Ticks in Iowa
Ticks are active in Iowa whenever the ground is not frozen, led by the Lyme-carrying deer tick. TickZone scores all 940 Iowa 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 Iowa
Tick season in Iowa 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 | ||||||||||||
| Lone star 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 Iowa (2026)
Iowa's highest-risk towns are spread across several counties, led by Clayton. The top 10 towns run 60 to 97 percent forest, ranked at peak season so the list stays stable.
- 1Westwood Henry CountyModerate at peak
- 2Keomah Village Mahaska CountyModerate at peak
- 3University Heights Johnson CountyModerate at peak
- 4McGregor Clayton CountyModerate at peak
- 5Fraser Boone CountyModerate at peak
- 6Panorama Park Scott CountyModerate at peak
- 7Clayton Clayton CountyModerate at peak
- 8Sageville Dubuque CountyModerate at peak
- 9North Buena Vista Clayton CountyModerate at peak
- 10Windsor Heights Polk CountyModerate at peak
All Iowa towns, by county
Adair County · 5 towns
Adams County · 4 towns
Allamakee County · 6 towns
Appanoose County · 11 towns
Audubon County · 5 towns
Benton County · 14 towns
Black Hawk County · 9 towns
Boone County · 9 towns
Bremer County · 8 towns
Buchanan County · 11 towns
Buena Vista County · 10 towns
Butler County · 10 towns
Calhoun County · 11 towns
Carroll County · 13 towns
Cass County · 8 towns
Cedar County · 8 towns
Cerro Gordo County · 10 towns
Cherokee County · 8 towns
Chickasaw County · 8 towns
Clarke County · 3 towns
Clay County · 10 towns
Clayton County · 16 towns
Clinton County · 14 towns
Crawford County · 13 towns
Dallas County · 14 towns · 8/100k Lyme
Davis County · 4 towns
Decatur County · 10 towns
Delaware County · 11 towns · 28/100k Lyme
Des Moines County · 5 towns
Dickinson County · 10 towns
Dubuque County · 21 towns · 22/100k Lyme
Emmet County · 6 towns
Fayette County · 13 towns
Floyd County · 7 towns
Franklin County · 8 towns
Fremont County · 8 towns
Greene County · 7 towns
Grundy County · 9 towns
Guthrie County · 9 towns
Hamilton County · 9 towns
Hancock County · 8 towns
Hardin County · 12 towns
Harrison County · 10 towns
Henry County · 9 towns
Howard County · 5 towns
Humboldt County · 11 towns
Ida County · 5 towns
Iowa County · 7 towns · 49/100k Lyme
Jackson County · 12 towns
Jasper County · 13 towns
Jefferson County · 7 towns
Johnson County · 11 towns · 21/100k Lyme
Jones County · 8 towns
Keokuk County · 16 towns
Kossuth County · 12 towns
Lee County · 8 towns
Linn County · 17 towns · 11/100k Lyme
Louisa County · 9 towns
Lucas County · 5 towns
Lyon County · 8 towns
Madison County · 8 towns
Mahaska County · 9 towns
Marion County · 9 towns
Marshall County · 13 towns
Mills County · 7 towns
Mitchell County · 8 towns
Monona County · 10 towns
Monroe County · 3 towns
Montgomery County · 6 towns
Muscatine County · 8 towns
O'Brien County · 8 towns
Osceola County · 5 towns
Page County · 10 towns
Palo Alto County · 9 towns
Plymouth County · 11 towns
Pocahontas County · 8 towns
Polk County · 17 towns · 3/100k Lyme
Pottawattamie County · 14 towns
Poweshiek County · 8 towns
Ringgold County · 9 towns
Sac County · 9 towns
Scott County · 16 towns · 5/100k Lyme
Shelby County · 11 towns
Sioux County · 13 towns
Story County · 14 towns · 5/100k Lyme
Tama County · 12 towns
Taylor County · 8 towns
Union County · 7 towns
Van Buren County · 7 towns
Wapello County · 7 towns
Warren County · 13 towns
Washington County · 9 towns
Wayne County · 8 towns
Webster County · 13 towns
Winnebago County · 7 towns
Winneshiek County · 8 towns
Woodbury County · 15 towns
Worth County · 7 towns
Wright County · 8 towns
Iowa tick questions
- Are there ticks in Iowa?
- Yes. Iowa has ticks in every county, led by the deer tick (blacklegged tick) that spreads Lyme disease, along with the American dog tick and the lone star tick. They are active whenever the ground is not frozen, and today 131 of the state's 940 towns are at moderate or high tick risk on TickZone's daily score.
- What types of ticks live in Iowa?
- Iowa has the deer tick (blacklegged tick), which carries Lyme disease; the American dog tick; and the lone star tick, which is reported in the state and causes alpha-gal syndrome. See the Iowa tick identification chart for photos and how to tell them apart.
- When does tick season start and end in Iowa?
- In Iowa, 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 Iowa, 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 Iowa?
- The deer tick, also called the blacklegged tick, is the tick that spreads Lyme disease in Iowa. The American dog tick and lone star tick do not carry Lyme.