Termites in Houston do not take winters off. The soil stays warm enough, the humidity stays high enough, and colonies keep working through every month of the year. Spring is just when they become visible — swarms of winged termites emerging around windows, doors, and light fixtures signal that a colony is mature and expanding. In the Lake Houston corridor, that signal deserves a quick response.
Dealing with this around your home?
If you have observed a termite swarm or found discarded wings near windows or doors in your Houston-area home, contact Rainbow Pest to schedule an inspection before another active foraging season passes.
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Why Houston Has Year-Round Termite Activity
Termite colonies stop foraging when soil temperatures drop — which in most of the country means winter gives the structure a break. Not here. Houston's average January soil temperature at six inches rarely falls below 50 degrees Fahrenheit. That is warm enough to keep colonies foraging all year. The damage clock does not pause in December.
Texas A&M AgriLife Extension designates the entire Houston metro, including the Lake Houston corridor and northeastern suburbs, as a moderate-to-high termite hazard zone. The combination of clay soils that retain moisture, high annual rainfall, and temperatures that support year-round foraging drives this elevated risk designation.
The Spring Swarm Calendar for the Houston Area
Termite swarms are triggered by a combination of temperature, humidity, and day length. In the Houston area, native Eastern subterranean termites typically swarm from late February through April, often in the morning hours following a warm rain. Swarms are brief — most last less than an hour — but the winged termites, called alates, are noticeable in large numbers near windows, light fixtures, or on the exterior of the structure.
Formosan subterranean termites swarm later in the season — typically from April through June, in the evening hours, often attracted to lights. Formosan swarms can involve dramatically larger numbers of individuals than native species swarms, and Formosan colonies are more destructive once established. Both species are present in the Northeast Houston area.
What a Swarm Actually Tells You
A swarm of winged termites inside your home is a significant indicator that a mature colony is active in or under the structure. Colonies do not produce alates until they are several years old and have reached a substantial size. Seeing a swarm indoors — as opposed to outdoors — means the source colony is almost certainly within the structure or in the soil immediately beneath it.
A swarm outdoors, on the other hand, could represent a colony in a tree stump, a neighboring property, or the soil in your yard rather than your home's framing. Outdoor swarms warrant inspection to determine whether the colony has access to structural wood, but they are not automatically evidence of an active infestation inside the building.
Distinguishing Termite Swarmers from Flying Ants
Termite swarmers and flying ants are frequently confused, and the distinction matters because they require different responses. Termite alates have straight antennae, two pairs of wings of equal length, and a straight waist with no constriction. Flying ants have elbowed antennae, two pairs of wings with the front pair noticeably larger than the rear, and a constricted, pinched waist.
Saving a few individuals in a sealed bag for professional identification is worth doing if you are uncertain. The response to a flying ant swarm is substantially different from the response to a termite swarm in a residence.
- Termite alate: straight antennae, equal-length wings, no waist constriction
- Flying ant: elbowed antennae, unequal wings, pinched waist
- Termite wings detach easily and are often found in piles near light sources
- Save specimens in a sealed bag for professional identification if uncertain
Acting on a Swarm: Timeline Matters
After a swarm, the winged termites that do not establish new colonies die quickly — they are not the damaging element of the colony and do not feed on wood. The urgency is not the swarmers themselves but what they indicate: a mature colony that is active in or around your structure, which has likely been causing damage for years before producing its first swarm.
Scheduling a professional inspection within a few weeks of observing a swarm allows identification of the active colony's location, assessment of any existing damage, and selection of an appropriate treatment method before the next season's foraging peak. Delaying inspection after a swarm observation means the colony continues to cause damage through another active season.