Fri, 25 May 2007 05:16:01 GMT

Palouse Hills

The Palouse area of eastern Washington and north central Idaho elicits mixed feelings in me. As an admirer of topographic form, the rolling hills are a delight to discover and explore. At this time of year, combinations of earthy browns and greens (with splashes of verdant green from newly-emerged seedlings) dominate the landscape under dusty blue skies. In June, the earthier tones make way for the multiple shades of green of different crops under clear blue skies. Harvest gold, of course, follows in the autumn. It is the most beautiful cultivated landscape I've ever observed in person.

The structure of the landscape is the result of wind-blown silt (loess), deposited during the ice ages. Similar to riparian silt deposits, it is very fertile soil and conducive to intensive farming.

It is difficult for me, however, to suppress imagining what the landscape would have looked like two hundred years ago, when the hills were a far-reaching prairie covered with Pseudoroegneria spicata (bluebunch wheatgrass) and Festuca idahoensis (Idaho fescue). The area, however, suffered the same fate of most North American prairie. Only remnant patches of original prairie remain where some rare (and endangered) endemics can be found, like Calochortus nitidus (broadfruit mariposa lily) and Driloleirus americanus, the giant Palouse earthworm (thought to have been extinct by the 1980s, most recently seen in 2005).

Wikipedia's entry on the Palouse region provides some area history and the environmental changes brought about by agriculture.

The Palouse Prairie Foundation “promotes preservation and restoration of native Palouse Prairie ecosystems in Latah and Whitman Counties (in Idaho and Washington), through public awareness, education, literature resource, encouraging responsible local seed production, and acting as a leader or consultant in Palouse Prairie restoration efforts.”. Posted by: Daniel Mosquin      Read more     Source

May 17, 2007, 7:28 PM CT

Colorado River streamflow history

An epic drought during the mid-1100s dwarfs any drought previously documented for a region that includes areas of Arizona, Colorado, New Mexico, Utah and Wyoming.

The six-decade-long drought was remarkable for the absence of very wet years. At the core of the drought was a period of 25 years in which Colorado River flow averaged 15 percent below normal.

The new tree-ring-based reconstruction documents the year-by-year natural variability of streamflows in the upper Colorado River basin back to A. D. 762, said the tree-ring researchers from The University of Arizona in Tucson who led the research team.

The work extends the continuous tree-ring record of upper Colorado streamflows back seven centuries earlier than prior reconstructions.

"The biggest drought we find in the entire record was in the mid-1100s," said team leader David M. Meko, an associate research professor at UA's Laboratory of Tree-Ring Research. "I was surprised that the drought was as deep and as long as it was.

Colorado River flow was below normal for 13 consecutive years in one interval of the megadrought, which spanned 1118 to 1179.

Meko contrasted that with the last 100 years, during which tree-ring reconstructed flows for the upper basin show a maximum of five consecutive years of below-normal flows......... Posted by: Tyler      Read more         Source

Tue, 08 May 2007 02:21:04 GMT

Lupinus onustus (tentative)

A weekend trip to central northern Oregon and southern Washington yielded more than a few photographic opportunities. The wildflowers were out in abundance on both sides of the Columbia River. I found Paul Slichter's Wildflower Viewing Areas in the Columbia River Gorge and Currently Blooming Wildflowers in Oregon & Washington to be invaluable guides in planning the trip.

Paul prefers the name Lupinus latifolius var. thompsonianus for this taxon; if treated as such, it is a Columbia River Gorge endemic, found only on low- to mid-elevation hillsides bordering on a 70km (40mi) stretch of the river. The Integrated Taxonomic Information System, however, synonymizes this variety with Lupinus onustus, a species with a broader range as it is also found in California. The USDA PLANTS database, which nearly always complies with ITIS, suggests a different name. It lists this entity as Lupinus sericeus subsp. sericeus var. thompsonianus. To add to the confusion, the range maps for both Lupinus sericeus subsp. sericeus var. thompsonianus and Lupinus onustus in the PLANTS database exclude Washington state, where this photograph was taken.

Have I mentioned yet that the taxonomy of Lupinus is confusing? “In the New World, Lupinus is notorious for being a very complex and difficult genus. Taxonomic confusion exists in the literature, where numerous taxa or groups are distinguished based on only a few minor and inconsistent morphological characters. Over 1700 names have been proposed for Lupinus. Approximately 200 species clustered in 18 groups were suggested by Smith (1944) for North America. Taking into account new evidence from various approaches, it became clear to modern authors that the complexity of this genus resulted from its high morphological, breeding system, and ecogeographical diversity and the lack of clear diagnostic features to separate species” (quoted from the opening paragraphs of Ainouche, A-K and R. Bayer. 1999. Phylogenetic relationships in Lupinus (Fabaceae: Papilionoideae) based on internal transcribed spacer sequences (ITS) of nuclear ribosomal DNA. Am. J. Bot. 86:590-607.). Posted by: Daniel Mosquin      Read more     Source

Sun, 11 Mar 2007 15:39:38 GMT

Helleborus ×hybridus

Well, it turns out I was a bit premature in declaring that spring had arrived – this photograph is from last Thursday morning, when a fresh blanket of snow covered the garden. Fortunately, it didn't dip much below freezing, so little damage was done to the plants. The cold weather continues to push back the date for the first magnolia blossoms, though. Last year, the first flowers emerged in late February. I suspect it will be at least three more weeks before that noteworthy event occurs.

