Scorpion Control

Start with geography, because "bark scorpion" means two different animals. In Arizona it means the Arizona bark scorpion, which University of Arizona Extension calls the only scorpion of medical concern in the United States. In Texas and the Midwest the same phrase means the striped bark scorpion, and Texas A&M AgriLife states there are no scorpions in Texas considered lethal to people. A Texas reader searching the phrase lands on Arizona-severity content.

The striped bark scorpion has two markings worth learning. Texas A&M describes two broad blackish longitudinal stripes down the back of the abdomen, plus a dark triangular mark on the front of the head region. Adults average about 2 and 3 eighths inches, around 60 mm. The base color is yellowish to tan, and juveniles are lighter.

The Arizona bark scorpion is light tan to yellow-brown and highly variable. University of Arizona Extension describes some individuals as pale and others darker with stripes or checkered patterning, with slender pincers and a long slender tail. Size is genuinely disputed between two Arizona authorities: UA Extension gives 2 to 3 inches including the tail, while the Arizona Poison and Drug Information Center says only an inch and a half at maturity. Both figures are published, so treat the range as unsettled.

Ignore the "small pincers and a thick tail means dangerous" rule. A 2022 analysis in Toxins found narrower pincers do track higher venom potency but found no significant relationship for tail proportions. In Arizona the rule actually inverts, because the dangerous species has a thin tail and the harmless desert hairy and stripedtail look-alikes are stouter. No US extension source endorses the shortcut.

A long-wave UV black light is the extension-recommended way to find them. University of Arizona Extension and UC IPM both state that scorpions glow brightly under ultraviolet light because the exoskeleton fluoresces, and that using a black light lets you locate them. UA recommends night sweeps between 8 and 11 pm in summer, with a caution about eye safety. Texas A&M confirms the striped bark scorpion fluoresces the same way.

Climbing explains where you find them. University of Arizona Extension states the Arizona bark scorpion is the only Arizona scorpion that can climb walls and ceilings, often holding a vertical position on walls or an upside-down position on all but the most slippery surfaces such as glass. The striped bark scorpion also climbs trees, walls and attics. Neither species burrows. That combination is why scorpions turn up in beds and bathtubs: they traverse ceilings and fall.

Harborage differs by region. In Arizona, look at block walls, weep screed, under bark, wood piles, garages, crawl spaces, shoes, bedding and under furniture. In Texas and the Midwest, Texas A&M points to under rocks, under boards and in debris outdoors, and notes that many indoor reports are associated with attics, with a summer move down from the attic into living areas.

Sticky boards are a California-specific recommendation. UC IPM endorses glue boards of about 8 by 5 and a quarter inches. No Texas or Midwest extension source reviewed recommends them for the striped bark scorpion, so treat them as a regional tool rather than general practice.

Scorpions do not damage a building. No university extension or federal agency source documents structural damage from any US scorpion. They do not chew, tunnel, nest in wood or gnaw wiring. The whole issue is entry and harborage, which is why extension guidance is about closing gaps rather than repairing anything.

The gaps that matter are the ones already in the wall. University of Arizona Extension, Texas A&M AgriLife, University of Missouri Extension and Clemson all point to the same list: cracks and utility penetrations, door and window screening, firewood stored elevated and away from the house, debris and trash removal, moisture problems, and gravel rather than mulch as groundcover.

Weep holes are a genuine disagreement between two extension services. University of Arizona says to screen them with coarse steel mesh and warns that the holes should not be plugged or sealed because they ventilate wall spaces. Texas A&M says to plug them. Screening satisfies both goals, so reconcile toward screening rather than sealing shut.

Sprays alone will not solve it. University of Arizona, UC IPM and Texas A&M agree insecticides on their own do not work. UC IPM gives the reason: scorpions hide in cracks and crevices during daylight hours, and adults resist pesticides because of their larger body size and thicker cuticle.

Can you tell what stung you from the mark?

