Ball Mountain is an isolated, mostly heavily forested peak reaching the subalpine zone (2,330 m) in eastern Siskiyou County north of Mt. Shasta, California. It supports a rich fauna of at least 68 butterfly species showing affinities to the faunas of the Trinity Alps and Eddies, the Warners, and the Cascades. Rare or endemic entities include Speyeria monnonia, Lycaena heteronea gravenotata, and melanic forms of Speyeria atlantis and Agriades "glandon."Several zones of intergradation or hybridization impinge on the fauna as well.
Shapiro, Arthur M.
"Montane insular butterfly biogeography: fauna of Ball Mountain, Siskiyou County, California,"
Great Basin Naturalist: Vol. 46
, Article 28.
Available at: http://scholarsarchive.byu.edu/gbn/vol46/iss2/28