| ELISA | a test in which an antibody carries an enzyme that releases a colored compound, signifying the presence of the pathogen. |
| endophyte | an organism that grows within a plant. |
| eradicate | to do away with completely. |
| eriophyid | a family of tiny plant feeding mites that possess only 4 legs; they are highly host specific (feeding on only one species) and their damage is predictable and often dramatic. |
| evergreen | having green foliage throughout the year. |
| excrement | the waste products eliminated by an insect, principally from digestion; feces. |
| excreta | the waste products eliminated by an insect, principally from digestion; feces. |