Tick Activity Periods

You may think ticks are only active in the spring and summer, but ticks are active in all four seasons. The black legged tick, Ixodes scalpularis, is a good example with activity that affects humans year round

Spring Nymphal ticks appear in May with peak activity May - July
Summer Nymphal ticks are active and larval ticks emerge in August with peak activity in August and September.
Fall Adult ticks emerge in October with peak activity in October and November.
Winter Adult ticks are active when the weather warms above freezing.


Diseases Ticks May Carry

Ticks carry many diseases that are harmful to humans. Nymphs and adults can feed on humans for five days or more, but the transmission of a tick-borne disease may occur much faster. Some of the diseases ticks carry include:

  • Lyme disease
  • Rocky Mountain spotted fever
  • Tularemia
  • Ehrlichiosis
  • Relapsing fever
  • Colorado tick fever
  • Babesiosis


Lifecycle of a Tick

Ticks go through four stages of life: egg, larva, nymph, and adult. Eggs are typically laid in the spring and hatch in the summer, making these seasons the critical times for tick control.

During the larva stage, ticks feed on small animals like rodents for several days before falling back to the ground and molting into nymphs.

Nymphs typically become active in the spring when they begin looking for a new meal. They feed most often on the white-footed mouse but can also feed on pets and humans. The risk of humans being bitten is greatest during the late spring and summer as nymphs mature into adults.

Once ticks become adults, they mate and can lay up to 3,000 eggs at once.


Do ticks die after the first frost?
No such luck! Some species, like American dog tick and Lone Star tick are just not active in fall and winter months. Others, like Blacklegged (deer) tick can remain active in their adult stage from fall to spring as long as the temperature is above freezing. Each life stage (larvae, nymph and adult) of any species of tick has a discrete time period when it is most likely to be looking for a host.

It's October and I'm seeing a lot of ticks in my yard. Why?
Blacklegged ticks are seasonal pests. The adult stages of this tick begin to become active as the season changes from summer to fall. In the northeastern U.S., these adult stage ticks start to become abundant early in October, and they will remain active through the winter as long as the temperatures are above freezing and the ground is not frozen or covered by snow.