No. Skin reactions to arthropod bites and stings are non-specific, and Texas A&M AgriLife states it is often very difficult to determine the cause with certainty without a specimen or an observation. A welt is not evidence of a scorpion. Finding the animal, or finding scorpions under a black light at night, is what settles it.

What does a striped bark scorpion sting feel like?

Like a bee sting for most people. Texas A&M describes stings as painful, producing local swelling and itching that may persist for several days, with effects ranging from mild to strong including edema, discoloration, numbness and pain lasting from several minutes to several days. The main risk with this species is an allergic reaction, as with bee and wasp stings, rather than an envenomation syndrome.

What does an Arizona bark scorpion sting do?

It produces immediate severe pain and tingling at the site, often with little or no swelling. That absence of swelling is the contrast with the striped bark scorpion. In severe cases the Anascorp prescribing information describes loss of muscle control, roving or abnormal eye movements, slurred speech, respiratory distress, excessive salivation, frothing at the mouth and vomiting. Neurotoxic effects typically develop within about 20 minutes and worsen over roughly four hours.

How often does a sting get serious?

Rarely, and children are the exception. The American Academy of Family Physicians reports that severe systemic envenomation occurs in less than 5 percent of stings and is more common in children. University of Arizona identifies young children and older adults as highest risk. An FDA-approved antivenom, Anascorp, has been available since 2011 for clinical signs of scorpion envenomation.

What should you do after a scorpion sting?

CDC and NIOSH, University of Arizona Extension and the Arizona Poison and Drug Information Center all advise washing with soap and water, applying a cool compress, and taking oral analgesics. Do not apply a tourniquet. Call Poison Control at 1-800-222-1222, which is free, confidential and open 24 hours. University of Arizona advises calling 911 if a child is stung by a bark scorpion.

One circulating instruction is wrong. The "do not use ice packs" rule that appears in consumer scorpion content comes from a snake-bite protocol, not arthropod first aid. University of Arizona, the Arizona Poison Center and Texas A&M all actively recommend a cool compress for scorpion stings.

This is general information, not medical advice. PestChief does not diagnose stings, and no one can name a pest from a mark on skin. If a sting concerns you, or if the person stung is a young child, contact a healthcare professional or Poison Control.

1. Shake out shoes, bedding and towels: Stings often happen when someone puts on a shoe or picks up laundry from the floor. Keep both off the floor.
2. Move the bed away from the wall: Bark scorpions climb. Keeping beds and cribs clear of walls and bedskirts off the floor reduces night encounters.
3. Clear harborage against the house: Move firewood, bricks, pots and landscape rock away from the foundation and off the wall line.
4. Note where you find them: Record each sighting and location. Patterns point to the entry route the technician needs to seal.
5. Know the sting plan: Keep your local poison control number handy, and seek medical advice for stings to young children or with symptoms beyond local pain.

Which scorpions matter in the US?

Scorpions are a regional pest concentrated in Arizona, Nevada, southern California, New Mexico and parts of Texas. Most species deliver a painful sting comparable to a wasp. The Arizona bark scorpion is the species that changes how control is done, because it is the one with medically significant venom in the region and, unlike most scorpions, it climbs walls, ceilings and furniture.

Anyone stung who develops symptoms beyond local pain, and any sting to a young child or an older adult, should get medical advice promptly. Poison control centers handle these calls routinely.

Why does sealing matter more than spraying for scorpions?

Bark scorpions squeeze through gaps thinner than a credit card and are not reliably controlled by residual products alone, partly because they walk on the tips of their legs and pick up less surface residue than insects do.

The durable answer is physical: seal door sweeps, weep holes with screens that still drain, expansion joints, plumbing and electrical penetrations, roof tile lines, weep and attic vents, and gaps at block wall caps. Companies serving the Phoenix, Arizona and Las Vegas, Nevada markets often sell a home-sealing package precisely because treatment without it disappoints.

What does professional scorpion service include?

