Posts tagged ‘flowers’
Smithsonian Gardens kicked off Pollinator Week this Tuesday, June 21, 2016 by unveiling its newly renamed Pollinator Garden outside the Smithsonian’s National Museum of Natural History and holding its third annual Pollination Party.
When Smithsonian Gardens first opened the 11,000 square-foot Butterfly Habitat Garden in 1995, its goal was to emphasize natural plant/butterfly partnerships and educate visitors about ways they could help these partnerships thrive. Twenty years later, we saw a need to expand the mission of this garden to tell a broader story of the often fragile relationships between plants, pollinators, and people.
This change reflects the growing importance of supporting pollinator health championed by the formation of a task force by President Barack Obama in 2014 and the implementation of the Million Pollinator Garden Challenge. As a participant in this task force, Smithsonian Gardens hopes that the reinterpretation of this garden will educate visitors about the wide diversity of pollinators and the types of plants that support them. The garden’s assorted plantings also show strategies for creating beautiful pollinator-friendly gardens.
The garden’s new theme leads visitors on a ‘Pollination Investigation’ to discover the who, what, when, why, where, and how of pollination by examining the unique relationships between a variety of pollinators—from butterflies and bees to flies and beetles—and flowers. With one in three bites of food we eat dependent on pollinators, it is vitally important that we all work to protect and strengthen pollinator populations.
We hope you can visit the newly renamed garden and join us in protecting the pollinators all around us!
The Smithsonian Gardens Orchid Collection contains an amazing assortment of species and hybrids. I come to work each day with great anticipation of what new marvel has unfurled overnight. I am never disappointed. Our interiorscape staff selects the most stunning plants for our orchid display cases outside the Warner Bros. Theater on the first floor of the National Museum of American History (NMAH). This week’s display features a group of orchids from one of my favorite genera, the fascinating Brassia.
Better known as spider orchids, Brassias are beloved for their long, narrow, ribbony sepals and petals. One of the orchids currently on display is Brassia Rex, a hybrid of Brassia verrucosa X Brassia giroudiana, which is known to have greater vigor and larger flowers than either parent. Created in the 1960s by the venerable orchid breeder Goodale Moir, this exceptional hybrid is a wonderful addition to every collection that has space for it. Beware, however, as it can grow into a monstrously large plant.
It has long been believed that Brassias evolved flowers which—through a strategy known as brood site deception—mimic the appearance of spiders in order to attract female parasitic wasps of the genera Pepsis and Campsomeris that target spiders as hosts on which to lay their eggs. This ‘imitation’ strategy is evident in many types of orchids that use flower smell, color, and texture to appear to be suitable places for pollinators to deposit their progeny. Ecologists in Central America, however, have recently noted that while parasitic wasps do indeed visit Brassias and pollinate them, they do not appear to lay eggs on these orchids. As a result, this finding disproves brood site deception as the reason for Brassias’ spider-like appearance. While the true reason for the spider orchid’s form remains unknown, discussion at a recent orchid conference brought up the possibility that these wasps simply like the look of these flowers.
This raises a fascinating question I’ve been mulling over recently: Is it possible that there is an aesthetic component to orchid evolution? Charles Darwin thought this to be the case and pointed to the sexual selection of mates in various animal species as evidence. Perhaps pollinators also select showy flowers such as Brassias for their ‘attractiveness.’ This question has yet to be answered and is just one of the many reasons I find the mysterious field of orchid ecology so fascinating.
-Tom Mirenda, Smithsonian Gardens Orchid Collection Specialist
Sunday is the final day of the 2016 orchid exhibit, Orchids In Focus, at the United States Botanic Garden (USBG). It has been an interesting season to say the least, with seventy degree weather in January and gusting winds throughout March. Most of our show plants are bloomed out and will start their recovery for next year’s blooming cycle. Our species orchids are not on such a rigid schedule and are still living the slow life in the greenhouses, blooming when they please and offering visual fireworks of color amidst the overwhelming background of green foliage.
Scaphyglottis bidentata is a dazzling miniature orchid from Central and South America. This species exhibits spectacular red-orange flowers, a pollination syndrome for ornithophily, or bird-pollination. Several other Scaphyglottis with large (relatively), bold flowers were previously classified under a distinct genus, Hexisea but were morphologically similar enough to the former Scaphyglottis grouping to be lumped together. One of the major defining morphological characteristics of species in this group is that the pseudobulbs are stacked (see inset photo).
Another striking pop of color found in our species greenhouse comes from Dendrobium bracteosum var. tannii. If you look this one up, you won’t find tannii mentioned anywhere because the name has never been formally published. This variety is a miniature form of the species. To give you an idea of the size difference the flowers on our specimen are no longer than a centimeter in diameter, which is less than half of the typical size.
