Should you kill a false widow spider?

Imagine walking out to the garage on a crisp autumn evening to grab an old pair of gardening boots, only to spot a dark, shiny spider hunkered down in the corner of the shelf. Your immediate instinct might be to reach for a rolled-up magazine or a can of spray. But before you squash it, pause for a moment. Should you actually kill a false widow spider, or is there a better way to handle the situation?

The short answer is no, you do not need to kill them. False widow spiders are timid, reclusive predators that generally prefer to stay out of your way. They are actually working for you by munching on household pests like flies, mosquitoes, and gnats. Unless one has set up camp right where you are bound to accidentally squeeze it, such as inside a work glove or a pair of shoes, leaving them alone or simply moving them outside is usually the smartest approach.

People often panic because false widows share the same family tree as true black widows. They both have rounded, globular abdomens and spin messy, tangled webs in dark corners. Because of this familial resemblance, they pick up a terrifying reputation in the media. Yet, their venom is far less potent than that of their famous relatives, and they are not aggressive hunters looking to pick a fight. They only bite in self-defense when trapped directly against human skin.

Figuring out what you are looking at usually requires a quick glance at the spider underside. If you are dealing with a true black widow, the female will typically sport a bright red or orange hourglass mark on her belly. False widows, particularly the common cupboard spider, are uniformly dark brown to shiny black and completely lack those warning red markings. They do have a similar round silhouette, but that missing hourglass is your biggest clue.

If you happen to have a magnifying glass handy, you can look closer at the body shape. The front section of a false widow features a straight posterior border that forms a distinct letter D shape when viewed from above. Their webs are also a dead giveaway. Instead of the neat, symmetrical orb webs you see in gardens, false widows spin loose, messy, chaotic tangles in dark, low-traffic areas like basements, sheds, and ceiling corners.

Keep in mind that you usually cannot identify a spider from a bite mark or a skin sore alone. Unexplained skin lesions are overwhelmingly caused by bacterial infections, viral conditions, or minor burns, rather than spider bites. Unless you actually catch the spider in the act and examine it, pinning a random red bump on a false widow is usually a false accusation.

Once you have figured out what is living in your space, you have a straightforward choice to make based on the exact location. If the spider is keeping to itself in a forgotten corner of the garage or behind an old stack of firewood, you can generally let it stay put. But if it has decided to set up housekeeping in a child bedroom, an active laundry room, or right inside a shoe rack, it is time for a bit of relocation.

Forget about stocking up on heavy chemical sprays, which tend to be messy and inefficient against a lone wandering spider. A basic glass and a piece of stiff cardboard will do the trick nicely. Just trap the spider under the glass, slide the cardboard underneath, and walk it outside to the far edge of the yard. You can also grab a broom to clear away any old webs and egg sacs hiding around exterior window sills and eaves.

To stop them from crawling indoors as the weather cools down, focus on sealing up the house. Run a bead of caulk around exterior gaps near utility pipes, clear out cardboard clutter from the basement floor, and give your stored winter gear a good shake before sliding your feet inside. When you are digging through the woodpile or sorting through boxes in the attic, pulling on a pair of work gloves is usually all it takes to keep yourself safe.

True false widow bites are genuinely uncommon and usually amount to little more than a dull ache and some local redness, but you should still know when things cross a line. Roughly a third of confirmed bites bring on mild body-wide symptoms like minor muscle fatigue or a wave of nausea. If a bite leaves you with severe, spreading pain, intense cramping, dizziness, or any sign of a serious allergic reaction such as trouble breathing, get yourself to a doctor without delay.

For basic first aid, wash the area well with soap and water, slap a cold pack on the spot to keep the swelling down, and keep the limb propped up. Leave old wives' tales alone and never try cutting the skin or sucking out venom. If you strongly suspect a true black widow got you instead of a false one, head straight to the emergency room and bring the spider along in a jar if you managed to catch it safely. You can also reach America Poison Centers at 1-800-222-1222 at any hour for immediate advice.

When a heavy infestation takes over hidden spaces like crawl spaces or deep basements and basic cleaning just is not cutting it, call in a licensed pest control professional. They know how to apply approved treatments safely and strictly by the product label, solving the problem without you needing to guess at chemicals.