The 10 worst pests to have in your house are termites, bed bugs, cockroaches, rodents, mosquitoes, fleas, ants, stinging insects, ticks and venomous spiders, because each one either damages the structure, affects health or is hard to eliminate once established. Saela Pest Control is a residential and commercial pest control company, based in Orem, Utah, that treats all ten. This guide explains how to identify each pest, why it causes problems and what professional pest control does about it, starting with the pests that damage homes.
1. Termites: Hidden Wood Damage
Why They’re Among the Worst Pests
Termites rank high because they damage wood from the inside, often for years before anyone notices. Subterranean termites feed out of sight in soil and wood, and Mississippi State University Extension’s guide to signs of termite infestation notes that a building is usually infested for some time before any signs become obvious.
That delay is what makes termites costly: damage builds while the colony grows. Regular inspections are the most practical defense, since a clean-looking house doesn’t prove there are no termites.
Identifying a Termite Problem
Watch for these warning signs of a termite infestation:
- Wood that sounds hollow when tapped or feels soft when probed
- Mud tubes on foundations, piers, crawl space walls or plumbing
- Swarmers or shed wings near windows and doors indoors
- Narrow, sunken lines or small spots of dried mud on painted drywall
- Sagging floors or damaged door frames, which can also be wood rot
Professional Treatment Options
Termite treatment should be done by a licensed professional; the EPA’s termite guide notes that firms offering termite services must be licensed by your state and lists soil treatments, baits and wood treatments among the options. Saela’s termite packages use Trelona bait stations, with a Termidor perimeter treatment in the upgraded package.
2. Bed Bugs: Notorious Hitchhikers
Why Bed Bug Infestations Are So Hard
Bed bugs are among the hardest household pests to eliminate because they hide in mattress seams, furniture and cracks and travel easily in luggage and secondhand furniture. They feed on blood, mostly at night, and their bites cause itching and lost sleep.
The good news is that the CDC’s overview of bed bugs notes they are not known to spread disease to people. The CDC recommends contacting a professional pest control company experienced with bed bugs for an infestation.
Signs You Have Bed Bugs
Be alert to these signs of bed bugs:
- Itchy bite marks, which the CDC notes can appear one to several days after the bite
- Rusty or dark spots on mattresses and sheets
- Small blood spots on bedding
- Shed skins and eggs around bed frames and mattress seams
- A sweet, musty odor where infestations are heavy
Effective Treatment Strategies
Bed bug control usually takes more than one visit. Saela’s bed bug programs pair repeated treatments with laundering and vacuuming by the customer between visits, because preparation helps each treatment reach hiding bugs.
3. Cockroaches: Resilient Health Pests
Why They’re Considered Among the Worst Pests
Cockroaches are hard to control because they hide in warm, humid places near food and water and multiply quickly. UC IPM’s guide to cockroaches calls them significant public health pests and notes they have been identified as risk factors for asthma in children.
Their droppings and body parts can trigger asthma, and proteins in their feces and saliva can cause allergic reactions. That health effect is the main reason to treat a cockroach problem promptly.
Identifying Cockroach Species
UC IPM describes the most common household species this way:
- German cockroaches: about 1/2 inch, light brown with two dark stripes behind the head, found in kitchens and bathrooms
- American cockroaches: about 2 inches and reddish-brown, usually in sewers and drains, sometimes entering buildings
- Oriental cockroaches: about 1 1/4 inches and almost black, in cool, damp places such as basements and drains
- Brownbanded cockroaches: about 1/2 inch with light bands, often near appliances and inside furniture rather than kitchens
Professional Control Methods
Cockroach control works best with integrated pest management: inspection, sanitation, sealing and baits placed where roaches feed. Saela’s German cockroach treatment uses gel baits, crack-and-crevice applications, monitoring devices and a follow-up visit.
4. Rodents: Rats and Mice
The Problems Rodents Cause
Rats and mice cause damage by gnawing and nesting, and they contaminate food and surfaces with droppings and urine. Small openings are enough to let them in; the CDC’s guide to sealing up against rodents notes that mice can fit through a hole the width of a pencil.
Rodents can also spread disease. The CDC notes that people get hantavirus from contact with rodents’ urine, droppings and saliva, and that the deer mouse is its most common carrier in the United States.
Signs of Rodent Activity
Be vigilant for these signs of rodents:
- Droppings along walls, in drawers or in cupboards
- Gnaw marks on food packaging, wood or wiring
- Scratching sounds in walls or ceilings, especially at night
- Nests made of shredded paper, fabric or insulation
- A musky odor in enclosed spaces
Professional Rodent Management
Lasting rodent control means sealing the way in, not only trapping. Saela’s rodent exclusion service inspects for access points, repairs openings and places traps for rodents still inside, and Saela also offers attic and crawl-space clean-outs after rodent activity.
5. Mosquitoes: Disease-Carrying Biters
More Than Just a Nuisance
Mosquitoes make the list because some can spread germs that cause infections such as dengue, malaria and West Nile virus, according to CDC guidance on mosquito control at home. Even where disease risk is low, their bites keep people indoors on summer evenings.
