Ticks in South Dakota
Ticks are active in South Dakota whenever the ground is not frozen, led by the Lyme-carrying deer tick. TickZone scores all 310 South Dakota towns every morning, so risk stays local: pick your town for today's number, a 7-day outlook, and what's driving it.
Tick season in South Dakota
Tick season in South Dakota runs whenever the ground is not frozen, roughly March through November, with two peaks. Nymph deer ticks, the poppy-seed-sized stage that causes most Lyme cases, peak from late May through July. Adult deer ticks make a second push in October and November, and on any winter day above about 40 F they can quest again. American dog ticks are busiest from April through July.
| Life stage | J | F | M | A | M | J | J | A | S | O | N | D |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Deer tick nymphs | ||||||||||||
| Deer tick adults | ||||||||||||
| American dog tick |
Those are averages, and any single week can run hotter or colder than the calendar suggests. The daily score on every town page folds the season, the weather, and local habitat into one number each morning, so it is the safer way to time yard work, hikes, and pet prevention.
Highest-risk towns in South Dakota (2026)
South Dakota's highest-risk towns are spread across several counties, led by Lawrence. The top 10 towns run 0 to 89 percent forest, ranked at peak season so the list stays stable.
- 1Wetonka McPherson CountyModerate at peak
- 2Keystone Pennington CountyModerate at peak
- 3Central City Lawrence CountyModerate at peak
- 4Deadwood Lawrence CountyModerate at peak
- 5Brant Lake Lake CountyModerate at peak
- 6Lead Lawrence CountyModerate at peak
- 7Strandburg Grant CountyModerate at peak
- 8Astoria Deuel CountyLow at peak
- 9Hill City Pennington CountyLow at peak
- 10Fairview Lincoln CountyLow at peak
All South Dakota towns, by county
Aurora County · 3 towns
Beadle County · 8 towns
Bennett County · 1 towns
Bon Homme County · 5 towns
Brookings County · 8 towns
Brown County · 10 towns
Brule County · 3 towns
Butte County · 4 towns
Campbell County · 4 towns
Charles Mix County · 7 towns
Clark County · 7 towns
Clay County · 2 towns
Codington County · 6 towns
Corson County · 3 towns
Custer County · 5 towns
Davison County · 3 towns
Day County · 8 towns
Deuel County · 7 towns
Dewey County · 3 towns
Douglas County · 3 towns
Edmunds County · 4 towns
Fall River County · 3 towns
Faulk County · 7 towns
Grant County · 9 towns
Gregory County · 6 towns
Haakon County · 2 towns
Hamlin County · 6 towns
Hand County · 3 towns
Hanson County · 4 towns
Harding County · 2 towns
Hughes County · 3 towns
Hutchinson County · 6 towns
Hyde County · 1 towns
Jackson County · 4 towns
Jerauld County · 3 towns
Jones County · 2 towns
Kingsbury County · 9 towns
Lake County · 5 towns
Lawrence County · 5 towns
Lincoln County · 7 towns
Lyman County · 4 towns
Marshall County · 5 towns
McCook County · 5 towns
McPherson County · 5 towns
Meade County · 4 towns
Mellette County · 2 towns
Miner County · 4 towns
Minnehaha County · 11 towns
Moody County · 5 towns
Oglala Lakota County · 1 towns
Pennington County · 8 towns
Perkins County · 2 towns
Potter County · 4 towns
Roberts County · 10 towns
Sanborn County · 3 towns
Spink County · 10 towns
Stanley County · 1 towns
Sully County · 2 towns
Todd County · 2 towns
Tripp County · 3 towns
Turner County · 10 towns
Union County · 5 towns
Walworth County · 6 towns
Yankton County · 6 towns
Ziebach County · 1 towns
South Dakota tick questions
- Are there ticks in South Dakota?
- Yes. South Dakota has ticks in every county, led by the deer tick (blacklegged tick) that spreads Lyme disease, along with the American dog tick. They are active whenever the ground is not frozen, and today 6 of the state's 310 towns are at moderate or high tick risk on TickZone's daily score.
- What types of ticks live in South Dakota?
- South Dakota has the deer tick (blacklegged tick), which carries Lyme disease; the American dog tick; and the lone star tick, which is not established in the state and causes alpha-gal syndrome. See the South Dakota tick identification chart for photos and how to tell them apart.
- When does tick season start and end in South Dakota?
- In South Dakota, ticks are active whenever the ground is not frozen, roughly March through November. Nymph deer ticks peak in June and July and cause most Lyme cases, and adult ticks have a second peak in the fall. On any winter day above freezing, adult ticks can still bite.
- When is flea and tick season?
- Flea and tick season generally runs from early spring through late fall, peaking in the warm summer months. In South Dakota, start prevention for pets and people in March and keep it up through November, since ticks can bite on any mild day.
- Which tick carries Lyme disease in South Dakota?
- The deer tick, also called the blacklegged tick, is the tick that spreads Lyme disease in South Dakota. The American dog tick and lone star tick do not carry Lyme.