Pest pressure in Snellville runs through most of the year rather than in one season. Native termite swarms appear in February and March, mosquitoes are active from spring into the fall, and late summer brings the reported peak for the southern house mosquito. Rodents tend to move indoors as nights cool, while ants and roaches carry on through a mild winter.
Key takeaways
- According to UGA, native subterranean termites begin swarming in February or March and swarm during the day.
- UGA advises walking a yard twice a week in summer, because Asian tiger mosquito adults can emerge in about three days.
- Regional news reports describe the southern house mosquito as breeding in storm drains, with a peak from August into mid-September.
- UGA lists the house mouse, Norway rat and roof rat as living in Georgia, and rodents usually come out at night.
- The Formosan termite swarms at night in late May or early June, but UGA says it is rare in Georgia.
- A last spring freeze in north Georgia cities usually falls between March 30 and April 10, which is a rough reference point for the season.
Why does pest pressure run all year in Snellville?
Snellville has a humid Southeast climate with a mild winter, so insects and rodents do not reliably stop in one season. The calendar is built around that pattern rather than a single peak.
The area's climate is humid for most of the year. A third-party weather summary gives an annual precipitation figure of roughly 50 inches, a January average around 41 F and a July average near 79 F. Those are hedged approximations rather than official normals, so read them as a general picture and not a table of record values. A homeowner who reads these numbers as a rough guide, and not as a promise, will get the most out of the calendar.
The last spring freeze in north Georgia cities, Atlanta among them, usually falls between March 30 and April 10, according to a Georgia public broadcaster's reporting. That gives a rough reference point for when outdoor pests start up in earnest. A mild winter means ants, roaches and spiders tend to carry on indoors, so the year does not have a clean end point for pest work.
What happens in January and February?
Rodents are still indoors from the autumn, termite inspections are often booked ahead of swarm season, and moisture under crawl-space houses can follow winter rain. February is when native termite swarms begin.
January is when rodents that moved in as nights cooled are still inside. Crawl-space houses can hold moisture after winter rain, so a technician may look under the house at this time of year. Termite inspections are often booked ahead of swarm season, because a homeowner who wants a clear picture before spring has the most time to act on what is found. A technician who visits in January will usually look at the entry points on the perimeter first, since the openings made in the cooler months are the ones that matter for the rest of the year.
February and March are the start of the termite swarms. The University of Georgia reports that native subterranean termites begin swarming in February or March, swarm during the day, and are not attracted to lights. Native swarmers are black and about three-eighths of an inch long from head to wingtip. Discarded wings on a sill or windowsill are a common sign. The termite swarm season guide covers how to tell a swarm from other flying insects.
What happens in April and May?
Ants trail indoors after rain, the first mosquito containers fill, and fire ant mounds appear in lawns. Late May can bring a Formosan swarm, which UGA says is rare in Georgia.
April brings household ants that trail indoors after rain, and the first mosquito containers begin to fill after spring showers. Carpenter bees are another spring visitor to deck rails and fascia boards. This calendar makes no claims about their numbers or life cycle.
May brings fire ant mounds into view in many lawns, and the ants are a nuisance that the University of Georgia describes as managed rather than eliminated. The Formosan termite is a different case. UGA reports that it swarms at night in late May or early June and is drawn to light, but it is rare in Georgia, and railroad crossties in a landscape do not imply its presence. A swarm seen in that window is worth a technician's look rather than a cause for alarm.
What happens in June and July?
Mosquito season is in full swing. Adults can emerge in about three days in Georgia summer heat, so UGA advises walking the yard twice a week. Smokybrown and American cockroaches can move in from tree holes and leaf litter in heat and rain.
The Asian tiger mosquito is Georgia's most common and widespread mosquito pest, according to UGA Extension, and it is a container breeder. Its breeding sites are things that hold water around a house. A yard walk twice a week gives a chance to empty new containers before a new generation emerges, which a single weekly check can miss. The mosquito control service covers what a technician checks in a yard during this stretch.
The roach part of summer follows the weather. Smokybrown and American cockroaches can move in from tree holes and leaf litter in heat and rain, so outdoor habitat is a more useful place to look than the kitchen. The palmetto bug guide explains why the outside of the house matters for these insects. Smokybrown and American cockroaches are mostly a summer question for the outside of the house, which is why the calendar places them in June and July rather than in the kitchen-focused months.
What happens in August and September?
August into mid-September is the reported peak for the southern house mosquito, which breeds in storm drains and polluted water. This calendar makes no claims about yellowjacket nests.
Georgia's West Nile carrier is the southern house mosquito. Regional news reports describe it as breeding in storm drains and polluted water, with a peak later in summer, roughly from August into mid-September. It is a different mosquito from the day-biting one in the yard, and the mosquito guide separates the two for that reason.
