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families are quite different. Hard ticks are commonly found in wooded or weedy areas containing a good number of hosts such as deer, cattle, dogs and small mammals. 
• "Soft ticks, encountered infrequently by human, are generally found in animal burrows or dens, dilapidated human dwellings and animal shelters. Many soft ticks are parasites on birds and bats," Hadi said.
• He says two of the most critical species of hard ticks found outdoors in South Dakota are the American dog tick or Dermacentor variabilis and the Rocky mountain wood tick or Dermacentor andersoni. 
• While American dog ticks are probably widely distributed across the state, the presence of Rocky mountain wood tick is more limited to the western side of the state.
• American dog ticks are reddish brown in color. The adult unfed females measured to about 0.18 inch long, slightly larger than adult males which measure about 0.14 inch long. When engorged, female American dog ticks measure about 0.59 inch long. Both female and male American dog ticks have a marbled or silvery dorsal shield on their back. The females' shields are relatively short and do not cover the whole body while the males' shield cover the whole length of their bodies.
• The immature American dog ticks feed on small mammals and are active in winter and spring. The adults are abundant in late spring and early summer and feed on dogs and bigger mammals including humans.
• Rocky mountain wood ticks are dark brown in color with a silver-grey dorsal shield. Like the American dog tick, the female ticks have a short dorsal shield while the male ticks' shields extend over the length of the body. The size of unfed female and male Rocky mountain wood tick are roughly similar, about 0.2 inches long. Engorged female Rocky mountain wood ticks can measure about 0.64 inches long.
• Immature Rocky mountain wood ticks are most abundant in summer, feeding on small mammals. In fact, the primary reports of Rocky mountain wood ticks in South Dakota came from the burrows of black-tailed prairie dogs in the western half of the state (Kietzman 1987). The nymph and adult ticks are active in late spring and early summer and they feed on medium- and large-sized mammals.
• Representation of tick-borne diseases associated with two common hard ticks in South Dakota
• Tick species- Human diseases
• American dog tick- Tularemia, Rocky Mountain spotted fever, Powassan encephalitis
• Rocky mountain wood tick- Tularemia, Rocky Mountain spotted fever, Colorado

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