Brown Recluse Control

Eric Ronning

Brown Recluse Identification

Various shades of brown

Distinctive violin shape on cephalothorax (head) spiderlings may lack violin

Long, solid-colored legs

Adult size: ¼-½” not including leg span Quarter- to half dollar-sized, including legs

Six eyes in three pairs

Thin, irregular webs

Brown Recluse

Brown recluse spiders (Loxosceles reclusa), a.k.a. fiddleback or violin spiders, are common from the south-central Midwestern states down to the Gulf states. If you live outside of that area, you’ll likely never see one. If you live inside of that area, well, you’ll likely never see one. The “recluse” part of their name was not bestowed upon them on a whim. They’re extremely reclusive and only rarely seen. In short, they’re little bitches; too afraid to leave their hidey holes until they can do so under the safety of darkness. What sucks is that if you do happen to see one in the house, chances are good that you’ll see more. In human dwellings, their population numbers swell. Lucky you.

* IMPORTANT! Protect yourself before attempting to control brown recluse spiders. Wear a long- sleeved shirt tucked into a pair of long-sleeved leather gloves, a pair of thick jeans tucked into your socks and some big, tall boots.

Controlling Brown Recluse Spiders

Reduce clutter and improve storage. Because of the shelter they provide, junk piles (boxes, papers, clothes, shoes, bedding, toys, etc.) in the house, basement, attic, crawlspace, garage or outbuildings are the best friends of a brown recluse spider. If there’s something on the floor and it shouldn’t be there, pick it up, get rid of it, or store it. When storing things, use plastic totes with tight fitting lids or boxes that have had every seam sealed with packing tape. When putting them into storage, keep them several inches from the wall.

Sweep, vacuum, and do the dishes. A broom and a vacuum are indispensable tools for brown recluse spider control. Use your broom to sweep areas where brown recluses are likely to hide and build webs, such as under baseboard heaters, under counter ledges, under and behind furniture and appliances, and in corners (both low and high). Sweeping can kill brown recluse spiders, destroy their nests, and crush egg sacs. Use the hose attachment on your vacuum cleaner in the same way. Do this several times a week for the first month and once a week thereafter. Do your entire house, top to bottom, including attics, closets, basements, crawlspaces, cellars, etc. Keep dishes clean, too. Dirty dishes lure in pests that recluse spiders like to eat.

Clean up outside. Dispose of any debris, leaf, brush, or garbage piles. Remove any rocks, boards, tree stumps, logs, and anything else brown recluse spiders may be able to hide in or under. Store firewood in firewood stands/racks and keep them well away from the house. If brown recluse spiders are finding shelter in your yard, it’s only a matter of time until they and/or their babies find their way inside the house. Finally, get rid of any vegetation (mulch included) that’s up against the house. You should have at least 18 inches to two feet of perfectly clear space around the perimeter of your house. Don’t like the way it looks? Fill it in with rocks. Oh, and tear out that English ivy.

Keep them out! Exclusion is a key element of brown recluse pest control. Grab a caulking gun, pick up a couple tubes of silicon caulk, walk around your house, and seal up potential entrance sites. First, seal around all doors and windows and all electrical components (lights, outlets, etc.). Second, locate all cables, wires, and pipes that enter the home and seal any gaps between them and the structure. Next, go around your entire house and seal the area where soffit meets wall. Finally, seal around attic and crawlspace vents and make sure they’re fitted with bug screen. Inside, make sure all window screens are tight-fitting, patch any holes they might have, and install weather stripping and doorsweeps on doors.

Kill brown recluse spiders with aerosol spider spray. There are numerous pesticide aerosols available (Cy-Kick, D-Force HPX, CB-80) that kill spiders almost immediately upon contact. Use these on brown recluse spiders that you actually see and in likely harborages, such as holes or cracks in walls. Keep in mind that after you spray inside a hole, if there is a brown recluse in there, it will likely come rushing out. Don’t worry, it will die shortly thereafter; I just don’t want you to freak out if it happens. After spraying every little crack, crevice, or hole that looks like it could house a brown recluse, wait for the spray to dry and fill all the harborages with caulking, putty, etc., to make sure they're never inhabited again.