Dendrobium sanguinolentum is a pendant growing epiphyte found in Thailand, Western Malesia and the Philippines. This species is known as “The Blood Stained Dendrobium” because the flowers typically have splotches or stains of violet at the edges of the sepals and petals. The plant below may be an alba form of this species since there are no stains evident on the pale yellow flower.
This week’s grand finale is Myrmecocattleya Claudia Elena. This fantastic hybrid with such vivid coloration is a cross between Myrmecophila tibicinis and Cattleya dowiana. In the wild, the ranges of these two species do not overlap, but since they are both part of the Cattleya alliance, hybridizers are able to successfully interbreed them. Myrmecophila flowers are typically one to two inches in diameter, but when crossed with a large flowered Cattleya, they almost triple in size!
Photographs are a wonderful way to explore nature’s diversity, but nothing compares to experiencing it in person. If you are in the Washington, D.C. area, make sure to take a final trip to the USBG to see our orchids on display before the exhibit ends on the 17th!
-Julie Rotramel, Living Collections Specialist
It’s finally spring! Today marks the fifth day past the Spring Equinox and it seems like nature is as ready as we are for the change in season. Around the city cherry and magnolia trees are bombarding the city with their pink blossoms and fresh fragrance. Splashes of color from daffodils and pansies are everywhere. Though the season’s change is much more gradual in our orchid greenhouses, this time of year still finds unparalleled variety and interesting stories to tell in our species collection.
This first species was part of a donation we received last summer. It entered our collection as Acianthera aculeata, but now that we have seen the plant in bloom, it doesn’t quite match the type description for the species. A proper identification will require more research for our orchid curators.
Regardless of its specific name, one characteristic I find fascinating about this orchid and many other Pleurothallids is that the flower spikes arise from the base of the leaf rather than closer to the root structures. This makes the flowers appear to grow right on the leaf surface, which has an interesting effect. Many Pleurothallids are thought to engage in brood site deception, and it can be speculated that these small, wine colored flower umbels mimic the perfect egg-laying site for the plant’s pollinators.
Mediocalcar decoratum is a mat forming epiphyte found in the cloud forests of New Guinea. The miniature orange and yellow bell-shaped flowers are scattered evenly throughout the foliage like someone’s lost candy corn and lend a generally cheerful aspect to the plant. This may be why it is commonly known as the Charming Mediocalcar.
Last but not least is the ever popular Dendrobium secundum, commonly referred to as the Toothbrush Orchid. This often pendulous species is found throughout Southeast Asia. Its inflorescence of bright pink flowers opens successively (but not fully) at the end of a leafless cane giving it the appearance of bristles at the end of a toothbrush handle. The alba form is also quite beautiful with waxy white flowers and a yellow lip.
To see more of our collection, visit the orchid exhibit, Orchids In Focus, at the United States Botanic Garden now through April 17th.
-Julie Rotramel, Orchid Collection Specialist
It’s March and it definitely feels like spring. This week’s blooming orchid selections are inspired by the tropical weather we’ve been having the past few days. Our species greenhouse has been looking rather tropical as well…
First on our list this week is Bulbophyllum saurocephalum, which is an epiphytic Philippine species. This odorless plant is also known as the Lizard Head Bulbophyllum because of the numerous tiny flowers that seem to be rearing their striped heads from the surface of the rachis.
Another drastically different Bulbophyllum that is blooming not far from B. saurocephalum is Bulbophyllum compressum. This is a hot growing Indonesian species found at lower elevations, with beautiful, ovate floral bracts of up to 30 delicate,white flowers.
I tend to gravitate towards the strangeness of Bulbophyllums, but I recognize that there are many other genera that are equally fascinating and worthy of mention. Below is the tiny flowered Tolumnia bahamensis.
Not only is this a fascinating North American species, it is highly appropriate to our tropical theme for this week. This species starts its life as a terrestrial in sandy soil, and as it matures, will send out growths that attach to taller plants, transitioning to an epiphytic habit. Tolumnia bahamensis is only found in Atlantic coastal scrub habitats and is considered highly endangered. Atlanta Botanical Garden has been leading reintroduction efforts in Florida with much success.
To see part of the Smithsonian Gardens Orchid Collection on display, visit the Orchids In Focus exhibit at the United States Botanic Garden through April 27!
–Julie Rotramel, Living Collections Specialist, Smithsonian Gardens
The Bletillas are nearly in bloom, and we all know what that means—the annual orchid exhibit is upon us! This week’s post is a special preview of the exhibit, Orchids in Focus, which is produced in partnership between the United States Botanic Garden (USBG) and Smithsonian Gardens and opens this Saturday, February 27 and runs through April 17.
