Science Diary: Redwoods – Ancient Productivity

music; ambience

SS: “Well, 2008 wasn’t such a good year for the economic situation, but we did learn an awful lot about trees this year.”

As humans age, our productivity typically wanes and our bodies wither. Not so for redwood trees. Welcome to Pulse of the Planet’s Science Diaries, a glimpse of the world of science from the inside. Steve Sillett is an ecologist at Humboldt State University. He is often found perched atop some of our largest trees, like this redwood in California.

SS: “I’m at the top of a really large redwood in Prairie Creek redwood state park. One of the biggest surprises this year for me was the realization that the rate at which a tree puts on wood each year is linearly related to its age in a positive direction. So in other words, for redwood, for up to 2000 years, on average, each year the tree is adding more wood than it did the year before. It’s puzzled me as to how the notion came about that trees slow down and begin to decline and become decadent after relatively short period of time relative to the life span. And I think the reason is because if you’re on the ground and stretching a tape around a tree, and measuring its diameter, from year to year there’s actually very little change in large trees, in fact in some cases because of irregularities in the bark and the precise location of the tape, you can actually see no change or even what appears to be a shrinkage. But the thing is, if you take that small ring of wood and you express that across the entire surface area of the tree’s woody body, you realize that the bigger the tree, the more surface area, and even a small annual increment can be a humungous amount of wood.”

Please visit our website at pulseplanet.com. Pulse of the Planet’s Science Diaries are made possible by the National Science Foundation. I’m Jim Metzner.

Science Diary: Redwoods - Ancient Productivity

Two-thousand years old and still growing! It appears that giant redwoods continue to grow, despite their extraordinary age.
Air Date:05/18/2009
Scientist:
Transcript:


music; ambience

SS: "Well, 2008 wasn't such a good year for the economic situation, but we did learn an awful lot about trees this year."

As humans age, our productivity typically wanes and our bodies wither. Not so for redwood trees. Welcome to Pulse of the Planet's Science Diaries, a glimpse of the world of science from the inside. Steve Sillett is an ecologist at Humboldt State University. He is often found perched atop some of our largest trees, like this redwood in California.

SS: “I'm at the top of a really large redwood in Prairie Creek redwood state park. One of the biggest surprises this year for me was the realization that the rate at which a tree puts on wood each year is linearly related to its age in a positive direction. So in other words, for redwood, for up to 2000 years, on average, each year the tree is adding more wood than it did the year before. It's puzzled me as to how the notion came about that trees slow down and begin to decline and become decadent after relatively short period of time relative to the life span. And I think the reason is because if you're on the ground and stretching a tape around a tree, and measuring its diameter, from year to year there's actually very little change in large trees, in fact in some cases because of irregularities in the bark and the precise location of the tape, you can actually see no change or even what appears to be a shrinkage. But the thing is, if you take that small ring of wood and you express that across the entire surface area of the tree's woody body, you realize that the bigger the tree, the more surface area, and even a small annual increment can be a humungous amount of wood.”

Please visit our website at pulseplanet.com. Pulse of the Planet’s Science Diaries are made possible by the National Science Foundation. I’m Jim Metzner.