Continuing the series on the Ranunculaceae, or buttercup family, here is another brief entry:
This photograph of Aconitum columbianum was taken in mid-July in northern Washington. Columbian monkshood or western monkshood is primarily western North American, though disjunct populations occur in New York, Wisconsin and Ohio. Like all aconites, it is quite poisonous.
Key to Figures / Image Credits
Figure 1. The photograph of Mentha spicata was shared by Doug (shyzaboy@Flickr) of Troutville, VA via the Botany Photo of the Day Flickr Pool). Thank you for the contribution, Doug!
Figure 2. The illustration of Cinnamomum zeylanicum is from Köhler's Medizinal-Pflanzen (Band I), via Wikimedia Commons.
Figure 3. The photograph of the larva of Trichoplusia ni is courtesy of Alton N. Sparks, Jr., University of Georgia, Bugwood.org, Wikimedia Commons.
A belated ending to the Celebrate Research Week @ UBC series, due to a little bit of miscommunication. Here is the last entry for the series this year, organized by Claire. Claire introduces today's UBC researcher:
Yasmin Akhtar is a research associate in the insect toxicology lab with Dr. Murray B. Isman and lectures in the Faculty of Land and Food Systems. She works with botanical insecticides and antifeedants.
Yasmin writes: Culinary herbs including mint (Mentha spicata) (Figure 1) and spices such as cinnamon (Cinnamomum zeylanicum) (Figure 2) are used as insect control agents. Figure 3 shows a cabbage looper (Trichoplusia ni) larva, considered to be an agricultural pest.
Plants are sources of a bewildering array of natural products including terpenoids, phenolic and alkaloids, likely exceeding 100,000 chemical structures. Many of these chemicals provide defensive functions for the plants protecting them against herbivores and pathogens. Based on their defensive chemistry complex, vascular plants have been considered a valuable resource of natural insecticides, insect growth regulators, and behaviour modifying agents. Behaviour modifying agents may influence the feeding and oviposition (egg-laying) behavior of insects and may also serve as repellents.
The main focus of research in our lab is the development of botanical insecticides and antifeedants. We are exploring the potential use of natural pesticides based on plant essential oils. Some of these oils and their constituent chemicals are widely used as flavoring agents in foods and beverages and are even exempt from pesticide registration in the United States. Plant essential oils meet the criteria of reduced risk pesticides (Isman, 2008).
Plants producing essential oils that have been exploited for insect control include a number of herbs, most notably from the mint family (Lamiaceae), such as garden thyme (Thymus vulgaris), rosemary (Rosmarinus officinalis), and various species of mint (Mentha spp.). Other important sources are tropical trees, notably clove (Syzygium aromaticum) and cinnamon (Cinnamomum zeylanicum). Many of the essential oils have shown insecticidal, repellent, feeding deterrent (Jiang et al., 2010) and antimicrobial effects against a number of pests. Some of these oils or their constituents serve as active ingredients in commercially available insecticides, herbicides or repellents. Thymol, for example, a key essential oil constituent of garden thyme, is registered in Europe for the control of two important parasitic mites of the honey bee (Apis mellifera). Eugenol, a primary constituent of clove oil, is an active ingredient of a broad-spectrum insecticide (EcoPCO® D) sold by EcoSMART Technologies. Essential oil of rosemary is the active ingredient in two botanical insecticides currently used in the United States (HexacideTM and EcotrolTM).
We are also looking at the development of non-toxic crop protection chemicals that mimic naturally occurring bioactive odorants and tastants, and that are relatively easily prepared from commodity chemicals (Akhtar et al., 2010). We also look at the role of experience on the feeding behavior of larvae and oviposition choices of the subsequent moths with emphasis on habituation and dishabituation as well as learning and memory in insects (Akhtar et al., 2009). Cabbage looper (Trichoplusia ni), green peach aphids (Myzus persicae), confused flour beetles (Tribolium confusum), rust red flour beetle (Tribolium castaneum), and fruit flies (Drosophila melanogaster) are the major research insects. We also work with two-spotted spider mite (Tetranychus urticae). Bioassays are conducted to determine the feeding and oviposition deterrent effects of an essential oil. Feeding deterrent substances deter feeding in insects. Similarly, oviposition deterrent substances deter insects from laying eggs on the plants. Since insect damage to plants may result from feeding/oviposition or from transmission of pathogens during feeding, the chemicals that reduce pest injury by rendering plants unattractive or unpalatable may serve as potential substitutes for conventional insecticides.
