June 10, 2009, 9:41 PM CT

Reviving American chestnuts may mitigate climate change

A Purdue University study shows that introducing a new hybrid of the American chestnut tree would not only bring back the all-but-extinct species, but also put a dent in the amount of carbon in the Earth's atmosphere.

Douglass Jacobs, an associate professor of forestry and natural resources, observed that American chestnuts grow much faster and larger than other hardwood species, allowing them to sequester more carbon than other trees over the same period. And since American chestnut trees are more often used for high-quality hardwood products such as furniture, they hold the carbon longer than wood used for paper or other low-grade materials.

"Maintaining or increasing forest cover has been identified as an important way to slow climate change," said Jacobs, whose paper was reported in the recent issue of the journal Forest Ecology and Management "The American chestnut is an incredibly fast-growing tree. Generally the faster a tree grows, the more carbon it is able to sequester. And when these trees are harvested and processed, the carbon can be stored in the hardwood products for decades, maybe longer".

At the beginning of the last century, the chestnut blight, caused by a fungus, rapidly spread throughout the American chestnut's natural range, which extended from southern New England and New York southwest to Alabama. About 50 years ago, the species was nearly gone......... Posted by: Erica      Read more         Source

May 24, 2009, 8:53 PM CT

Thanks to spillover from landscape corridors

Recently, images of melting sea ice and shrinking rainforests have highlighted the world's biodiversity crisis and made us aware of the need to find a balance between preserving natural ecosystems while still having enough land for human use.

"About 10 percent of the world's land surface is afforded formal protection. We need to manage that 10 percent as best as we possibly can to preserve biodiversity but also be mindful of human needs, such as food and fiber production," said Lars A. Brudvig, Ph.D., post-doctoral researcher in biology in Arts & Sciences at Washington University in St. Louis.

"One way to do this is by managing the land in a way that promotes biodiversity beyond the habitat's borders."

One of the most popular ways to manage landscapes fragmented by humans is to connect the isolated patches of habitat with skinny strips of land called corridors.

Brudvig and Ellen I. Damschen, Ph.D., assistant professor of biology at Washington University, in collaboration with scientists at the University of Washington, North Carolina State University and University of Florida, have discovered that the biodiversity in a patch of habitat can extend outside the borders of a protected area; this effect is magnified when the habitats are connected by corridors......... Posted by: Erica      Read more         Source

April 22, 2009, 10:11 PM CT

Plants could override climate change effects on wildfires

Researchers predict that global climate change will make a number of regions around the world warmer and drier, a factor which, taken by itself, would seem to increase the risk of wildfires.

But a newly released study led by a Montana State University researcher shows that changes in the types of vegetation covering an area play a major role in determining how often that area is burned by fires and could even counteract the effects of changes in temperature and moisture.

In the study, MSU earth sciences post-doctoral researcher Philip Higuera and colleagues show that the risk of wildfires can be either reduced or increased by changes in the distribution and abundance of plants. The study would be reported in the recent issue of the journal Ecological Monographs.

"Climate affects vegetation, vegetation affects fire and both fire and vegetation respond to climate change," Higuera said. "Our work emphasizes the need to consider the multiple drivers of fire regimes when we anticipate how they will respond to climate change."

Higuera and colleagues studied fire history in northern Alaska by analyzing sediments at the bottom of lakes, some dating as far back as 15,000 years. In the samples from the lakes, the researchers measured the abundance of different preserved plant parts, such as pollen, to determine what types of vegetation dominated the region in the past. Like rings in a tree, different sediment layers represent different times in the past......... Posted by: Erica      Read more         Source

April 20, 2009, 5:15 AM CT

Antioxidant benefits of tart cherries

Eating just one and a half servings of tart cherries could significantly boost antioxidant activity in the body, according to new University of Michigan research reported at the 2009 Experimental Biology meeting in New Orleans.¹ In the study, healthy adults who ate a cup and a half of frozen cherries had increased levels of antioxidants, specifically five different anthocyanins the natural antioxidants that give cherries their red color.

