Silvia Purata and I made this video (in Spanish) for foresters in the Selva Maya (see Selva Maya III and Selva Maya Interrupted) to show them how to make dendrometer bands for measuring tree growth. The bands provide a very precise estimate of radial increment. When they are properly fitted, you can actually see the tree swell after a rain storm. [NOTE: The video was filmed in the Parque Zoológico of Chetumal in Quintana Roo and edited in a local hotel room using Final Cut Express and my Powerbook. Silvia did the voice-overs].