The bacteria in and on our bodies have been shown to be vital for human health, influencing nutrition, obesity and protection from diseases.

But science has only recently delved into the importance of the microbiome of plants. Since plants can’t move, they are especially reliant on partnerships with microbes to help them get nutrients.

Now, ÌìÃÀÓ°ÊÓ´«Ã½ plant microbiologist , along with her team of undergraduate and graduate students and staff, has demonstrated that poplar trees growing in rocky, inhospitable terrain harbor bacteria within them that could provide valuable nutrients to help the plant grow. Their , which could have implications for agriculture crop and bioenergy crop productivity, were published May 19 in the journal .

The researchers found that microbial communities are highly diverse, varying dramatically even in cuttings next to each other.

“This variability made it especially difficult to quantify the activity, but is the key to the biology since it is probably only specific groupings of microorganisms that are working together to provide this nutrient to the host,” said Doty, a professor in the UW .

is a natural process that is essential to sustain all forms of life. In naturally occurring low-nutrient environments such as rocky, barren terrain, plants associate with nitrogen-fixing bacteria to acquire this essential nutrient.

It’s well documented that nitrogen fixation happens in bacteria-rich nodules on the roots of legumes such as soybeans, clovers, alfalfa and lupines. Bacteria help the roots fix atmospheric nitrogen gas into a form which can be used by the plant.

There is a strongly held belief that only plants with root nodules can benefit from this type of symbiosis. This research provides the first direct evidence that nitrogen fixation can occur in the branches of trees, with no root nodule required.

This could have significant implications for common agricultural crop plants. The microbes the team has isolated from wild poplar and willow plants help corn, tomatoes and peppers, as well as turf grasses and forest trees to grow with less fertilizer.

Fertilizers are synthesized using fossil fuels, so costs can fluctuate wildly. Because fertilizers are used for growing everything from agricultural and bioenergy crops and trees for lumber to the grass in golf courses, this volatile pricing and uncertain availability affects everyone.

“Having access to the key microbial strains that help wild plants thrive on just rocks and sand will be crucial for moving agriculture, bioenergy and forestry away from a dependence on chemical fertilizers and towards a more natural way of boosting plant productivity,” Doty said.

The researchers plan to work with the Pacific Northwest National Laboratory to try to find out exactly which microbes are doing the most work in the wild trees.

Other co-authors are Andrew Sher, Neil Fleck, Mahsa Khorasani, Zareen Khan, Andrew W. K. Ko, Soo-Hyung Kim and Thomas DeLuca of the UW’s School of Environmental and Forest Sciences; and Roger Bumgarner of the UW’s Department of Microbiology.

This research was funded by the U.S. Department of Agriculture and the Byron and Alice Lockwood Professorship.

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For more information, contact Doty at sldoty@uw.edu.

John Freeman, chief scientific officer of Intrinsyx Technologies, is working with the organic farming community to bring this science to application. The company has licensed many of microbes described in this paper and is currently working toward commercializing them. Contact Freeman at jfreeman@intrinsyx.com for more information.

Grant information: Agriculture and Food Research Initiative (USDA); grant #2010-05080

The two professions historically didn’t see eye to eye, but Franklin, in his current role as a UW professor of environmental and forest sciences and previously as a forester with the U.S. Forest Service, has in his 60-year career found a way to integrate ecological and economic values into forestry. He is now a world-renowned leader in sustainable forest management.

The Washington, D.C.-based recently awarded Franklin its , which honors “an individual who has made extraordinary and valuable contributions to science or practice in environmental conservation and sustainable natural resources management.” The award is named for Gifford Pinchot, the first leader of the U.S. Forest Service and an advocate for conservation.

With the award, Franklin was invited to give a distinguished lecture to members of the , a private club in D.C. whose members include political and scientific leaders. Among the many awards he has collected, this one is particularly significant, he said.

“I’ve always felt like I was too much of an ecologist for the foresters, and too much of a forester for the ecologists. This really indicated to me that, yes, I’ve had a big impact in forestry,” Franklin said.

“It recognizes me both for the science and the role I’ve had in seeing that science incorporated into policy. Our whole perspective on forests has changed in 60 years, essentially the span on my career.”

Franklin started his career with the Forest Service’s Pacific Northwest Research Station in western Oregon, then became a UW professor in 1986 after 30 years as a forester. He was one of the first scientists to study natural forest ecosystems, particularly old-growth forests, and is often referred to as the “father of new forestry.”

“From my perspective, Jerry Franklin is one of the most influential forest ecologists of our time,” said , professor and director of the .

“Jerry has been instrumental in the evolution of forestry in the Pacific Northwest and continues to push the envelope on creating an ecological approach to forestry that appropriately integrates people into the larger forest ecosystem.”

Franklin worked for former President Bill Clinton on the controversial , the series of federal policies and guidelines that essentially reversed clear-cutting of old growth and refocused the Forest Service’s mission on nurturing forest ecosystems and their biological diversity. He also advised the U.S. House of Representatives and continues to work with the Obama administration on forest policy issues.

These tasks weren’t easy, and Franklin said he has angered both sides — environmentalists and timber companies — by advocating the best science for forest management.

“I’ve riled up everybody,” Franklin said with a laugh. “I’ve always viewed my clients as the trees and forests. I don’t pick up anybody’s agenda for them.”

Franklin has also served on a number of boards and governing panels, including The Wilderness Society, the Ecological Society of America and the Nature Conservancy. He has published more than 450 scientific articles and books.

“Jerry helped reveal the richness and complexity of forest biomes, adding immeasurably to our understanding of the world around us, and providing a new benchmark upon which future scientists will build,” said Will Price, acting president of the Pinchot Institute for Conservation.

“Through Jerry’s dedication to communicating scientific results and informing decision-makers, ecologically sound forest management techniques that were characterized as ‘new forestry’ a generation ago have now become conventional wisdom in the management of forests in the Pacific Northwest, across the country, and around the world. Jerry’s remarkable courage and commitment were critical in this achievement.”

Franklin’s previous honors include an from the Heinz Foundation and a in 2004 from the Society for Conservation Biology.

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For more information, contact Franklin at jff@uw.edu or 206-543-2138.