Gwinnett County has had a human West Nile case, and the county health department's response was an education campaign. Its advice was to tip and toss, use DEET repellent, wear loose long sleeves and pants, limit outdoor time and use screens on doors and windows. The mosquito season guide goes through that advice and what it means for a back yard.
What happens in October?
Rodents push indoors as nights cool, and wasps look for shelter. A termite warranty with annual inspections is worth checking against its contract for the date of the next visit.
Rodents move toward houses as nights cool, according to UGA Extension, which reports that the house mouse, the Norway rat and the roof rat all live in Georgia. Rats and mice usually hide by day and come out at night. A small hole with chewed edges is a sure sign that a rodent has settled in, and that sign is worth acting on before the cold weather brings more of them inside.
A termite warranty that includes annual inspections should be checked against its own contract for the date of the next visit. Georgia's rules require a written contract for each termite job, and a warranty-only contract carries an annual inspection and a clear statement about inspection, treatment and repair limits. The rodent control service covers the sealing and trapping side of the same month.
What happens in November and December?
A mild winter means ants, roaches and spiders can carry on indoors. The reference point for the next freeze is early April, not autumn, so the calendar does not end with the season.
Winter in the area is usually mild. Ants, roaches and spiders can carry on indoors through November and December, because a heated house can keep them active. The calendar does not treat winter as a pause in pest work. The nearest reference point is the last freeze, which usually falls in early April, and the calendar works from that date rather than from the calendar year. For a house with a crawl space, that is a reason to keep an eye on damp areas through the cold months, because moisture under the floor may not follow the calendar.
Rodents are still a winter subject, and UGA's guidance on keeping rodents out of the home applies at any time of year. Winter is also a sensible time to book a termite inspection ahead of the swarm season. Phones are answered 24/7 at (855) 974-4733, and a visit is scheduled when a technician is free rather than at a set time.
How should I use this calendar?
Use each month as a starting point, not a schedule. Each entry describes what is usually seen in that window, and local weather can move every date in it.
The calendar is built from University of Georgia material, Georgia state rules and a small number of regional news reports. Where a claim comes from UGA, the month says so. Where a claim is a general pattern, it is written as a pattern rather than a date. No calendar predicts a particular house, so a technician checks the yard and the crawl space on a visit before any plan is set.
Use the calendar to decide when to look. A termite inspection before February, a yard walk in the summer, a rodent check in October and a perimeter look in the winter cover most of what a homeowner can watch for. A visit the same day is possible when a technician is free, and no arrival time is promised for any month. The most useful test for any month is simple: has anything been seen that the calendar did not predict? If so, that sighting matters more than the month it falls in.
Frequently asked questions
When do termites swarm in Snellville?
According to the University of Georgia, native subterranean termites begin swarming in February or March and swarm during the day. They are not drawn to lights. Native swarmers are black and about three-eighths of an inch long. Formosan termites in Georgia swarm at night in late May or early June, but UGA says they are rare in the state.
When are mosquitoes worst in Gwinnett?
Mosquito pressure is highest in the warm months, when Asian tiger mosquito adults can emerge in about three days. UGA advises walking the yard twice a week in summer heat. Regional news reports describe the southern house mosquito, the Georgia West Nile carrier, as peaking from August into mid-September. The two mosquitoes have different breeding sites and different peaks.
When do rodents come into houses?
Rodents move toward houses as nights cool, which the calendar places in October and continues through the winter. UGA reports that the house mouse, Norway rat and roof rat all live in Georgia. Rats and mice usually hide by day and come out at night, and a small hole with chewed edges is a sure sign of occupancy.
Is there pest work to do in winter?
Yes. A mild winter means ants, roaches and spiders can carry on indoors through November and December. Winter is also a sensible time to book a termite inspection before the spring swarm season. The calendar uses early April, the usual last freeze, as its reference point rather than the end of the year.
How reliable is the weather in this calendar?
The climate figures in the calendar are hedged approximations from a third-party weather summary, not official normals. The last spring freeze window comes from a Georgia public broadcaster's reporting. Use both as a general picture of the year. Local conditions in a given summer can move every date.
What about carpenter bees and yellowjackets?
This calendar makes no sourced claims about carpenter bees or yellowjacket nests, because specific numbers and life-cycle timing are not part of what this site can state. A technician can look at a particular deck, fascia or yard and describe what is present. Ask for that look rather than relying on a general month.
Sources
- University of Georgia Extension
- University of Georgia Extension
- University of Georgia Extension
- Georgia Secretary of State
This guide is general information for Gwinnett County homeowners, not a substitute for an on-site inspection. Prices are estimates. See our disclaimer.