Herbivory and a Simple Field Test for Total Phenolics in Trees

Herbivory and a Simple Field Test for Total Phenolics in Trees 

Some northern trees and phenolics reactions with ferric chloride. The phenolics stains are shown on cross sections of twigs in the middle two rows 

Mtiller-Schwarze, Hands-On Chemical Ecology Simple Field and Laboratory Exercises 75 

Many deciduous and coniferous trees contain varying levels of phenolics, including tannins. Blackwater rivers in forested areas of the world, such as the Amazon basin or the southern United States, carry phenolics (tannins) leached out of trees. Such rivers differ in plant and animal life from whitewater rivers.  

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