Year Model years requiring a test. 2014 1990, 1992, 1994, 1997, 1999, 2001, 2003, 2005, 2007. 2015 1991, 1993, 1995, 1996, 1998, 2000, 2002, 2004, 2006, 2008. 2016 1992, 1994, 1997, 1999, 2001, 2003, 2005, 2007.
An important pest of livestock and horses throughout the western United States. In California, this tick is frequently found in the warm, dry regions of the central valley down to the southern portion of the state. Rarely, these ticks have been found on humans, dogs, cats, and sheep.
Brown Dog Ticks have a world-wide distribution, and can be found throughout the United States, although they are encountered more frequently in the southern tier of states. All life stages of this tick can transmit Rocky Mountain Spotted Fever rickettsia (Rickettsia rickettsia) to dogs, and rarely to humans.