References:
Akhtar, Y., Yu, Y., Isman, M.B., and Plettner, E. (2010). Dialkoxybenzene and dialkoxyallylbenzene feeding and oviposition deterrents against the cabbage looper, Trichoplusia ni: potential insect behavior control agents. Journal of Agricultural and Food Chemistry. 58: 4983-4991. DOI: 10.1021/jf9045123
Jiang, Z.L., Akhtar, Y., Zhang, X., Bradbury, R. and Isman, M.B. (2010). Insecticidal and feeding deterrent activities of essential oils in the cabbage looper, Trichoplusia ni (Lepidoptera: Noctuidae). Journal of Applied Entomology. DOI: 10.1111/j.1439-0418.2010.01587.x
Akhtar, Y., Shikano, I., and Isman, M.B. (2009). Topical application of a plant extract to different life stages of Trichoplusia ni fails to influence feeding or oviposition behaviour. Entomologia experimentalis et applicata. 132: 275-282.
Isman, M.B. (2008). Botanical insecticides: for richer for poorer. Pest Management Science 64:8-11.
One of the responsibilities I have at the Garden is looking after the library. After trying (and failing) to identify this plant, I ordered a copy of Ron Russo's Field Guide to Plant Galls of California and Other Western States for the library as a reference. Though it didn't help in that identification, the book has quickly become a favourite among the staff here at UBC Botanical Garden for its crisp photography and intriguing subject matter -- I think there will even be a book review in our next issue of Davidsonia.
The midge-induced gall on this Artemisia tridentata (big sagebrush) is not accompanied by a photograph in the book. However, Rhopalomyia medusa is mentioned in the image-accompanied entry on Rhopalomyia medusirrasa, a closely-related species. On Rhopalomyia medusirrasa, from the book:
"This midge induces globular, leafy-pubescent, polythalamous [many-chambered] galls on the bud of Great Basin sagebrush (Artemisia tridentata). These large galls are actually composed of numerous leaflife structures that are covered with long, forked hairs...Galls begin development in October, rest during the winter, and reach full size the following spring. These spring galls measure 20 to 25 mm in diameter and contain up to four larvae. Adults emerge in April or May. The larvae, pupae, and adults of this species [Rhopalomyia medusirrasa] are basically indistinguishable from those of Rhopalomyia medusa. The major differences exist with the galls. The galls of the woolly bud gall midge [Rhopalomyia medusirrasa] have the long white hairs, while the galls of Rhopalomyia medusa are hairless."
Gall midges are relatives of pests known to many indoor gardeners, fungus gnats (search the UBC BG Forums for "+fungus +gnat" (without quotes) to see the many discussions). For photographs of members of the genus Rhopalomyia, head on over to bugguide.net: Rhopalomyia. There are no images of either of Rhopalomyia medusa or Rhopalomyia medusirrasa, but you'll get a good sense of the various life stages of these small insect species from the others photographed.
I also note from this entry that I've never done an entry on Artemisia tridentata for BPotD. That's something I'll have to correct in the near future!
Heading out of the garden after an afternoon of taking photos, I was drawn to the intoxicating fragrance of Philadelphus delavayi, which was in full bloom. As I neared the shrub to drink in the aroma, I noticed this lovely butterfly busily feeding on the nectar from the flowers.
Ingrid Hoff, Horticulture Manager at UBC Botanical Garden and our resident insect specialist, identified it as Papilio rutulus, the western tiger swallowtail. She writes about the visitor, "This is one of the most common butterflies along the west coast, often found anywhere there is moisture. Large numbers of males can often be found "puddling" together in muddy areas or near streams. The species is found from British Columbia to Baja California east through the Rocky Mountains, but rarely beyond them. The western tiger swallowtail can have up to three broods per season.
