epiphytotic

adjective

ep·​i·​phy·​tot·​ic ˌe-pə-ˌfī-ˈtä-tik 

: of, relating to, or being a plant disease that tends to recur sporadically and to affect large numbers of susceptible plants

epiphytotic noun

Word History

Etymology

epi- + -phyte + -otic (in epizootic)

First Known Use

circa 1899, in the meaning defined above