Killing trees in the name of science

Scientists do not fully understand how trees die. Why do some live and others die? How long does the process take? What is the impact of stress? Nate McDowell is one of the scientists at the Los Alamos National Laboratory trying to find answers.

NPR paid a visit to the research facility last year:

Nate McDowell runs what you might call a "tree torture" lab. It's actually outside in the desert, near the national lab. He's growing a group of pinon and juniper trees, about 15 feet high. Plastic gutters keep rain away from the tree roots, to simulate drought. The trees themselves are growing inside clear plastic chambers -- tubes with no tops. Silvery hoses carry heated air into the chambers.

We climb in through a hole in the chamber where you can immediately feel the heat. It's about 7 degrees hotter than the outside, roughly the increase predicted by computer models of climate change over the next 80 years or so.

McDowell is simulating drought and a warmer climate. He measures how the trees respond -- there are instruments stuck into and all over the trees. Even wrapped around the stem. "Every few minutes they measure the diameter of that tree," he explains. The trees look like patients in intensive care -- wired up with tubes coming out of the stems. All to see what it takes to kill it. "Everyone knows it gets hot and dry; you know, beetles show up, the trees are dead," McDowell says, "but we don't really understand it."

McDowell joins The Daily Circuit Jan. 8, 2013 to discuss his research.