Philadelphus delavayi has been feature on BPotD previously. Daniel Mosquin wrote this entry, which is still very much worth reading and the text accompanies a beautiful close up view of the buds and flowers.
The interpretive sign for this plant describes it very well:
"Named for the French missionary Père Jean Marie Delavay (1838-1895), who characterized much of the flora of Yunnan, Philadelphus delavayi is a variable species that is considered one of the most beautiful of all mock oranges.
Like other Philadelphus species, Delavay mock orange is an arching shrub that displays its pure white, saucer-shaped, fragrant flowers on short, lax racemes. The appeal of Philadelphus delavayi does not lie so much in its open flowers—which are admittedly large and beautiful—but in the sumptuous plum-purple calyces that back the flowers. The startling contrast of the purple calyx and white corolla is best seen before the flowers are completely open."
Today's images come to us from Suzan D. Suzan posted the photos for identification on the UBC Botanical Garden forums in 2004. She cleverly called these "woses." Original post.
Although the structure in the photo looks very much like a green rose, roses do not grow on willows. And while Suzan never found the insect, we believe this to be a gall caused by Rhabdophaga rosaria, the European rosette willow gall midge. Galls are abnormal growths found on plants that can be caused by parasites such as insects, mites, fungi or bacteria. Insects, particularly wasps and midges, are the most common cause of galls on plants. Plants form the galls in response to ovipositing or feeding by the insect, or from infection by another agent. The gall is an attempt to surround and isolate the invader. In the case of insects, the gall actually forms a protective chamber, where the larvae can develop safely away from predators.
Many types of galls exist. Many are shaped like balls or blisters. They are still unusual things to find in the garden, like this one from the UBCBG forums. In North America they are most commonly found on Fagaceae (oaks), but are also often found on Salicaceae (willows), Rosaceae (roses) and Asteraceae (asters). In general, they cause little damage to the plants and most are not considered to be significant pests.
Further reading on plant galls:
Abies religiosa is native to southern Mexico and western Guatemala at high altitudes: 2100m to 4100m (or thereabouts). According to the Gymnosperm Database entry for Abies religiosa, its common name of sacred fir is due to "its widespread use in Mexico to create decorations for use at religious festivals, especially Christmas", though others have suggested it is because the tips of the branches form a cross. The common name of oyamel fir tends to be more widely-used in popular texts about the species, particularly with regard to its ecology and its relationship with the monarch butterfly, Danaus plexippus.
The oyamel fir forests of Mexico are the wintering grounds for the monarchs of eastern North America, where the insects can be found in densities of 10 million individuals / hectare (4 million individuals / acre). While the species Abies religiosa itself is in no conservation danger, deforestation (ranging from illegal clearcut logging to thinning of trees -- see this documentary on illegal logging near the monarch reserves) is altering the ecological conditions of the oyamel fir forest such that the monarchs may one day no longer find suitable wintering habitat. Journey North explains the ecological requirements of the wintering monarchs in point form: The Monarch's Forest Ecosystem: Mexico's Oyamel Fir Forest. Simply put, deforestation is changing the humidity and temperature regime of the forest, such that the monarchs will not be able to meet their physiological requirements for wintertime survival.
You can learn more about monarch butterflies from these valuable sites: MonarchLIVE, the monarch butterfly page from Canadian Biodiversity (discusses threats and monarch migration) and Monarch Watch (blog) (these great folks also could use a little bit of financial help, if you're so inclined).