Mosquitoes need water to develop, so the most useful control happens at the larva stage. Removing standing water around the home reduces how many adults emerge.
Controlling Mosquito Populations
Mosquito control starts with breeding sites:
- Once a week, empty and scrub, turn over, cover or throw out anything that holds water
- Keep swimming pool water treated and circulating
- Clear gutters and fix low spots where water pools
- Keep grass mowed and shrubs trimmed to reduce shady resting spots
Professional Mosquito Services
Professional treatment targets the places adult mosquitoes rest. Saela’s mosquito mist treatments target resting sites such as shaded foliage and areas beneath porches, alongside guidance on reducing standing water.
6. Fleas: Persistent Parasites
Why Fleas Are Among the Worst Pests to Deal With
Fleas are hard to eliminate because much of the population lives off the pet, as eggs, larvae and pupae in pet bedding and carpets. UC IPM’s guide to fleas notes that the cat flea is the most common flea on both cats and dogs, and that insecticides don’t kill pupae, so new fleas keep emerging for about two weeks after treatment.
Fleas can cause allergic dermatitis in pets and are intermediate hosts for dog and cat tapeworms. People get itchy bites too, often around the ankles.
Signs of a Flea Infestation
Look for these signs if you suspect fleas:
- Pets scratching, biting or licking themselves often
- Small dark insects jumping on carpets, furniture or pets
- “Flea dirt,” dark specks of flea droppings, in pet bedding
- Itchy bites around the ankles and lower legs
- Hair loss or skin irritation on pets
Professional Flea Treatment
Flea control works only when the pet and the home are treated together, so ask your veterinarian about the pet and a professional about the home. Saela’s flea treatment uses an insect growth regulator to stop fleas from reproducing, along with follow-up treatments and identification of indoor or outdoor infestation sources.
7. Ants: Persistent Invaders
From Nuisance to Structural Pest
Most ants are a nuisance, but some species cause real damage or sting. Carpenter ants hollow out wood to nest and may cause considerable damage, according to UC IPM’s guide to ants, and the red imported fire ant is an aggressive stinging ant.
Ants are hard to eliminate with sprays because the colony and its queens stay hidden. UC IPM explains that slow-acting baits work better, since workers carry them back to the nest.
Common Household Ant Species
UC IPM describes these common household ants:
- Carpenter ants: large, 1/4 to 1/2 inch, black or red and black, nesting in stumps, firewood and hollow doors or window frames
- Fire ants: reddish with a dark brown abdomen, nesting in soil mounds with several openings, and stinging aggressively
- Pharaoh ants: tiny, yellow to orange, nesting in wall and cabinet voids
- Odorous house ants: about 1/8 inch, dark brown to black, with a strong odor when crushed
- Pavement ants: dark brown to black, building mounds along sidewalks and foundations
Professional Ant Management
Professional ant control starts with identifying the species, because the right bait and nest treatment depend on it. Saela’s ant control follows its integrated pest management cycle of identification, monitoring, targeted treatment and evaluation.
8. Stinging Insects: Wasps, Hornets and Bees
Dangerous When Nesting Near Homes
Stinging insects become a serious problem when they nest near doors, decks or play areas. Reactions to stings range from short-term pain to life-threatening allergic responses, UC IPM’s guide to yellowjackets and other social wasps explains, and defensive behavior increases late in the season as colonies grow.
UC IPM also advises that when a wasp nest must be eliminated, it is easiest and safest to call for professional help. That is especially true for nests in walls or underground.
Identifying Common Stinging Insects
Learn to recognize these common stinging insects:
- Yellowjackets: black and yellow, often nesting in old rodent burrows or wall voids
- Paper wasps: slender, with open umbrella-shaped nests under eaves, and much less defensive than yellowjackets
- Baldfaced hornets: black with ivory-white face markings, building gray, football-shaped paper nests in trees and shrubs
- Honey bees: important pollinators, so ask a professional before anyone treats a bee nest
- Carpenter bees: large bees often mistaken for bumble bees
Professional Removal Services
A professional can identify the insect, treat or remove the nest with the right protective gear and timing, and look for other nesting sites. Saela offers wasp control for nests near the home.
9. Ticks: Tiny but Dangerous
Serious Disease Vectors
Ticks are dangerous mainly because of the diseases they can carry, including Lyme disease. The CDC’s tick prevention guidance notes that ticks live in grassy, brushy or wooded areas, and even on animals, which brings them close to yards and pets.
Ticks are small and easy to miss until they attach. Regular checks after time outdoors are the simplest protection.
Preventing Tick Encounters
The CDC recommends these steps to reduce tick exposure:
- Mow often and remove leaf litter and tall grass
- Place a 3-foot-wide barrier of wood chips or gravel between lawns and wooded areas
- Use an EPA-registered repellent and consider clothing treated with permethrin
- Check your body, children and pets after outdoor activities
- Shower within two hours of coming indoors and dry clothes on high heat
Professional Tick Control
Professional treatment focuses on the edges of the yard where ticks live, such as tall grass, brush and shady areas with leaf litter. Saela offers tick control; ask which areas of the yard a plan covers.
