are 8 separate genera (not including Liriodendron), and the species pictured here is classified under Manglietia Blume.

Amaryllidaceae is a family of over 800 herbaceous, perennial, and bulbous species that are distributed broadly throughout the world. Eucrosia is a genus of 8 species endemic to the dry, rocky, western Andean slopes of Ecuador and Peru. Though the type specimen of E. mirabilis was collected in Peru, it has never been recollected there, and recent research conducted by Brian Mathew and Gwilym Lewis reports the plant to be native to southern Ecuador, where Lorax took today's photo.

According to Lorax, E. mirabilis—which means 'wonderful' Eucrosia—is "often referred to as a "lost" species - botanical descriptions exist as far back as 1817, but the type specimen doesn't describe the flower well". She proceeds to write that upon her encountering mirabilis, the plant's "spectacular flowering spike was about 50 cm tall, with white stamens projecting a good 10-15 cm. further than the green umbels. Flowers appeared before leaves after the dry season. It's an Ecuadoran native, thriving in biomes that get a distinct dry season (which is what stimulates blooming)".

The plant, which here hovers as elegantly as the upper part of a cat's eye, has large, fleshy bulbs that are able to survive longs periods of environmental hostility, though often without visible growth. It excels in warm temperatures and well-drained soil, and flowers in late spring and early summer, subsequently growing petiolate leaves that reach up to 30 cm. in width.

Source:

Mathew, Brian and Gwilym Lewis. "Eucrosia mirabilis." Curtis's Botanical Magazine 2.23 (2006): 157-162. ]]> 2009-07-01T00:03:29Z 2009-07-01T14:00:00Z tag:www.ubcbotanicalgarden.org,2009:/potd//10.2808 2009-07-01T14:00:00Z

]]> Thank you to ngawangchodron for posting Today's Botany Photo of the Day, chosen specifically for Canada Day, on our Flickr pool. Steve Coughlin wrote the entry. (Original Image)

Though often classified in the family to which they give their name, Aceraceae, Maples are more properly considered part of the related Sapindaceae, which consists of 140-150 genera and between 1400 and 2000 species—trees, herbaceous perennials, lianas—that are distributed widely throughout the world. Generally, these species have pinnately compound leaves, small flowers, and dry, fleshy fruits.

Acer is a genus of about 125 species, most of which are deciduous trees, though there are also evergreens and shrubby species. The genus tends to establish dense root systems, and is primarily distinguished by its oppositely arranged, mostly palmate leaf configuration. Maples flower in late winter or early spring, and their vivid fall foliage often draws vast amounts of urban dwellers into the countryside. Beyond their popularity as ornamentals, Maples also serve as parts of collections, as integral parts of local tourism industries, as timber, as raw materials for the production of musical instruments, and, of course, as sources of the sap that is eventually converted to maple sugar and maple syrup.

Acer macrophyllum, the tree featured in today's photo, can grow to a height of 30 metres and to a trunk diameter of 1.5 metres. When mature, its trunk is sheathed in an intricately interlaced bark of dark brown. As its name suggests, A. macrophyllum grows the largest leaves of any Maple. Trees generally establish in moist soil near water and are adapted to growing under a canopy. Bigleaf Maple's hard wood is used in the production of furniture, instruments, veneer, and other commercial products as well.

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Crassulaceae is the fourth largest family of succulent (water-retaining) plants. Structurally, the family is the simplest among succulents, consisting of plants that, in general, vary quite little in quantity of sepals, petals, stamens, and carpels. Interestingly, Crassulaceae is, in spite of this structural simplicity, the most diverse succulent family in terms of habitat and climate tolerance, with the native conditions of different genera and species varying from arid deserts to moist marshes, and endurable climates ranging from searing heat to gelid sub-zero cold.

Kalanchoe, a genus of about 130 species, consists mainly of flowering shrubs and herbaceous perennials, though it boasts some annual and biennial species as well. The genus is native to Madagascar and to tropical regions of Africa and Asia.

Kalanchoe delagoensis is commonly known as 'mothers of thousands' and 'chandelier plant'. The species is native to Madagascar, though it is now naturalized in many tropical countries, where it is cultivated as an ornamental. Historically, K. delagoensis has also fulfilled the more practical role of a versatile medical treatment for infections, rheumatism, inflammation, and hypertension. That said, gardeners should note that this power to heal is matched by a power to harm: as many unfortunate grazing animals have experienced, the plant contains poisons (bufadienolide cardiac glycosides) that, if ingested without treatment, induce cardiac arrest.