Some of my favorite orchids to photograph are the ones with barely emergent flowers. There is a sense of anticipation in the sight of unfurling petals, like those of the terrestrial Bletilla striata. Developing flowers often display curious shapes that remind us (like so many things) that there is a special beauty in the journey. Brassidiums are some of the best exemplars of this, since their elongated flowers have to unfold from buds that are the size of a fingertip.
Orchids in Focus, which features plants from the Smithsonian Gardens Orchid Collection and the USBG’s collections, is also emerging from its so-called bud. My visit to the conservatory this past Wednesday found a flurry of activity in the East Gallery and finishing touches being put into place in the main Garden Court.
I was able to catch up with a former Smithsonian Gardens intern who is now an orchid grower at the United States Botanic Garden. Justin gave a tour of the work-in-progress and it is clear that it will be quite a spectacle.
The exhibit’s theme highlights orchid photography and is surprisingly interactive since the photography in question is not only images you look at on the walls, but also what YOU take during your visit. Large frames have been constructed in the Garden Court for visitors to pose behind as they are “framed by orchids,” and another station for “orchid selfies” has been designated in front of two exquisite green walls. According to Justin, each side of the green wall takes five hours to build since orchids must be placed individually in the small pockets covering the surface. It sounds like a painstaking process, but the result is magnificent.
The East Gallery houses a tropical forest display which will feature terrestrial orchids from the understory and epiphytic orchids from the canopy on respective sides of the room. Over the next couple of days, USBG staff will be working hard to complete the exhibit, those last few flowers will finish opening, and your job… build anticipation, and get those cameras ready!
–Julie Rotramel, Living Collections Specialist
Winter is one of the most prolific bloom times in the Smithsonian Gardens orchid greenhouses and each year I am astounded by the diversity that is on display. I have a predilection for miniature orchids, for bizarre traits and unique stories and the two orchids featured today will not disappoint.
Bulbophyllum saltatorum var. albociliatum is an exquisite species found widely across Central Africa. Its winter-blooming flowers are no bigger than a thumbnail, and like many Bulbophyllums, the lip has been dramatically modified. In this case, the modification takes the form of a bright pink fringe, which acts as a lure for small flies who end up inadvertently pollinating the flower. This species is also rather unique for a Bulbophyllum because its scent is quite pleasant (at least to my olfaction).
Fringe is not purely used for deceptive purposes. This characteristic, along with colorless flowers and night fragrance is a pollinator syndrome for Hawk Moths. Various species of Brassavola and Habenaria exhibit a unique variation of this morphological adaptation, and offer nectar rewards to their nocturnal visitors. It is not certain what characteristic of this fringed lip appeals to the Hawk Moth, but the convergence of this trait across unrelated orchid genera implies that it is pollinator specific.
In their infinite diversity, orchids always manage to deconstruct the carefully deduced generalizations scientists make about their biology. The Clowesia below, Clowesia Grace Dunn, is a hybrid between Clowesia rosea and Clowesia warzewiczii and as you can see, has an arresting display of fringe on its lip as well.
These flowers are NOT moth pollinated, rather they are visited by crepuscularly active Euglossine bees that collect their fragrances in the form of oils to woo lady bees. Typically, Euglossine bees are generalists, and will collect fragrances from a number of different species. It has been theorized that the fragrances of Clowesia species change throughout the day, with an “optimal fragrance” either before dawn or just after dusk when their pollinators are most active. This may seem like a wild concept, but many biological functions occur in a cyclical fashion, and solely night fragrant orchids are commonly referenced. It makes sense that the same mechanism would be at work in crepuscularly, diurnally and nocturnally fragrant plants.
Daily fragrance fluctuations are not unique to Clowesia, and have been studied previously in Arachnis, Vanda, Spathoglottis and Oncidium (Goh, 1983), among others. The variation in fragrance could be influenced by changes in acidity due to CO2 production during Crassulacean Acid Metabolism (Goh, 1983) and is decidedly affected by photoperiod, an indication that fragrance is regulated by a circadian rhythm (Altenburger & Matile, 1990).
I never considered the importance of physiological constraints playing such a vital role in the evolution of plant-pollinator relationships, but evidence for this “biological clock” of fragrance emission throughout the plant world is incredibly fascinating. Orchid pollination is a beautifully complex fabric of not only interactions (deceptive or otherwise), but the timing of these interactions. As I am often reminded, NOTHING is coincidence, but the intricacies of evolution often seem astoundingly fortuitous.
–Julie Rotramel, Living Collections Specialist
Altenburger, R., & Matile, P.. (1990). Further observations on rhythmic emission of fragrance in flowers. Planta,180(2), 194–197. Retrieved from http://www.jstor.org/stable/23380097
Goh, C. J.. (1983). Rhythms of Acidity and CO2 Production in Orchid Flowers. The New Phytologist, 93(1), 25–32. Retrieved from http://www.jstor.org/stable/2431891