Twelve healthy adults, aged 18 to 25 years, were randomly assigned to eat either one and a half cups or three cups of frozen tart cherries. Researchers analyzed participants' blood and urine at regular intervals after they ate the cherries and found increased antioxidant activity for up to 12 hours after eating cherries.

"This study documents for the first time that the antioxidants in tart cherries do make it into the human bloodstream and is coupled with increased antioxidant activity that could have a positive impact," said Sara L. Warber, MD, Co-Director of University of Michigan Integrative Medicine and principal investigator of the study. "And, while more research is needed, what's really great is that a reasonable amount of cherries could potentially deliver benefits, like reducing risk factors for heart disease and inflammation." ......... Posted by: Erica      Read more         Source

April 6, 2009, 9:32 PM CT

Male flower parts responsible for potent grapevine perfume

University of British Columbia researchers have traced the fragrant scent of grapevine flowers to pollen grains stored in the anthers, contrary to common perception that petals alone produce perfume.

While studying grapes used to produce Cabernet Sauvignon from the Okanagan region of British Columbia, scientists from UBC's Wine Research Centre and Michael Smith Laboratories identified a gene that produces and regulates fragrance from the vines' tiny clusters of green blossoms.

"This was a surprise in fundamental plant biology," says Joerg Bohlmann, a Distinguished University Scholar and professor in the Michael Smith Laboratories who directed the study. "This discovery gives us strong clues to the origin and evolution of fragrant flowers".

Details of the study are published in this week's Proceedings of the National Academy of Sciences Online Early Edition.

Researchers believe plants have evolved to produce perfume in order to attract specific types of pollinators while fending off herbivores and pathogens.

"If you ask people where the perfume of a flower comes from, they'll likely say the female parts or the petals," says Bohlmann. While flowers such as roses and snapdragons rely on their petals to produce perfume and attract insects, few other species have been so closely studied......... Posted by: Erica      Read more         Source

April 2, 2009, 5:07 AM CT

Tropical forest seed banks

Seeds of some tree species in the Panamanian tropical forest can survive for more than 30 years before germinating.

That is 10 times longer than most field botanists had believed.

Using the Lab's Center for Accelerator Mass Spectrometry to measure the amount of carbon 14 in seeds of the trees Croton billbergianus (Euphorbiaceae), Trema micrantha (Celtidaceae) and Zanthoxylum ekmannii ( Rutaceae), Lawrence Livermore National Laboratory scientist Tom Brown and University of Illinois at Urbana-Champaign colleague James Dalling observed that seeds survived in the soil for 38, 31 and 18 years, respectively.

Prior demographic studies of pioneer tree species showed that seed persistence (the ability to survive in soil, awaiting favorable conditions for germination) is short, lasting only for a few years at most.

But in the tropical forests of Barro Colorado Island (BCI), Panama, Brown and Dalling found the seeds of some pioneer trees remain viable for a number of years.

"This is part of nature that wasn't really what people in the field thought was going on," Brown said. "It turns out these seeds in soil just a few centimeters below the surface can survive a lot longer than anyone ever thought was possible".

To increase the probability of encountering "old" seeds, Brown and Dalling used data from a forest plot to target sites in the forest occupied 20 years previously by species they suspected were capable of long-term persistence......... Posted by: Erica      Read more         Source

March 25, 2009, 9:45 PM CT

Who influences purchases of native plants?

Native plants are a growing niche market in the southeastern United States. Scientists have documented recent trends toward increased interest in native plants by landscape architects, wholesale and retail nursery owners, and home gardeners. But landscape professionals and amateur gardeners purchase native plants for distinctly different reasons. Statistics reveal that landscape architects most often select native species because they are suited to difficult or unique growing conditions, while retail plant buyers purchase native plants based on recommendations from landscape architects and contractors.

