Canker

Canker was a type of fungus which caused disease in plants.

In 2269, during the battle between Spock and Spock One on Organia, Captain James T. Kirk (due to the effects of the thought-shield) saw a baobab-like tree quickly wilt and rot, as if it had been attacked simultaneously by mildew, black spot, canker, fireblight and Titanian mold.