As for the rest of this entry, please see the accompanying comments regarding an incorrect identification.

Viridis means green, hence the common name of green hellebore for this species. It is one of many hellebore species and cultivars presently in bloom at the garden. You would have to visit the Winter Garden to see most of them, though today's plant is found elsewhere – it grows in the European section of the Alpine Garden, where its label further notes that it is native to western and central Europe. A map of the native distribution of the species can be found on Joseph Woodard's Hellebores.org web site as part of the factsheet for Helleborus viridis (there's also a good photograph of the plant's fruit, termed a follicle). It is also found in the wild elsewhere as an introduced plant, including eastern North America.

As noted by the Plants for a Future Database, All parts of this plant are poisonous, like so many other members of the Ranunculaceae (noted in the recent entry on Eranthis, as well).

Posted by: Daniel Mosquin      Read more     Source

Sun, 04 Mar 2007 17:51:15 GMT

Purshia mexicana

A thank you to Jon of SMA@Flickr for today''s photograph (original image | Flickr BPotD Group Pool). The SMA in Jon''s Flickr ID stands for San Miguel de Allende, a historic town in Guanajuato, Mexico – a place which has been very much on my mind lately. I''ve bookmarked Jon''s weblog, San Miguel Photos.

In his notes accompanying the photograph, Jon wrote that the common name for this plant in Mexico is romero cedro. After much searching, I did track down a reference for the name, the Flora Del Bajío Y De Regiones Adyacentes - Rosaceae, or the Flora of Bajío and Adjacent Regions - Rosaceae (Bajío is a region of plains in northern central Mexico). The common name of romero cedro actually applies to two species: Purshia plicata and Purshia mexicana (and presumably the hybrid between the two). Despite my limited ability to translate Spanish, it is quite evident this is Purshia mexicana, as it has white to yellowish flowers (instead of pink) and deeply-lobed leaves. There is a beautiful pencilled rendition of the flowers on a branch on page 115 of the flora, if you are patient enough for the file to load.

The English common name for this plant is Mexican cliffrose (or antelope bush). Following current taxonomy, it is native from Arizona to northern central Mexico, occupying the southern portion of this genus'' distribution. A closely related species, Purshia stansburiana is sometimes classified as a subspecies of Purshia mexicana. If that treatment is followed, the range of Purshia mexicana extends as far north as Idaho. A different species, Purshia tridentata, reaches the northern limits for Purshia in the southern interior of British Columbia – expect a photograph of this species in late May after I attend Botany BC 2007 in Osoyoos. I find Purshia to be very photographically appealing due to its architecture.

Posted by: Sandra      Read more     Source

January 31, 2007, 9:04 PM CT

Continuing Tomato Sequence Project

An international project led by Cornell and the Boyce Thompson Institute for Plant Research (BTI) at Cornell has received $1.8 million from the National Science Foundation (NSF) to continue sequencing the tomato genome and to create a database of genomic sequences and information on the tomato and related plants.

The grant for the International Tomato Sequencing Project, a collaboration of scientists from nine other countries, will enable U.S. scientists to continue their work. In 2004 the NSF provided $4 million for the U.S. part of the research.

Sequencing the tomato genome is the first step in creating the comprehensive International Solanaceae Genomics Project (SOL) Genomics Network database. This will tie together maps and genomes of all plants in the Solanaceae family, also called nightshades, which includes the potato, eggplant, pepper and petunia and is closely correlation to coffee from the Rubiaceae family.

The public database will help scientists ask fundamental questions: Have changes from a common ancestor brought about the attributes of crop species? What are the functions of specific genes? How has domestication changed genes? Which plants might be good candidates for genetically engineered improvements for growing crops?

Cornell scientists are close to completing a toolkit of resources about tomato and solanaceae species (some currently available in the database) to make the sequencing possible. These resources include genetic maps, DNA libraries, individual gene sequences, DNA markers and associated information, comparative mapping data to go from one species to another as sequences are added, and tools to query and search this information.........

Posted by: Jessica      Read more         Source

January 24, 2007, 7:40 PM CT

deep-sea fauna under Antarctic ice shelf

Under the former Larsen ice shelf east of the Antarctic Peninsula, deep-sea sea cucumbers and stalked feather stars were ubiquitously found in shallow waters. These animals usually inhabit far greater water depths.

