The feeding activity of female black flies may cause considerable annoyance to saddle horses. Horses under attack become head-shy and difficult to manage, posing a potential hazard to riders. Stabling horses offers a means of protection against black fly feeding, but most horse owners cannot or will not stable their animals to prevent disturbance by noxious flies. Because stabling is an unsatisfactory control measure, I will evaluate various ear protectants to find easily applied materials of suitable effectiveness and duration on pastured animals to be of practical value to the owners. / Master of Science