Chelsea Byrd now works in biodefense, but has maintained close ties with her OSU mentor, Dennis Hruby, throughout the years. He continues to be a role model. (photo: Jim Folts)

As an undergrad, Byrd was persistent in looking for research opportunities, and while she heard Hruby had a tough reputation, she wanted “someone who could push me,” she says.

And he would. As with all students, Hruby laid out his high expectations as well as the demands of biomedical science. Still, Byrd had the enthusiasm and motivation Hruby looks for. When asked what she wanted to be, Byrd responded, “I want to be you. And I’m not leaving until you say yes.”

Hruby has built mentoring into the structure of his research labs. Any incoming student or employee works with someone more experienced, who works with a more senior scientist, who reports to Hruby. That gives the new person the advantage of working with somebody familiar with the day-to-day science, Hruby says. And at each step up the hierarchy, the scientists get the experience of mentoring the people working under them.

Like most mentors, Hruby gains satisfaction from seeing students like Byrd grow and succeed in their chosen careers. He also knows the value of having a mentor from his own experience; he had them as an undergrad, but not in graduate school and wishes he had.

“Anybody in complex science and academia shouldn’t have to learn everything from scratch,” Hruby says. “It’s good to have someone older guide you in the right direction.”

As a mentor, Hruby tells his incoming graduate students his role is to be a resource, providing a laboratory, funding, a great project and fine-tuning. “They’ll have to do everything else,” he says. “That’s the skill set they need to learn to be successful.”

Which Chelsea Byrd has done and is.

~ Gary Dulude

Reporters from National Geographic, Scientific American, The Associated Press and others learned about OSU's marine-related expertise.

For three days in August, influential news media representatives from around the country got a taste of what makes OSU one of the nation’s top marine research universities.

As part of “Our Changing Coastal Ocean: A News Media Fellowship Program,” journalists toured labs and heard presentations in Corvallis and at Hatfield Marine Science Center in Newport on topics ranging from coastal ecology and salmon hatcheries to the ocean observing initiative.

Participants represented National Geographic, Scientific American, The Seattle Times, The Oregonian, Environmental Science and Technology, National Public Radio’s Pacific Northwest affiliates, the Associated Press and Oregon Public Broadcasting. The head of media relations for the National Science Foundation (NSF) also joined the program. The goal was to familiarize reporters with OSU’s expertise in issues related to climate change, marine mammals, commercial fisheries, ocean productivity and marine observing technologies.

“OSU’s marine researchers are leaders in their fields,” said Luanne Lawrence, vice president for University Advancement, which created and funded the program. “We help to develop ocean policies at the international and national levels and lead state and regional organizations. We wanted reporters who cover marine topics to meet our scientists in person and hear about their latest work.”

The program focused on the coastal ocean. Reporters learned about ongoing research on the seasonal “dead zone,” on marine mammal migrations and on wave energy developments. At OSU’s NSF-funded ocean sediment core repository, they heard how evidence in ocean sediment cores is shedding light on the frequency and severity of subduction zone earthquakes, such as the one that devastated countries around the Indian Ocean in 2004. At the O.H. Hinsdale Wave Research Lab, the group visited the tsunami wave basin and heard about plans to build a facility to study hurricane-generated waves.

In addition to lab visits, reporters met informally with OSU scientists at the HMSC and with community representatives at the Oregon Coast Aquarium. The impact of science on decision-making was the focus of discussions with state Sen. Betsy Johnson of Scappoose, state Rep. Jean Cowan of Newport and with people from local government and the fishing, economic development and tourism industries.

OSU is home to the third-largest assembly of marine researchers in the nation. They are based in the colleges of Oceanic and Atmospheric Sciences, Agricultural Sciences and Science as well as the Coastal Oregon Marine Experiment Station, Oregon Sea Grant, the Marine Mammal Institute, the Hatfield Marine Sciences Center and the OSU Seafood Research Laboratory in Astoria.

