Ticks in St. Louis

Ticks of the St. Louis Area

Ticks aren’t insects — they’re arachnids, closer cousins to mites and spiders. Each hatches as a tiny six-legged “seed tick,” then needs a blood meal to molt into an eight-legged nymph and again into an adult. They can’t jump or fly; instead they “quest” — climbing to the tips of grass and low brush, usually only ankle-to-knee height, and grabbing on as a warm body brushes past. They can survive months between meals, and any tick should be treated as a possible disease carrier. In a yard they concentrate right where the lawn meets the trees, brush and tall grass — which is exactly the harborage zone we target, along with keeping grass short and clearing leaf litter. (Pets need their own vet-provided tick protection, too.)

Lone Star Tick

Amblyomma americanum

Identify: Reddish-brown and rounded; the adult female carries a single cream-white dot in the center of her back — the “lone star” that names her.

Habitat & behavior: The aggressive human-biter of Missouri woods, trails and yard edges — all three stages will bite people, and it’s the tick you’re most likely to pull off in this area.

Why it matters: A vector of ehrlichiosis, and increasingly linked to the alpha-gal red-meat allergy. (This species isn’t detailed in our reference text; these facts are from current tick references.)

American Dog Tick

Dermacentor variabilis

Identify: Brown, mottled with silvery-white markings; swells to slate-gray when engorged. Noticeably larger than a deer tick.

Habitat & behavior: Adults prefer dogs but bite many large animals; the young stages feed on small rodents. The most common Dermacentor across the eastern and central U.S.

Why it matters: The main carrier of Rocky Mountain spotted fever, and one of the ticks that can cause tick paralysis.

Blacklegged / Deer Tick

Ixodes scapularis

Identify: Small and dark-legged — much tinier than the dog tick, so it’s easy to miss until it’s attached.

Habitat & behavior: Feeds on white-tailed deer and mice, and is densest right along the wooded edge of a yard. The nymph is the stage most likely to bite people.

Why it matters: The principal carrier of Lyme disease. Because the biting nymph is the size of a poppy seed, prompt tick checks after time outdoors matter.

Tick biology and yard-control principles per Truman’s Scientific Guide to Pest Management Operations, Ch. 12. Lone star tick specifics are from current tick references, as that species is not detailed in this edition.