The plant—which in today's photo seems either painted in pastel or molded from dusty terracotta—generally grows to a height and spread of 1 metre. It thrives in sandy soil with abundant water, adorning itself in waxy green leaves and dangling cylindrical flowers of pinkish-brown. The plants are viviparous, meaning that small plantlets are produced on the vegetative tissues (in this case, on the margins of the leaves). These plantlets drop to the ground, spawning the prodigious amount of offspring that accounts for the first common name mentioned above.

Primary Source:

Rowley, Gordon. The Illustrated Encyclopedia of Succulents. New York: Crown Publishers, 1978.

Cardiocrinum—another herbaceous, bulbiferous member of Liliaceae—is a small genus conventionally split into three species: Cardiocrinum cathayanum, Cardiocrinum cordatum , and Cardiocrinum giganteum. The genus is distributed broadly throughout the sub-alpine regions of northeastern India and Nepal, through several parts of China and northwestern Myanmar (Burma), and into Bhutan as well. Cardiocrinum species generally grow in forests or on hillside slopes, where they excel in a combination of shade, humid air, and moist soil.

Cardiocrinum giganteum, first collected in the second decade of the 20th century, is native to elevated forests at 1200-3600 metres. The plant's hollow green stem reaches its apex at a height of 3-5 metres and spreads its large, leathery, and heart-shaped leaves out to a diameter of around 100 centimetres. In mid-summer, an ensemble of large trumpets, creamy-white or green and internally streaked with red or purple-red, unfold from the lengthening raceme. The plants die after flowering, leaving behind small offsets that will flower some 3 or 4 years later.

Today, the flowers hang quite close together, like members of a swaying choir pushed shoulder-to-shoulder. The fact that they have just arrived combines with our knowledge of their transience to make us ever more attentive to the sweet subtleties of their aromatic melody.

Calochortus, a genus of over 70 herbaceous species, derives its name from the Greek for "beautiful grass". The genus is a member of the lily family, and is renowned for its showy flowers, which rest elegantly atop single stems that rise from perennial bulbs. Calochortus species all have a single basal leaf, inflorescence-supporting bracts, and a perianth composed of three sepals and three petals. These petals and sepals vary from each other in terms of size and colour, and, in this, Calochortus is unique among members of Liliaceae. Though its occurrence seems to be centered in California, where 40 species grow in the wild, Calochortus is in fact quite widely distributed along the western coast of North America, extending from the southern parts of British Columbia through to the northern tip of Guatemala and as far east as the Dakotas. One species, Calochortus nuttallii, is the state flower of Utah.

Calochortus superbus —the species featured in the striking chiaroscuro of today's photo—was first collected in California's Yosemite Valley in the early years of the 20th century. This non-invasive species—commonly called the superb mariposa lily—is endemic to California, where it grows in open meadows, valley grasslands, and foothill woodlands. Generally reaching a height of 40-60 centimetres, C. superbus flowers in late spring and early summer, and enjoys full sun and well-drained soil. Though the plant goes dormant in the summer, it is hardy to zones 7 through 11 and can survive at fairly high altitudes as well (up to 2400 metres). The stems generally bear 1 to 3 upright flowers that take the shape of a small cup; each of the overlapping petals is blotched at the base with a chevron of deep purple or brown surrounded by vivid yellow, though the species exhibits a broad diversity of colour. The exterior of the petals is generally the same colour as the interior, and, as if to pique the curiosity of passersby, it displays a faint, alluring shadow of the intricate internal design.

Source:

Gerriten, Mary and Ron Parsons. Calochortus: Mariposa Lilies and their Relatives. Portland: Timber Press, 2007.

Ribes is a genus of about 150 deciduous flowering shrubby species—the currants and gooseberries—which are primarily native to temperate areas in the Northern Hemisphere, with a few species occurring in South America. Gooseberries are differentiated from currants on account of their spiny stems and often larger fruit. Though they have acquired a measure of notoriety as hosts for the dreaded white pine blister rust (their cultivation actually remains prohibited in some U.S. states), Ribes species—red and black currants in particular—nevertheless have a rich and diverse history as raw materials for human pleasure and practice: the plants have been grown as ornamentals, and they have been used as astringents, as treatments for rheumatism and fever, and as antidotes for digestive, kidney, and hormonal problems as well. Interestingly, the common designator, "currant," is actually a misnomer, and is thought to have derived from a historical mutation of the Anglo-Norman French "raisins de Corauntz" (grapes of Corinth): the dried fruits of Ribes are easily mistaken for the tiny raisins that were famously exported throughout Europe from the Greek city of that name.

