Craning at the treetops
Washington's Wind River Experimental Forest will soon have an unusual inhabitant: a 90-metre-high steel-and-concrete monster. In a $1-million project, a giant crane will help scientists study life forms in the canopy of the old forest, which is part of the Gifford Pinchot National Forest (Science, Vol 264, No 5167).
Canopies, until recently unexplored, are proving to be a key to forest health and growth. Satellite pictures can at best provide a bird's-eye view of the woods and, on sharper focussing, a rough idea of arboreal diversity. However, to really fathom what's happening in the treetops, the researcher has to take up tree-climbing classes. But because not all of them can do a Tarzan, cranes are emerging as an alternative.
The crane will lower scientists in a gondola to any location in a 2-ha patch of forest. From the gondola, they can reach out to the uppermost branches to study lichens and fungi, which are nitrogen-fixers and food for a variety of organisms. They can measure volatile gases and the effect of pollution. Besides, scientists also hope to discover a host of new invertebrates.
The first forest canopy crane, erected in a park in Panama City 4 years ago, has already provided a wealth of new data on life in the tropical treetops. In the Amazon, a blimp was used to spread a net on treetops, on which scientists could walk and collect samples.