California is home to several scorpion species, found from the desert floors of the southeast to elevations above 7,000 feet. Most are harmless enough that a sting feels similar to a bee sting, but one species found near the Arizona border carries venom that poses a real health risk. Whether you’ve spotted one in your yard or you’re moving to a new part of the state, here’s what you need to know.
Species You’ll Find in California
Three scorpion species account for most encounters in the state, and they vary widely in size, habitat, and danger level.
The stripedtail scorpion is one of the most common scorpion species in the entire United States. It’s widespread across Southern California and Arizona. These are small, yellowish-brown scorpions that blend easily into sandy or rocky ground. Their sting is painful but not medically dangerous for most adults.
The Arizona hairy scorpion is the largest scorpion in North America, reaching up to about 5.5 inches long. Its name is a bit misleading for Californians, because it’s a common desert species throughout Southern California. It has been reported in Imperial, Inyo, Kern, Los Angeles, Riverside, San Bernardino, and San Diego counties. Despite its intimidating size, its venom is relatively mild, roughly comparable to a wasp sting.
The bark scorpion is the one to take seriously. It’s the only scorpion in the southwestern U.S. with venom that is dangerous to people. In California, it occurs only in the extreme southeastern corner of the state, along the Arizona border. If you live in the greater Los Angeles area, the Central Valley, or Northern California, you’re well outside its range. But if you’re near the Colorado River border towns, it’s a legitimate concern.
Several other, less common species also live throughout the state, but they’re rarely encountered and their stings are not considered medically significant.
Where and When Scorpions Are Most Active
Scorpions are nocturnal hunters. They emerge after dark to prey on crickets, cockroaches, and other small arthropods. During the day, they hide under rocks, in cracks, beneath bark, or inside any dark, sheltered space they can find.
Warm months are peak scorpion season. As temperatures rise in late spring and summer, scorpion activity ramps up considerably. In urban and suburban areas, scorpions often congregate in higher numbers around buildings than in the open desert, because irrigated landscapes and the structure of homes provide both moisture and shelter. Hollow block perimeter walls, in particular, create ideal hiding spots.
If you live in a Southern California desert community, finding a scorpion inside your home during summer is not unusual. They’re attracted to the water sources and cooler temperatures that homes provide.
What a Sting Feels Like
Most California scorpion stings cause immediate, sharp pain at the sting site, along with numbness, tingling, slight swelling, and warmth. For the common species (stripedtail and hairy scorpions), these symptoms typically fade within a few hours to a couple of days, much like a bad bee sting.
A bark scorpion sting is a different experience. Beyond the local pain, it can trigger whole-body symptoms: muscle twitching or jerking, difficulty breathing, drooling, sweating, slurred speech, nausea, vomiting, rapid heart rate, and restlessness. Young children are especially vulnerable and may become inconsolable. In rare cases, a severe allergic reaction can develop, with hives and breathing difficulty.
If a child is stung by any scorpion, contact Poison Help at 800-222-1222 immediately. Adults should seek medical care if they develop breathing problems or if symptoms persist for more than a week.
Identifying a Bark Scorpion
Bark scorpions are smaller and more slender than the hairy scorpion, typically light tan or yellowish, and about 2 to 3 inches long. Their most distinctive behavior is climbing. Unlike most other scorpion species, bark scorpions are skilled climbers and can scale walls, trees, and rough surfaces. If you find a scorpion on a vertical surface or clinging to the underside of an object, it’s more likely to be a bark scorpion. The stripedtail and hairy scorpions are ground dwellers that rarely climb.
A UV blacklight is one of the easiest identification tools. All scorpions glow a bright blue-green under ultraviolet light, making a cheap blacklight flashlight invaluable for nighttime inspections around your property.
Keeping Scorpions Out of Your Home
Physical exclusion is the most effective strategy. Scorpions can squeeze through surprisingly small gaps, so a thorough inspection of your home’s exterior is the first step. Walk slowly around the foundation and look for cracks and crevices, especially around doors, windows, and where utilities enter the wall. Seal everything with caulk or spray foam.
Pay special attention to these entry points:
- Door and window gaps. Install or replace weather stripping. Make sure window screens fit tightly into the frames with no gaps at the edges.
- Weep holes. These small openings in brick, stone, or stucco walls allow water drainage but also allow scorpions inside. Plug them with steel wool, copper mesh, or screen wire, which still permits airflow while blocking entry.
- Foundation cracks. Even hairline cracks in concrete or stucco can be wide enough. Caulk them.
Inside your home, reduce clutter in garages, closets, and storage areas. Scorpions seek dark, tight spaces during the day. Shake out shoes, gloves, and clothing that have been sitting on the floor, especially in garages or sheds.
Outside, remove debris piles, stacked wood, and large rocks near the foundation. Trim vegetation so it doesn’t touch the house. These steps eliminate the hiding spots that bring scorpions close to your walls in the first place.
Chemical and Natural Deterrents
Food-grade diatomaceous earth can be spread around the perimeter of your home and near potential entry points. It works by damaging scorpions’ exoskeletons, causing them to dehydrate. It’s non-toxic to people and pets but needs to be reapplied after rain.
Some natural essential oils, including lavender, cinnamon, peppermint, and cedar, are said to repel scorpions when diluted and sprayed around entry points. Evidence for their effectiveness is mostly anecdotal, so they work best as a supplement to physical exclusion rather than a standalone solution.
Professional pest control is worth considering if you’re in a high-density area. Synthetic products tend to last longer and work more effectively than natural alternatives against scorpions. Reducing the population of prey insects (crickets, roaches) around your home also helps, since fewer food sources mean fewer scorpions have a reason to stick around.