10. Spiders: Beneficial but Sometimes Dangerous
When Spiders Become Problematic
Most spiders are beneficial predators, but black widows and brown recluses can cause serious bites. The CDC’s guidance on venomous spiders names them as the two venomous spiders in the United States and notes that most bites happen when a spider is trapped or touched.
A large number of spiders indoors often means there are plenty of other insects for them to eat. Reducing those insects and the clutter where spiders hide addresses the cause.
Identifying Spiders That Matter
Learn to recognize these spiders:
- Black widow: shiny black with a red or orange hourglass on the underside of the abdomen
- Brown recluse: brown, with a dark violin-shaped mark and six eyes instead of eight
- Wolf spider: large, brown ground hunter, often mistaken for a brown recluse but not medically important
- Common house spiders: most are harmless, and many have jaws too small to bite people
- Any spider you can’t identify: save it so a professional can identify it
Professional Spider Management
Professional spider control combines identification, removing webs and egg sacs, reducing clutter and sealing cracks, and targeted treatment where spiders shelter. Saela’s spider control starts with identifying the species.
Why DIY Methods Often Fall Short
The Limitations of Store-Bought Solutions
Store-bought products usually reach only the pests you can see, not the colony, nest or eggs. For ants and cockroaches, sprays can even scatter the pests, which is why UC IPM recommends baits instead.
Misusing pest control products also creates risks for people and pets. Every product should be used exactly as its label directs. Our article on the importance of pest identification explains why identifying the pest comes before choosing a treatment.
When to Call Professional Pest Control
Consider calling a professional when:
- A problem continues after several attempts at DIY treatment
- You’re dealing with venomous spiders, stinging insects or a nest near the house
- You see signs of termites or carpenter ants
- You need a professional inspection, such as before buying or selling a home
- You want ongoing prevention rather than reacting to each problem
Why Hire Saela Pest Control for Serious Pest Problems?
Expertise That Makes the Difference
Saela’s treatment protocols are developed by Dennis Weiss, Saela’s board-certified entomologist, who also trains its technicians and conducts service-quality audits. He holds the Entomological Society of America’s Board Certified Entomologist credential in urban and industrial entomology.
Saela uses an integrated pest management cycle of identification, monitoring, targeted treatment and evaluation. That approach includes sealing entry points and reducing the food, water and shelter that support infestations.
Inspection, Follow-Up and Return Visits
Every Saela plan includes a 50+ point property inspection covering entry points, nesting sites and structural gaps. Saela also offers no-charge return visits for covered pests between scheduled services while a plan is active.
For homes dealing with more than one pest, that combination of inspection, targeted treatment and follow-up addresses the conditions behind the problem. In a February 2024 Google review, Danny Vian wrote, “John did a great job,” describing the technician as thorough and courteous and saying he would like John to keep servicing his property.
Safety and Credentials
Pest control should always follow the product label, and you can ask your technician about re-entry times for children and pets. Saela is listed in QualityPro’s directory of accredited pest management companies, and its Lakewood, Washington location is rated 4.8 out of 5 from 1,164 Google reviews as of October 2026.
If you’re dealing with any of these pests, book a call with Saela to schedule an inspection. Saela’s pricing page explains how plans are quoted.
Frequently Asked Questions
What is the most destructive household pest?
Termites are generally the most destructive household pest, because they damage a home’s wood structure from the inside and can go unnoticed for years. Other pests mainly cause nuisance or health problems rather than structural damage, although carpenter ants and rodents can also damage wood and wiring.
How quickly can a pest infestation develop?
The timeline varies by pest, but some, such as German cockroaches and fleas, can build large populations within a few weeks of arriving. UC IPM notes that a German cockroach egg case holds about 30 young and a female can produce a new one every few weeks, while termite damage builds over months or years.
Are natural or organic pest control methods effective?
Natural methods such as sanitation, sealing gaps and removing standing water are effective prevention, but they are rarely enough on their own for an established infestation. Some lower-impact tools, such as Bti for mosquito larvae or insect growth regulators for fleas, are used within professional programs; our guide to health threats posed by pests explains why established infestations deserve prompt attention.
How often should I schedule professional pest control services?
Most homes do well with regular visits through the year, with the schedule depending on the pests, the property and the plan. Saela’s Protection Program, for example, includes interior and exterior treatments every other month or quarterly, depending on the plan selected.
Can pests return after professional treatment?
Yes, new pests can arrive after any treatment, which is why ongoing prevention, regular inspections and follow-up visits matter. Saela offers no-charge return visits for covered pests between scheduled services while a plan is active; the Saela guarantee page explains the details.
Who wrote this article?
Devin Hutchings (Marketing Director at Saela Pest Control) wrote this article.
Devin leads Saela’s marketing and growth strategy. He brings more than 15 years of marketing experience across Uber, C.R. England, Lugg, and Neighbor. His background spans customer acquisition, retention, and developing marketing channels for service businesses and consumer marketplaces.
