Determining When Trees Are Drought Stressed

By Richard Waring / On February 18th, 2019
Unlike most annual crops, the roots of long-lived trees can penetrate through soils to great depth to reach water (Figure 1).  If we can’t tell how deeply roots penetrate, how do we determine when trees run out of water?  One way is to monitor the moisture status of leaves and twigs, because these are connected through the sapwood in branches, stems, and roots to water deep underground.
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Creating Resilience: Trophic Cascades and Climate Change

By Cristina Eisenberg / On August 23rd, 2011
Ecologist Robert Paine summed up the effects of keystone predator removal by saying, “You can change the nature of the world pretty simply. All you need to do is remove one species.” In The Wolf’s Tooth, I compare ecosystems from which carnivores have been removed to a game of Jenga. This game involves removing wooden blocks one at a time from a tower without causing it to collapse. As you remove them, the tower starts to teeter, loosening some of the blocks, making them easier to remove.