Top Summer Pests In Southern Utah And How To Prevent Them

Summer in southern Utah is long and hot. From June into September, afternoons regularly push past 100 degrees, natural water is hard to find outside of the rivers and washes, and the most dependable water in most neighborhoods is the water we put down ourselves through irrigation. Monsoon storms add short bursts of moisture in July and August.

Most of what follows comes back to those facts.

Ants

The most common summer call, by a long way.

Heat sends colonies searching for water, and irrigated beds and turf deliver it right up against the house. That is also why indoor trails tend to show up in kitchens and bathrooms. Harvester ants are another summer issue in yards, with painful stings and large bare mounds.

Prevention:

• Aim sprinklers and drip lines so nothing wets the slab or walls
• Fix leaking emitters and hose bibs right away
• Keep a strip of open ground or gravel along the house with nothing planted against it
• Trim plants so they do not touch the walls
• Seal pipe openings and cracks in the slab and stucco
• Follow trails back to where they enter instead of spraying them

Wasps And Yellowjackets

Paper wasps and yellowjackets are the main stinging insects around homes here. Nests started in spring reach full size and peak defensiveness from late summer into fall. Africanized honey bees have also been found in Washington County, so any bee colony near the house deserves caution.

Prevention:

• Check eaves, patio covers, tile roof edges, play sets, and grills in spring while nests are small
• Keep trash cans closed and rinse recycling
• Clean up right after eating outside
• Pick up fallen fruit
• Fix water leaks and misters that pull wasps to the patio
• Watch for insects flying in and out of one spot before mowing or trimming

Spiders

Spiders follow the insects, and insects peak in summer. Outdoor lights concentrate prey and build spider populations right around the doors. Black widows are especially common in garages, block walls, utility boxes, and under patio furniture.

Prevention:

• Switch outdoor bulbs to warm white 2700K or amber
• Use motion sensors instead of leaving lights on all night
• Knock down webs from eaves and corners regularly
• Cut down clutter in the garage and storage areas
• Seal gaps at doors, windows, and along the slab

Scorpions

Arizona bark scorpions are the one to take seriously in St. George. They are the most venomous scorpion in North America, and while stings are rarely dangerous for healthy adults, they are very painful and can be serious for small children, older adults, and people with health conditions. Bark scorpions climb walls and ceilings and hide in block walls, rock landscaping, and lava rock. Desert hairy scorpions are much larger but less of a concern.

Prevention:

• Clear rock piles, boards, and stored materials away from the walls
• Keep firewood raised and away from the house
• Install tight door sweeps and weather stripping, since scorpions fit through very thin gaps
• Cut down the insects they feed on
• Shake out shoes, gloves, and towels left in the garage or outside
• Pull beds a few inches from the walls and keep bedding off the floor

Earwigs

They depend heavily on moisture, so watered landscaping is perfect for them. Harmless despite the pincers, but they can come inside in large numbers.

Prevention:

• Thin out mulch along the foundation
• Water early in the morning so surfaces dry during the day
• Clear thick ground cover away from the walls
• Seal gaps under doors

Crickets

Their numbers build through summer and peak in late summer and fall. Beyond the noise, they are a main food source for scorpions and black widows, so controlling crickets helps with both.

Prevention:

• Cut back outdoor lighting
• Clear plants and debris from along the walls
• Seal openings at ground level, especially garage door corners

Flies

House flies around trash, fruit flies around produce, and drain flies from buildup in pipes.

Prevention:

• Keep trash cans closed and clean, and keep them away from doors
• Refrigerate ripe fruit
• Clean drains with an enzyme cleaner rather than bleach
• Repair screens
• Pick up pet waste promptly

Mosquitoes

Less of a problem here than in humid places, but they breed wherever water sits, including along the Virgin and Santa Clara Rivers, in washes after storms, and in backyard containers. West Nile virus shows up in Utah in some summers, so it is worth limiting bites. The Southwest Mosquito Abatement District handles public mosquito control; around your own home, standing water is the thing to manage.

Prevention:

• Dump water from saucers, buckets, tarps, and low spots, especially after monsoon storms
• Change pet water and birdbaths often
• Keep pool and fountain water circulating
• Repair screens

Rodents

Most people do not think of rodents as a summer problem, and that is a mistake. Mice and pack rats build their numbers outside all summer, which sets up the move indoors once fall nights cool down. Pack rats also nest under car hoods and chew wiring in any season.

Prevention:

• Keep plants trimmed back from the house and roof
• Store firewood raised and away from the house
• Close up trash and pet food
• Check under the hood of cars that sit for a while
• Start sealing gaps in late summer instead of waiting for cooler weather

The Two Levers That Matter Here

Almost everything above comes down to the same two things.

Water. In the Mojave Desert, irrigation is the main water source available to pests, and anything wet against the foundation pulls activity toward the house. Adjusting sprinklers and fixing leaks does more for summer pest pressure than any other single step.

The perimeter strip. A clear, well-kept strip along the house cuts off the route pests take from the yard to the walls, makes activity easy to spot, and lets perimeter treatments work the way they are supposed to.

Get those two right and the rest of the list gets much shorter.

If summer pests are making their way into your St. George or Washington County home, contact Butter Pest Control. We will find what is drawing them in and fix the conditions, not just the symptoms.