Ribes rubrum (red currant) cultivars, which can grow to a height of nearly 2 metres with a spread of almost 3 metres, were first produced in large quantities in France and Belgium in the 17^th century. This rugged species is hardy to zone 6 and enjoys loamy soil combined with either full sun or partial shade. The plants need good air circulation in order to overcome their susceptibility to mildew. The small, pendulous flowers of 'Red Lake', which bloom in late July, are a somewhat unimpressive green-yellow, but they soon enough develop into the sour, fibrous, and vitamin C-rich red berries that are used in preserves, puddings, and pies. Of course, humans are not alone in their appreciation of this sapid little fruit. Birds of all kinds love the berries, and they therefore lay vigorous siege to the plants in order to reap this tart reward. Depending on where Ribes is sited and for what purpose it is grown, this siege can be either to the gardener's delight or to her despair.

The comestible crop was also very important to Pacific Islanders. Cultivation in Hawaii led to the selection of over 150 varieties, including several used for the production of poi—a fermented paste of the cooked corms. Colocasia species contain toxic calcium oxalate crystals, which must be removed by soaking or cooking.

The large, peltate, heart-shaped leaves glow in the setting sun in today's image. Leaves of C. esculenta can grow to 60 cm on plants that reach 1 to 2 m tall. Many variations of colour and form have been developed by a long history of cultivation, lending to the plants frequent ornamental use in modern day gardens. It is a returning perennial in zones 8b and 9, an evergreen perennial in its native tropical climate, and enjoys full sun or partial shade along with copious amounts of water. Here in Vancouver, the plant would not survive the cool winter, but each year it grows from its corms, which are lifted and stored in the fall.

Each day, this showy specimen of over 6 metres presses its flowers back and forth against the glass of my office's window. The tree, one of 130 species subsumed by the Styrax genus, rises high above a small, shallow lagoon, and heaves its thin woody branches over the railing of the wooden walkway that gives entrance to the garden. Looking up from my desk, I see several visitors observing the mass of bees that hovers hungrily in and out of the tree's pendulous white flowers, which hang like small cathedral bells from a scaffold of oblong, leathery green leaves. Nearly twenty years ago, when the seed of this Chinese native (collected at Huangshan, Anhui province) arrived at the garden, it was identified as Styrax dasyanthus, and we affixed a small rectangular plate bearing that name to the same walkway over which, now, with the advantage of two decades, the tree hoists its healthy upper half.

Last month, a re-examination of the tree's inflorescences—undertaken by botanist Beryl Zhuang as part of a garden-wide identification verification project—revealed that this original identification was in fact inaccurate, and that the species was rather—and rather appropriately in this case—Styrax confusus. The re-identification was supported by two distinct findings: firstly, close observation found the structure of the inflorescences to be racemose rather than paniculate (the latter of which is characteristic of dasyanthus); secondly, examination showed the plant's fruit to be considerably larger than that of dasyanthus and less pointed at its apex (more obovoid). Though historically other species of Styrax (S. benzoin, for instance) have offered more raw materials to the sensuous curiosities of man (resins used in perfumes, incense, and medicines), confusus remains a lovely specimen, a fine addition to any garden, and, in this case, a subtle reminder of how the minute mysteries of plants can sometimes mislead even the trained eye of the scientist.

Delonex regia, commonly known as royal poinciana or flamboyant tree, is a fast-growing (up to 1.5 metres per year), threatened native of Madagascar. Its epithets suggest something of the plant's appeal to both the eye and the imagination. In early summer, the tree erupts into a spectacular conflagration of red, and a closer look reveals that each of the tightly clustered flowers has five gently crinkled petals, four of which are nearly uniform in shape, size and rich red hue, while the fifth (the 'standard'), spotted and orange-yellow, rises elegantly to a few centimeters above its peers. Feathery, compound bipinnate leaves underlie the inflorescence. The trunk, which can sometimes reach 50 metres in height, bears smooth, light-brown bark. Due to the strength and complexity of its surface root system, the species is commonly considered invasive, and due to its popularity and abundance in the Caribbean, the tree is often thought to be a native of the region.