Ah, one last thing -- I apologize about the quality of the photographs. I forgot my polarizing filter for this trek to see the butterflies so the photographs have a lot of glare. I also wish I could've taken better photographs of the firs, but the butterflies kept getting in the way. Perhaps these videos I took will make up for it (one thing to note in the videos -- what appear to be solid masses of black shaded foliage are actually clusters of butterflies resting on the branches):
Today's entry is courtesy of Hannah Bottomley from Simon Fraser University, who has recently co-authored a paper on today's subjects. We've Hannah to thank for the write-up and thermographic images and Stephen Takács for the conventional photographs. Hannah writes:
Pinus monticola (western white pine) cones glow warmly in contrast to cool conifer needles in the infrared spectrum (top right; bottom left). Cones can be up to 15˚C warmer than needles (as indicated by the temperature bar on the right) and emit significantly stronger infrared radiation. Infrared radiation is a type of electromagnetic radiation that the human eye is unable to perceive; it has longer wavelengths than visible light (380-750 nanometres), but shorter wavelengths than microwaves (1 millimetre to 1 metre).
These thermographic images of Pinus monticola cones were taken with an infrared camera, exposing a previously unknown way in which insects are able to hone in on their host plant. Recent research by Takács and his colleagues reveals that Leptoglossus occidentalis (western conifer seed bug) has infrared receptors and is able to exploit the difference between cones and needles in the infrared spectrum, and zero in on cone-laden conifers from afar. This insect is a specialist herbivore that feeds on the contents of developing conifer seeds; in the second photo, it can be seen feeding on a Pinus monticola cone.
This phenomenon of warm cones is not limited to Pinus monticola - it has also been observed in Pinus contorta var. latifolia (lodgepole pine), Pseudotsuga menziesii (Douglas-fir), Picea engelmannii (Engelmann spruce) and Larix occidentalis (western larch). It is attributed in part to the fact that larger objects retain more heat than smaller objects, as well as to the tendency of a cone's surface to reflect solar radiation. In all likelihood, seed development (and associated metabolic activity) is also generating warmth, contributing to the relatively high temperature of conifer cones.
Although there are a few recognized infrared-detecting insects, this is the first study to show that herbivorous insects are using infrared emission from a specific part of a live plant as a foraging cue. This research is yet another testament to the complexity of plant-insect interactions and reminds us that there is a world of nature that exists beyond our own perception.
Daniel adds: For a popular summary of the paper, see "Heat Sensors Guide Insects to a Hot Meal" from ScienceNews. To view the scientific paper, see: Takács, S. et al. 2008. Infrared radiation from hot cones on cool conifers attracts seed-feeding insects. Proceedings of The Royal Society B. 276(1657):649-655. doi: 10.1098/rspb.2008.0742. For those of you who are particularly keen, I note that mast-seeding is mentioned in the abstract as a hypothesized method of producing a cone-crop large enough to exceed the capabilities of the insect herbivores to eat them all.
Horticulture / Garden Design link: Les jardins de Quatre-Vents, a garden I first learned about yesterday from the guide (thank you, Luana!) at Montréal Botanical Garden. Here are some photographs of the landscape and the plants. Virtual tours (in English) are available here: Virtual Tours of Les jardins de Quatre-Vents.
Thanks to Ruth for today's write-up and the first of the two photographs (I contributed the second). Ruth writes:
Today's BPotD is not of a plant but rather of the arthropod "anti-plant". The mountain pine beetle, Dendroctonus ponderosae, is a serious pest of the genus Pinus in British Columbia. Ponderosa (Pinus ponderosa), lodgepole (Pinus contorta), (the non-native) Scots (Pinus sylvestris) and limber pine (Pinus flexilis) are all attacked by this beetle. The adult beetles bore through the bark to the phloem (nutrient transport system) where they feed and lay eggs.
Outbreaks of this native beetle in North America have been experienced before, but this outbreak is an order of magnitude more severe than any previously recorded. Recent mild winters and an abundant food supply are considered to be the main cause of the explosion in beetle populations. British Columbia and Alberta apparently have the worst outbreaks, and these can be seen clearly from the air or on distant hillsides (in the second photograph) as reddish-brown patches through the forest. I took the first photograph in September along BC's Highway 5 to Kelowna.
This will be the second-last image in this pollinator series, as there are plenty of great non-pollinator images in the Flickr pool and the garden's BPotD submissions forum to share. Thanks to Eric in SF @Flickr for sharing today's photograph with us (original via Flickr BPotD Group Pool). Much appreciated, Eric, as always!
