While there are many kinds of ticks that are present throughout the United States, only a few types of them are regular pests for people and pets. Your geographic location dictates the kinds of ticks that you may encounter, as well as the local ecology, the season, and your activities.
There are some ticks that stay for most of their lives on a single animal, and others that hide within or near the nests or burrows of their hosts when they’re not actively blood feeding. Most of us would rarely encounter these ticks, but sometimes their animal hosts bring the ticks into the home. For example, if there are bats that roost in an attic or chimney, they may bring bat ticks into living spaces. Also, rodents and birds may bring their own kinds of ticks into homes and cabins. Most commonly, these ticks wander into the human living spaces if their normal hosts have died or abandoned that roost or nesting site.
Other kinds of ticks are active outdoors in areas of high grass, brush, around woodpiles, in forested areas, in deserts, and around beaches. A brown dog tick can thrive and complete its entire life cycle inside a home, though this may not be its preferred environment.
When the temperatures are above freezing is when ticks are most active. Some ticks seek hosts in the cooler and more humid hours around dawn and dusk, but others are most active during the hot and dry midday conditions.