Though vulnerable in the wild, flamboyant tree is today naturalized in many tropical areas. It is hardy in zones 9 through 11 and cultivated in several different types of soil. Delonex regia is generally grown as an ornamental, though its seeds are sometimes used practically in percussive instruments like the maraca.

Pictured are two Eremurus × isabellinus hybrids: first, dressed in peach-coloured flowers, 'Cleopatra'; second, an unknown yellow-flowered cultivar, probably 'Image', which only arose this year (in the second year) from amongst the stems of 'Cleopatra'. There are several group names for hybrid foxtail lilies, each referring to a particular place or breeder. For example, the best-known is the Shelford hybrid strain of foxtail lilies, developed by Sir Michael Foster (1836-1907) of Great Shelford, Cambridge, England. Foster was an eminent professor of physiology at Cambridge University, and he served as Secretary of the Royal Society as well. He was perhaps best known as an iris collector, and is remembered for his suggestion that, "horticulture is a pious occupation," substantiating his claim with the assertion that, "the gods rejoice when they see a good man struggling with adversity". Foster was among the first to receive the Victoria Medal of Honour from the RHS. In the popular literature, Eremurus × isabellinus hybrids are known as Shelford Hybrids—often even listed as E. × shelfordii—but 'Cleopatra' is actually a Highdown Hybrid, and 'Image' belongs to an increasingly popular group called the Ruiter Hybrids. Unfortunately, I couldn't find any substantial historical information on either of these two hybrid groups.

Foxtail lilies are challenging subjects, especially in Vancouver's wet winter climate. Their octopus-like, sprawling, fleshy rhizomes require perfect drainage, and the plants need maximum sun exposure to flower well; nevertheless, the hybrids are somewhat easier both to establish and to maintain than the wild species. I once heard the renowned gardener (and garden writer) Christopher Lloyd describe his method for cultivating foxtail lilies. He would dig a large hole in a well-drained, sunny spot, and pour builder's sand into the hole so that it would form a cone (the top of which was approximately 10 to 15 cm below the ground level); he would then lay the rhizome over the cone and backfill with the native garden soil. This would position the crown and arms of the rhizome appropriately and ensure that the rot-vulnerable underside of the rhizome would stay dry. Today's photograph was taken in the plaza at the entrance to the Botanical Garden. The soil here is relatively sandy, infertile and well-drained. The spring-flowering Koelreuteria paniculata (golden rain tree)—which prefers similar dry, sunny conditions—provides the background.

As a person fascinated with plants of all kinds—though admittedly, I'm more familiar with temperate plants—I couldn't help but be impressed with the range of tropical and subtropical plants at the South China Botanical Garden, where I attended the Second International Magnolia Symposium this past May. I should confess, too, that woody plants, especially trees, are my great passion. Leaving magnolias aside, one of the most beautiful groups I saw in the garden was the Elaeocarpus collection. The tree pictured is about 5 m tall and about as wide. Each and every branch was festooned with sweetly scented cream and white flowers. The overall effect of the fringed blooms against the glossy, deep green leaves was exceptionally beautiful. In all, I saw some five distinct species, though there were probably many more in the collection.

The name hainanensis indicates that this species is found on Hainan Island, off the south coast of China (it also occurs on the adjacent mainland and in Indochina). Although unlabeled, the species resembled other trees of E. hainanensis, so this is the name I've provisionally given to it; as there are about 350 species in the genus, however, I'm just as likely to be wrong about the identification. I strongly suspect that many species are grown as ornamentals because of their clean, evergreen foliage and their great beauty when in flower.

In its native tropical, sub-tropical, and warm temperate habitats of coastal Asia (China, Taiwan, and southern Japan), Livistona chinensis—the Chinese fan palm—often reaches upwards of 15 metres (45 feet). At the trunk's apex, the characteristically costapalmate (and scroll down here ) green leaves (which can grow to a diameter of 5 metres) collapse back toward the earth like layers of fountain water cascading softly downward from the peak of their trajectory. For this reason, many happily refer to the species as the fountain palm, and just as the figure of its namesake evokes a sense of sweet respite and replenishment, the species itself produces raw materials for human nourishment and raiment, and it forms a cool canopy through which only cracks of sunlight can penetrate. While it does indeed provide humans and animals with a measure of protection from the heat of the tropical sun, L. chinensis guards itself against the baleful consequences of drought by way of a long tap root that generally extends to the cool, moist depths of 2 metres. Of course, today the palm is a popular domestic and commercial plant that rarely confronts the adverse soil and climate conditions against which it is so hardy: in the warmer parts of North America, it is generally sited in shopping mall pots and alongside manicured highways or caring homes.