Passiflora caerulea, or passionflower, has previously been featured on BPotD -- but not with a honey bee! As stated by Eric on the Flickr page, this species is bee-pollinated. Wikipedia's entry on Passiflora mentions the pollinators of other species: "Some species can be pollinated by hummingbirds and bumble bees, others by wasps, still others are self-pollinating."
The University of Connecticut's Ecology & Evolutionary Biology Greenhouses have a page on Passiflora caerulea with horticultural information. Wayne Armstrong provides a brief summary of economic uses, religious symbolism and toxic properties of the genus in a small write-up on Passiflora.
The photographer behind today's image is Jack Dykinga, who I assume must have done some work for the USDA's Agricultural Research Service at one time (unless there are two exceptional photographers named Jack Dykinga). Artistic work commissioned by the US government has few restrictions on its reuse, and in this case, the photograph is licensed under the Creative Commons.
As noted on the above-linked page, this is a photograph of an Osmia ribifloris on a species of Berberis. The bee is commonly known as a blue orchard bee or, due to its success as a commercial pollinator of blueberry crops, the blueberry bee. In the wild, it is typically a pollinator of Californian manzanitas.
Wikipedia has an intriguing entry on Berberis (or barberry); the write-up for the genus includes details about the use of some species as spices or foods in Asia and South America. Somewhere around five hundred species of barberry are thought to exist, growing in temperate and subtropical regions of most continents except Australia (and, it goes without saying, Antarctica).
Note: this entry was rewritten on Sept. 23, 2008 due to a misidentification. Thanks to David (see comments below) for the correct ID.
Broad-flowered or hollyleaf gilia is an annual plant. A California endemic, it is found in the southern portion of the state in the southwestern Mojave Desert and adjacent foothills. These photographs were taken while I was developing the worst sunburn of my life in late March. This was thanks in part to the cool winds that gust through the Antelope Valley from the nearby mountains in spring, which deceived me into believing I wasn't being slowly roasted by the sun.
The closely-related species (and the name of my original, incorrect identification) Gilia tricolor is a popular annual ornamental, if search engine results are any indication. For a comparison between the correct identification and my original misidentification, Calphotos provides an extensive set of photographs of both Gilia latiflora subsp. davyi and Gilia tricolor.
As for the insect in today's photograph, I believe it is Hyles lineata (source: Butterflies and Moths of North America Database), or the white-lined sphinx. Wikipedia has some photographs of the larvae (caterpillars), as does this site. While many moths are nocturnal, it is noted that the white-lined sphinx will often be active during the day (and this one was plenty active!). I think I've linked to it before, but if you haven't seen the US Forest Service's site on Celebrating Wildflowers, it is worth investigating. They even have a section on moth pollination.
Let's start a little series on plants and pollinators, and see where that takes us. I can't guarantee I'll be able to identify all of the pollinators, but maybe some kind folks will identify and comment.
In this case, I believe this Sitka valerian is being visited by a hoverfly, a fairly common pollinator of plants. While population declines in pollinator groups such as bees and vertebrates get some press, the conservation status and potential effect of a decline in dipterans (flies and mosquitoes) is poorly understood (see: Kearns, C.A. 2001. North American dipteran pollinators: assessing their value and conservation status. Conservation Ecology 5(1): 5). Unfortunately, that likely isn't going to change soon, if this quote from the discussion section of that paper remains true:
"An attempt to document the conservation status of fly pollinators in North America reveals the need for further basic research into fly pollination systems, and into the natural fluctuations in dipteran abundance. The main impediment to implementing any of the large-scale studies recommended is that intensive collecting efforts produce large numbers of species that require identification. Fly species identifications are often difficult, and the number of fly taxonomists is limited."
Sitka valerian is native to western North America, where it is typically a plant of mid- to high-elevations in moist meadows and open subalpine forest. In some areas of the Thynne Mountain, where this photograph was taken, it was the dominant herbaceous species. Plants of Southern Interior British Columbia notes that First Nations groups often used the plant as a medicine or disinfectant.
