The objective of this research is to determine whether varying levels of acid rain contribute to the development or worsening of skin conditions in school horses. In this project I will compare the acidity of precipitation with the growth and pH tolerance of Dermatophilus congolensis (rain rot) from our horse's skin. Rain rot, also known as rain scald or dermatophilosis, is a skin infection caused by a bacterium known as Dermatophilus congolensis. Rain rot is often found on the horse's topline, but it can also be found on numerous areas of the horse's body including their hind end, face, and legs after a humid or rainy day. Rain rot can be identified by crusty scabs, matted hair, hair loss, and bumps on the skin, most commonly on the back, hind end, and neck. The affected areas may be sensitive to the touch and appear red or irritated underneath the scabs. Living on the horse's skin, D. congolensis is mostly dormant but under wet conditions this bacterium can cause an inflammatory infection resulting in lesions along your horse's skin. These lesions cause small patches of raised bumps which are scabs containing clusters of your horse's hair. Removal of these scabs results in bald patches along the affected area. In severe cases the lesions and scabs may become large and affect multiple layers of skin. When this occurs the horse's use may be impacted until the infection clears.