Yaupon psyllid (Gyropsylla ilecis) galls were recently noticed on yaupon hollies (Ilex vomitoria), including the cultivar 'Will Fleming,' at the Craven County Agricultural Building. Currently, yaupon holly is the only known host of the yaupon psyllid. According to the University of Florida's information note on this topic, "The yaupon psyllid is considered a minor aesthetic pest due to the unsightly presence of galls and some stunting of twigs. However, yaupon holly is rarely severely damaged by this insect." Insecticide sprays are not recommended for this problem, but if only a few galled/damaged leaves are noted, you might consider removing these to reduce the population for next year.
Perhaps the most important things to know about the yaupon psyllid are as follows: 1) the galls do not result from a disease, so forget about fungicide sprays; and 2) your yaupon holly will not die as a result of this particular problem.