If landscape architects are the primary drivers of native plant sales in the southeastern United States, what impact does that have upon wholesale nursery growers and the retail market? What is the potential of the native plant market in this region, and what are the best ways of fostering its growth? To answer these questions, Robert F. Brzuszek and Richard L. Harkess, scientists at Mississippi State University, developed an e-mail survey for wholesale and retail nursery owners (members of the Southern Nursery Association) in the southeastern region of the United States. The survey results and recommendations were reported in the latest issue of the American Society for Horticultural Science journal HortTechnology........ Posted by: Erica      Read more         Source

March 25, 2009, 9:39 PM CT

Alternatives to pine bark and peatmoss identified for commercial, home gardens

Pine bark and peatmoss are the two most common substrates used for horticultural crop production in the southeastern United States, but both media can present challenges to growers. Reduced forestry production and increased use of pine bark as fuel and landscape mulch has made the medium less available, while the price of peatmoss is rising due to transportation costs and growing environmental concerns over the mining of peat bogs in Canada and Europe. These and other factors have contributed to a demand for new alternative substrates for container production of horticultural crops.

The use of agricultural waste and other composted materials is not a new concept, but factors such as consistency and reproducibility of product, disease and insect infestation, and availability of composted materials often influence growers' decisions regarding the use of these materials.

Alternative substrates grown from wood and wood-based products have been investigated as suitable substrates or substrate components in nursery and greenhouse crop production. European research has resulted in numerous successful commercialized wood substrates. More recently, a pine tree substrate called WoodGro has been developed from ground whole loblolly pine logs to successfully produce a wide range of nursery and greenhouse crops......... Posted by: Erica      Read more         Source

March 25, 2009, 9:37 PM CT

What influeces floral purchase

Scientific studies of "consumption value" explore the reasons consumers choose particular products and provide marketers with ways to analyze consumer behavior and influence purchasing. Studying the value of consumption is believed to have diagnostic value in the analysis of consumer choice behavior and, therefore, is helpful in improving the efficiency of the market. To enhance efficiency and promotion, it is essential for marketers to know the consumption value that buyers place on products.

Tzu-Fang Yeh and Li-Chun Huang from Da-Yeh University in Changhua, Taiwan, and National Taiwan University, Taipei, Taiwan, recently published a research report in the American Society of Horticultural Science journal HortTechnology The study's objective was to identify the consumption value that consumers seek from floral products, while clarifying the context of these values.

Men and women from three main cities in Taiwan were sampled to represent a population living an urban lifestyle. To compare differences in the consumption values, both genders of consumers from rural areas also participated in the survey. From a consumer survey of 33 questions, 644 valid questionnaires were analyzed.

The researchers discovered that "the statistical results of the analysis revealed that sensory hedonics, emotion conditioning, curiosity fulfillment, monetary worth, and showing care to others were the main types of the consumption values related to floral products"......... Posted by: Erica      Read more         Source

March 24, 2009, 6:21 AM CT

Small investments to battle soybean pest paying off big

The small amount of money put toward fighting the tiny, yet destructive soybean aphid will pay big dividends in the coming years, said a Michigan State University economist, thanks to a research and outreach system developed during the last 50 years.

State and federal governments have spent $17 million on soybean aphid research and education since 2003, MSU agricultural, food and resource economics professor Scott Swinton said. The net economic benefit of that integrated pest management work, or IPM, should reach $1.3 billion during the next 15 years, he said. That's an annual rate of return of 180 percent.

"This is an example of what a good payoff you can get as a result of long-term research," Swinton said. "There's been a half century of research into integrated pest management. In the process a lot of techniques were developed and lots of understanding was gained about the relationships between crop and pest life cycles, infestations and the weather to decide when it's necessary to control them without wasting money and creating health risks".

Integrated pest management "takes a comprehensive approach to pest management that balances economics with environmental and human safety, as well as with what makes sense on the ground in the local community," said Michael Brewer, MSU's IPM Program coordinator......... Posted by: Erica      Read more         Source