Arizona bark scorpions: what West Valley homeowners should know.

Identifying bark scorpions

Centruroides sculpturatus

Arizona bark scorpions are slender and light colored, usually tan or yellow-brown, with thin pincers and a long, skinny tail. Adults run about two to three inches. Hold a UV flashlight over one at night and it glows a bright blue-green, which is the easiest way to find them on a wall or in a yard.

Unlike most scorpions, bark scorpions climb. They scale stucco, block walls, tree trunks and even ceilings, then slip through gaps as thin as a credit card. They hunt at night, rest in cool, tight spaces during the day, and are most active from roughly spring through fall. In cooler months they often cluster together in sheltered spots.

West Valley homes give them everything they want. New builds go in next to open desert and disturb existing populations. Rock landscaping, irrigation, citrus trees and block walls hold moisture and insects, and the gaps under doors, around plumbing and at the roofline lead straight inside. A scorpion in the bathtub usually means there are more outside.

Why they matter

A bark scorpion sting is painful, and young children and older adults are especially at risk. Stings can be medically significant: call Poison Control at 1-800-222-1222, or 911 for a severe reaction. The goal of treatment is fewer scorpions inside, where people get stung at night or when reaching into shoes and laundry.

Signs of activity

• Scorpions on walls, ceilings or in tubs and sinks, especially at night
• Glowing scorpions along block walls or rock beds when you check with a UV light
• Plenty of crickets, roaches and other insects they feed on around the house
• Scorpions in garages, closets, shoes or piles of laundry on the floor
• Sightings that pick up after you move in next to open desert or new construction

Prevention tips for Arizona homes

• Install weatherstripping and door sweeps so there is no gap under exterior and garage doors
• Seal cracks in stucco, gaps around plumbing and wiring, and openings at the roofline and weep screed
• Keep rock, firewood, pavers and yard debris stacked away from the foundation and block walls
• Trim citrus, palms and shrubs so branches do not touch the roof or walls
• Fix irrigation leaks and drippers that keep soil wet next to the house
• Move beds and cribs off the wall, keep bedding off the floor and shake out shoes before you put them on

When to call a pro

If you are finding scorpions inside more than once in a while, the population outside is established. Bryce treats the exterior and the entry points, checks the attic and garage, and points out the gaps worth sealing. Monthly plans include free re-service between visits.