Redwoods now part of wireless network
UC Berkeley scientists create unusual weather stations
By Marsha Walton
(CNN) -- When biology professor Todd Dawson says "climb," his students ask, "how high?"
Shimmying up an enormous redwood tree is not a typical assignment for graduate students.
But it's part of the workload for some of Dawson's graduate students at the University of California at Berkeley.
The researchers are installing miniature weather monitoring stations -- only about the size of 35mm film canisters -- in the trees.
Inside that small package: sensors that measure light, temperature, humidity, and barometric pressure. Another layer is a sort of micro-sized PC to process and store that data, a low power radio and a small battery to transmit the readings. It's designed to function for about three months. There's also the option of a small solar power source, which could keep the monitor functioning indefinitely.
"The sensors are constantly collecting information," said Dawson. "We can program the software to average every five minutes, or every half hour of data," he said.
David Culler, a professor of computer science, and UC Berkeley graduate students developed the sensor boards and networking software for the devices.
Earlier equipment to do that same job was bulky and weighed about 30 pounds, and it had to be attached to thousands of feet of cable that was much more intrusive to the forest.
Observing the 'fog belt'
The redwood research looks at how the trees absorb moisture from fog. The natural range of these majestic trees is limited to a "fog belt." There are different weather patterns because of the trees, says Dawson.
"One thing lacking in the forestry community is precise environmental information," said Dawson. "These sensors will help predict how trees are going to grow under a variety of circumstances."
Scientists expect to use sensors in the future to develop healthier and more sustainable forests, and to assist firefighting crews in determining where the highest risk areas are while fighting wildfires. Wildfire meteorologists already measure moisture content of soil and trees near fires. If they are used in a widespread way, additional sensors could help in fighting wildfires.
About 50 sensors on five redwood trees at the university's botanical gardens are part of the project's first phase. Additional research is likely in state and national parks where redwoods are accessible and protected. Later this year the wireless network will include redwood groves in Big Basin Redwoods State Park in Santa Cruz County and in Sonoma County.
Dawson says other forest biologists are interested in using the technology in the eucalyptus forests of Australia. Eventually the devices could be used in precision agriculture, vineyards, even home gardens.