Botanical gardens contain multitudes in several senses: beyond the heterogeneity of visible and invisible life forms that inhabit or make use of this land, that is, the garden is by nature home to a broad spectrum of mood and ambience. Odd moments find one immersed in a tour group or a research party, while others are steeped in the tranquility and solitude of an isolated corner or an often overlooked path. Though it was taken in the South China Botanical Garden, which, as a rule, hums with the frantic energy of practical human endeavor and association, this photo seems to suggest the latter form of experience—of leaving the heat, light, and din of the highway and the beaten path behind for the serene terrain of whispers, shadows, and the unexpected.

Rodgersia, a genus of five herbaceous perennial species from the moist valleys and forests of East Asia (Himalayas, China, Korea, and Japan), is known for its large, pinnately or palmately compound leaves, its spreading underground stems, and its sizable paniculate inflorescences (up to 2 m long), which are studded with numerous white or pink star-shaped flowers. The genus is named for the distinguished mid-19th Century United States Admiral John Rodgers, whose exploring and surveying expedition contributed significantly to early American knowledge of the eastern and northern waters of the Pacific Ocean and included the first scientific collection of a Rodgersia species.

The smallest and reportedly least hardy of the rodgersias, R. sambucifolia was first collected by British plant hunter Ernest Henry Wilson on his 1904 expedition to China. The species is native to the provinces of Guizhou, Sichuan, and Yunnan, but is not as well known as most other species. The specific epithet recalls Sambucus, the elderberry, which R. sambucifolia's elegant, deep green leaves resemble quite closely. The species, like all rodgersias, thrives in semi-shade and moist soil, looking well when sited near water. In June, R. sambucifolia's creamy blooms glow; do not wait to take in this refulgent drama, however, for the initial whites and pinks of June soon turn to weaker browns and greens. Fortunately, the handsome foliage more than makes up for any late floral indiscretion, and the plants continue to look fine through the summer with shade and moisture. In winter, the plants die back to the ground cleanly and completely. In the Vancouver area, the species is completely hardy (Zone 7), and a skiff of leaf-mould in the fall is all that the gardener needs in order to maintain a colony; the leaves both feed the plants and protect the ground from the pounding of the coming winter rain.

Euphorbiaceae (the spurge family), which consists of around 300 genera and 7500 species, is native to both the temperate and tropical climate zones. Euphorbia griffithii is a metre-high herbaceous perennial that hails from the eastern Himalayas to the mountains of Myanmar (Burma) and western China. It ignites into bloom in early summer. The cultivar 'Fireglow', which is more deeply coloured than the species, welcomes visitors at the entrance to UBC Botanical Garden with a series of chromatic juxtapositions simultaneously subtle and strong: on its floral bracts, rich reds mix with searing yellows and oranges as if on the palette of an Old Master, while the dark burgundy of the stem and the green of the waxy leaves lend further contrast and contribute to the intensity of the blazing blooms above. This intensity culminates in the fall, when the floral apparatus turns brick red.

The vividness of the bloom, which to some suggests a measure of resilience and assertion, is indeed matched by the vigour with which 'Fireglow' confronts its surroundings. The species is robust enough to withstand both hostile pollutants and the vast spectrum of weather conditions associated with Zones 4 through 9; E. griffithii tends toward the invasive, however, at least in garden situations. Paraphrasing renowned gardener and garden writer Christopher Lloyd, the species is aggressive, and its sustained struggles when matched with a similarly dominant species leave the gardener only to referee. In addition to these somewhat bellicose tendencies, 'Fireglow' has another menacing trick up its sleeve. While the plant's capacity to repel the onslaughts of deer and other animals is undoubtedly a benefit in the garden, gardeners beware, for the milky sap that fills the stems of this beautiful spurge is toxic.

For those wishing to explore the plants of the Himalayas, Laboritoire d'Ecologie Alpine has a searchable database, Flora Himalayan Database, which provides links to other Himalayan flora resources (Original French).