Just a few days later, select OSU Agricultural Sciences and Extension and Experiment Station faculty had a similar opportunity to get up close and personal with key media during a fellowship produced by the Institute for Journalism and Natural Resources. Since 1995, IJNR has sought to foster higher standards of news coverage of natural resources and the environment, and its “Willamette Valley Institute” brought journalists together for one week to hear from experts and tour key areas.

At OSU, they heard from a panel of faculty on the topic of genetic modification of crop plants and from individual researchers on organic agriculture. Participating reporters represented such outlets as the Associated Press, the Washington Post and Jefferson Public Radio.

~ by Nick Houtman

David Woodruff, USDA Forest Service researcher, climbs tall Douglas-fir trees to determine what controls their maximum height.

The Douglas-fir, state tree of Oregon, towering king of old-growth forests and one of the tallest tree species on Earth, finally stops growing taller because it just can’t pull water any higher, a new study concludes.

This limit on height is somewhere above 350 feet, or taller than a 35-story building, and is a physiological tradeoff between two factors in the tree’s wood – a balance between efficiency and safety in transporting water to the uppermost leaves.

The findings are being published this week in Proceedings of the National Academy of Sciences, by a team of scientists from Oregon State University and the U.S.D.A. Forest Service. The research was funded by grants from the U.S. Department of Agriculture and the Forest Service.

“People have always been fascinated by how some trees, such as Douglas-fir or redwoods, can grow so tall,” said Barb Lachenbruch, a professor of wood science at Oregon State University. “This is not an easy thing to do. Think about trying to drink water through a narrow, 350-foot-long straw. It takes a lot of suction.”

Douglas-fir wood consists mostly of dead cells called “tracheids” that function in water transport and physical support, the researchers said. These tracheids have pits on their sides that function as valves, allowing water to go from one tracheid to the next, and the pits have a membrane with an impermeable middle. Normally, water flows through the porous edges of the membrane, but if there’s an air bubble in one tracheid, the membrane moves to the side and blocks off the pit so air bubbles can’t spread.

Although it’s important to allow water to pass efficiently from one wood cell to the next, air bubbles would block water movement altogether. Because water is pulled through a tree by the forces of evaporation from the leaf surfaces, the water is in “tension,” like a pulled rubber band. If an air bubble gets in, it’s like the rubber band breaking and water can no longer be transported. With a 350-foot-long water column, there’s a lot of tension on the water in the cells at the top of the tree, and a lot of force trying to get errant air bubbles to enter.

“Higher and higher in the tree, the valves change so they are able to withstand more pulling force from the long, heavy column of water before air bubbles can be sucked through,” Lachenbruch said. “But the problem is that the valves become less efficient at letting water pass. The height at which no water would pass at all, according to our models, coincides with the tallest records for Douglas-fir, about 350 to 400 feet.”

Trees of that height were discovered in Washington and British Columbia in the late 19th and early 20th centuries. The tallest Douglas-fir today is a 326-foot-tall tree in Oregon’s Coos County.

“As you go higher and higher in a Douglas-fir tree, it’s almost like experiencing a drought,” said Rick Meinzer, a Forest Service scientist at the Pacific Northwest Research Station. “And that’s what we see at the tops of very tall trees. The foliage is struggling to get enough water and seems to be under drought stress. It’s not unusual to see periodic die-back at the tops of very tall Douglas-fir trees that are near their height limits.”

At a specific height determined by the physical structure of these pits and their membranes, the scientists discovered, the fierce resistance put up by the Douglas-fir to prevent any spread of air bubbles also prevents water from being pulled any higher. That is where it finally stops growing in height, no matter how favorable any other conditions might be, such as climate, soil or water availability.

The studies, Meinzer said, may improve our understanding of how trees grow in height and may be able to adapt to different environments, including their ability to deal with droughts or climate change.

Although height can be important in a competition for sunlight and photosynthesis, natural selection has not favored a wood structure in Douglas-fir that facilitates water transport at even greater tensions and allows for greater height, the scientists noted in their study.

Apparently 350 feet is tall enough.