• A night inspection with a black light, because scorpions fluoresce and are far easier to find after dark
• Interior and exterior sealing of gaps, weep holes, door sweeps and penetrations
• Treatment of harborage: block walls, landscape rock, pool equipment, wood piles, irrigation boxes
• Treatment of the insect prey base, since scorpions follow crickets and roaches
• Recurring exterior service, usually monthly or every other month
• Advice on landscape rock, irrigation, outdoor lighting and storage against the wall

When are scorpions most active?

Activity runs from roughly March through October in the desert Southwest, peaking in July and August when scorpions hunt at night and move toward cooler, more humid spots, which frequently means inside a house. Monsoon rains push them out of burrows and produce a noticeable spike in sightings.

In winter, scorpions become inactive and may overwinter inside wall voids and attics, which is why homeowners sometimes find them indoors on an unusually warm winter day.

Is scorpion-specific service available in my area?

Scorpion-specific service, particularly black-light inspection and home sealing, is concentrated in the Southwest markets where scorpions are a real issue. Outside Arizona, Nevada, New Mexico, southern California and parts of Texas, expect general pest companies rather than scorpion specialists.

PestChief matches on coverage and on whether the company handles scorpions, never on price. Where no scorpion specialist covers a ZIP code, the request goes to one independent local pest control company that does handle the pest.

How much does scorpion control cost?

Initial service commonly runs $150 to $400, with recurring visits at $60 to $120. Home-sealing packages are quoted separately and range from several hundred to a few thousand dollars depending on the house. These are national estimates from published sources, not a PestChief quote. The company that inspects your home sets its own price.

Does spraying get rid of scorpions?

Treatment alone usually falls short. Scorpions pick up limited surface residue and enter through very small gaps. Sealing the structure, combined with harborage treatment and cutting their insect prey, produces the real reduction.

Are scorpions in my house dangerous?

Most US scorpion stings produce localized pain similar to a wasp sting. The Arizona bark scorpion is the medically significant exception in the Southwest, and stings to young children or older adults warrant prompt medical advice.

Why do I see scorpions after it rains?

Monsoon rain floods burrows and harborage, pushing scorpions to higher and drier ground, which often means a house perimeter, a garage or a wall void. Sightings commonly spike for a week or two after heavy rain.

How do scorpions get inside?

Through weep holes, gaps under doors, expansion joints, plumbing and electrical penetrations, roof tile lines and attic vents. Bark scorpions can pass through gaps thinner than a credit card and can climb to reach them.

Does a black light inspection actually help?

Yes. Scorpions fluoresce under ultraviolet light, so a night inspection finds harborage and travel routes that a daytime walkthrough misses entirely. Many Southwest companies include it in the initial service.

Is recurring service necessary for scorpions?

In high-pressure desert neighborhoods, generally yes. Scorpions continually move in from surrounding desert and landscaping, so monthly or bi-monthly exterior service plus good sealing is the normal pattern.

Does PestChief treat scorpions?

No. PestChief does not spray, seal or inspect. PestChief passes your ZIP code and your pest to one independent local pest control company that covers your address and handles scorpions, and that company contacts you directly. The service is free to the homeowner.

• Texas A&M AgriLife Extension
• UC Statewide IPM Program, Home and Landscape pests
• National Pest Management Association
• University of Arizona Cooperative Extension AZ1768, Scorpions
• Texas A&M Field Guide to Common Texas Insects, Striped Bark Scorpion
• Texas A&M AgriLife E-362, Scorpions
• UC IPM Pest Notes 74110, Scorpions
• University of Missouri Extension G7364, Scorpions
• Clemson HGIC 2441, Scorpion Control
• CDC NIOSH, Insects and Scorpions at Work
• Texas A&M AgriLife ENT-3006, Diagnosing Mysterious Bug Bites
• American Academy of Family Physicians, Arthropod Bites and Stings, 2022
• US Food and Drug Administration, Anascorp
• DailyMed, Anascorp prescribing information
• National Capital Poison Center, Scorpions
• Forde et al., Toxins, scorpion morphology and venom potency