Ask most people about the various kinds of flower pollinators and the first responses you are likely to get are bees and butterflies. Beetles, however, are also important pollinating organisms. One site uses the figure of beetles contributing to the population of up to 88% of the world's flowering plants (source: Beetle Pollinators via the USDA's Pollinators site), though I haven't been able to find a scientific reference to back up that number (and considering the number of exclusively bee-, butterfly-, moth-, bat-, wind- and water-pollinated plants, I find it a bit hard to believe). Beetle pollination is scientifically known as cantharophily, coincidentally named after the soldier beetle family, Cantharidae, to which the beetle in today's photo belongs.
My observations, later verified upon researching, were that this beetle is an incidental pollinator. In its quest for seeking out small edible insects, the common red soldier beetle (photo in flight | Wikipedia) inserts its head into the diminutive flowers and brushes up against the anthers. Pollen sticks to the head of the beetle and is subsequently transferred to other flowers as it continues its grazing behaviour. In the span of ten minutes, I observed this beetle visiting approximately twenty flowers — quite a pace!
Rhagonycha fulva is often found on members of the Apiaceae, or umbel family, like the plant in today's photograph: Foeniculum vulgare, or fennel (previously featured on BPotD here with a link to Gernot Katzer's spice page on fennel). Interestingly, Gernot Katzer notes that it is not only the fruits of fennel that are used in cuisine; the pollen of fennel (aka “Spice of the Angels”) is a small-scale exotic (and expensive) herb crop in Italy and California. If only the beetles could be trained...
Lastly, thank you to both BugGuide and What's That Bug? for enabling me to identify the beetle.
Today's image is courtesy of Janet Davis, garden writer extraordinaire and author of the Beautiful Botany web site (previously featured as a resource link). Janet used this image of butterfly milkweed and a monarch butterfly to illustrate her article on butterfly plants. Please keep in mind that the usual copyright terms apply to this image since it is from someone not employed by UBC Botanical Garden. Thank you, Janet!
As mentioned in a previous entry, milkweeds are the exclusive food of monarch butterfly caterpillars. Toxins in the milkweed sap accumulate in the tissue of the caterpillar, rendering it (and the subsequent adult) poisonous and inedible to birds.
Asclepias tuberosa has two features that distinguish it from other milkweeds: 1) its sap is not milky, and 2) its leaves are alternately arranged, instead of opposite. The Shenandoah National Park in the US has an excellent factsheet on Asclepias tuberosa for more information.
On a final note, monarchs have been in the news and editorials recently regarding an international agreement to conserve monarch habitat. “Is the mighty monarch butterfly on its last wings?” is an editorial questioning the utility of the agreement in the face of other dangers to the monarch.
Photography resource link: The Making of a Fine Art Photograph, an article by Pete Myers for The Luminous Landscape web site. It examines the process and time spent in “digitally developing” an image for fine art after pressing the shutter.
Zinnia haageana 'Old Mexico' is an All-America Selections Winner from forty-three years ago –, a cultivar that has stood the test of time. Considering its performance in trials done by The Gardens at the University of Georgia, that decades-long popularity is no wonder. It has performed similarly well this year at UBC.
Autographa californica is the moth, commonly known as the alfalfa looper. The sickle-shaped white spot on the wing is an easy diagnostic feature.
The adult moth does no damage, while the caterpillar is rarely present in numbers large enough to have an economic impact on crops. In fact, the University of California Integrated Pest Management Program for cotton and loopers states: “Moderate populations of loopers may be more beneficial than harmful, as they support populations of natural enemies that also attack the more destructive bollworms, budworms, and beet armyworms.”. Similar statements are made on the site regarding loopers and other Californian crops such as lettuce, artichoke and tomatoes. Along with a suite of predators, alfalfa looper is also susceptible to a baculovirus.
Botany / conservation resource link: Botanic Gardens Conservation International “brings together the world's botanic gardens to work for plant conservation through science, education and horticulture.”