The main aim of the current Polarstern expedition to Antarctica is the investigation of marine ecosystems under the former Larsen ice shelf. This "white spot" with regard to biodiversity research gave rise to the following questions: What kind of life actually existed under the former floating ice shelf which was up to several hundreds of meters thick? What are the prospects for the future after the collapse of the ice shelf? Obviously, prosperous life did not exist in the area where the Larsen B ice shelf broke off three years ago. This is surprising since Antarctica's seafloor communities are known for their rich assemblages of sessile sponges, cnidarians and moss animals. Instead, underwater video footage and catches of towed sampling gear revealed the dominance of typical deep-sea animals and corresponding life forms.

Here, sea cucumbers and stalked feather stars are the main representatives. These deep-sea inhabitants belong to a group called echinoderms. Until now, stalked feather stars have only been found sporadically and then only below 800m water depths in this sector of Antarctica. But locally in the Larsen B region, they occurred rather frequently at depths of merely 200m. "During my nine expeditions to Antarctica, the only time I have seen the two most abundant species of sea cucumbers was below the far bigger Filchner-Ronne ice shelf further south." This second encounter brought back chief scientist Julian Gutt's memories of his first trip to Antarctica and his PhD thesis 21 years ago. Preliminary results show that a unique macrofauna exists in conjunction with the ice shelf. The sea cucumber Elpidia is probably the most prominent deep-sea animal but is also known to occur in shallow Arctic waters. Maybe this is the reason why this animal is aptly named glacialis (icy) especially with regard to our confirmatory findings on the opposite pole - Antarctica.........

Posted by: Ashley      Read more         Source

January 15, 2007, 9:27 PM CT

Molecular Differences Between Rice And Its Mimic

Red rice sounds like a New Orleans dish or a San Francisco treat. But it's a weed, the biggest nuisance to American rice growers, who are the fourth largest exporters of rice in the world. And rice farmers hate the pest, which, if harvested along with domesticated rice, reduces marketability and contaminates seed stocks.

Complicating matters is the fact that red rice and cultivated rice are exactly the same species, so an herbicide cannot be developed that seeks out only red rice. It would kill cultivated rice, too.

But now a plant evolutionary biologist at Washington University in St. Louis has been funded by the National Science Foundation (NSF) at $1.12 million for two years to perform genetic studies on red rice to understand molecular differences between the two that someday could provide the basis for a plan to eradicate the weed. The particular NSF program funding the research is the Plant Genome Comparative Sequencing Program.

Kenneth M. Olsen, Ph.D., Washington University assistant professor of biology in Arts & Sciences, believes that gene flow is one factor that has been at work.

"We are looking for candidate genes that underlie particular traits that differ between the two," said Olsen. "Knowing more about the traits could help in potentially controlling the weed. We have a key advantage in this research in that we know the complete cultivated rice genome, so it's fairly easy to target genes of interest."........

Posted by: Jessica      Read more         Source

January 15, 2007, 7:32 PM CT

Rubus thibetanus 'Silver Fern'

This bramble is the source of much recent photographic frustration for me. It beckons outside my second-floor office window with its tangled icy-blue mass of canes, asking to be photographed in pretty much the exact frame that I see through the window from my office chair - a window that only opens thirty degrees outwards, thereby requiring me to either 1) move furniture and lean out the window while undergoing unnatural contortions (which I suspect the safety folks might have something to say about); 2) take the photograph through the window glass (and accept some glare and reduced image quality); or 3) let it taunt me. I wonder if I can get away with propping a ladder against the side of the building.

This shot was from a much closer distance, with a new lens.

By Daniel Mosquin.........

Posted by: Jessica      Read more         Source

January 12, 2007, 5:03 AM CT

Soil Nutrients Shape Tropical Forests

Tropical forests are among the most diverse plant communities on earth, and researchers have labored for decades to identify the ecological and evolutionary processes that created and maintain them. A key question is whether all tree species are equivalent in their use of resources - water, light and nutrients - or whether each species has its own niche.

A large-scale study by scientists at the University of Illinois at Urbana-Champaign and eight other institutions sheds some light on the issue. It indicates that nutrients in the soil can strongly influence the distribution of trees in tropical forests. The finding, published this week in the Proceedings of the National Academy of Sciences, challenges the theory that at local scales tree distributions in a forest simply reflect patterns of seed dispersal, said James W. Dalling, a U. of I. professor of plant biology and a principal researcher on the study.

The study reviewed three sites: two lowland forests, in central Panama and eastern Ecuador, and a mountain forest in southern Colombia. The scientists plotted every tree and mapped the distribution of soil nutrients on a total of 100 hectares (247 acres) at the sites. The study included 1,400 tree species and more than 500,000 trees.

The scientists compared distribution maps of 10 essential plant nutrients in the soils to species maps of all trees more than 1 centimeter in diameter. Each of the sites was very different, but at each the scientists found evidence that soil composition significantly influenced where certain tree species grew: The spatial distributions of 36 to 51 percent of the tree species showed strong associations with soil nutrient distributions.........

Posted by: Jessica      Read more         Source