Use pesticidal dusts for brown recluse control. These are used in much the same way as spider sprays. The main difference is that you can’t rely on dusts for quick knockdown. If your dust of choice requires a separate applicator, use a hand duster to blow it into cracks, crevices, holes, and voids. Be prepared, at every new location, for a brown recluse to come darting out. After harborages have been treated, fill them with caulk, putty, or mortar so brown recluses never get back in there. Insecticidal dusts can also be used in closets, behind furniture and appliances, in window wells, above ducting, on floors and . . . well . . . pretty much anywhere. I recommend diatomaceous earth, Delta Dust, Cynoff Insecticide Dust, or Drione Dust.

Control brown recluse spiders with residual pesticides. For long-term brown recluse control, residual spray pesticides are indispensable. Most are available as wettable powders to be mixed with water in a compressed air sprayer. Spray pesticides like Cynoff WP, Cyper WP, and Demon WP kill brown recluse spiders (and many, many other pest species) on contact, and continue killing them for up to three months. Indoors, apply in basements, crawlspaces, attics, on and under baseboards, in corners, in cupboards (but not where food is stored), in window wells, and in closets. Outdoors, apply around doors and windows, around the entire perimeter of your home (about two feet up the wall and four to six feet out into the yard) and in and around outbuildings.

Brown Recluse Spider Bite Facts

The medical term for conditions resulting from brown recluse bites is loxoscelism. Brown recluse venom is cytotoxic and can, in some instances, cause tissue death, or necrosis. Most brown recluse bites, however, are dry and cause no more discomfort than any other spider bite. If you are bitten by a spider you believe to be a brown recluse, stay calm so as not to speed the spread of the venom, and try to catch it. If you’ve already smashed the little bastard into smithereens, collect the remains. Once you have the spider or spider bits in possession, get yourself to the hospital and give them to the doctor for identification.

Brown Recluse Spider Bite Stages:

At time of bite: minimal or no pain.
2-8 hours later: mild to severe pain and redness.
Between 24 and 72 hours: area becomes larger and a pus-filled blister forms in the center. Victim may develop fever, stomach cramps, nausea, vomiting, and/or malaise.
Brown recluse spider bite symptoms rarely develop beyond this point and usually take between 6 and 8 weeks to heal on their own.
Within a week: Necrosis of underlying tissue develops and the central blister pops, revealing a crater-like ulcer.

Extremely rare brown recluse spider bite symptoms: In the most severe cases, other brown recluse spider bite symptoms may include jaundice, spleen enlargement, hemolysis, and/or renal failure.

Brown recluse spider bite treatment: In most cases, a brown recluse bite will heal up on its own. If treatments are deemed necessary by a physician, victims may be treated with corticosteroids, nitroglycerine patches, or other medications, such as Dapsone. In rare cases, excision, or removal of dead tissue, followed by skin grafting is necessary.

Natural Brown Recluse Control

Shake out bedding and clothing. Most bites occur when someone puts on an article of clothing that was on the floor and a brown recluse wandered into, or in bed when a person rolls over and traps a brown recluse between their skin and the bedding. Quit leaving clothes on the floor or at least shake them out before donning them. Also, pull your bed away from the wall, keep blankets off the floor, and pull your bedding off of the bed and shake it out before getting in. Finally, don’t use bedskirts.

Kill them with cold. Before tearing into a storage box that may have brown recluse spiders inside, put the box in the freezer for 48 hours. The cold will kill brown recluse spiders like a champ.

Change outdoor lighting. You’ve seen how many insects are attracted to those outdoor lights. All those little bugs provide brown recluse spiders with an all-you-can-eat buffet. The more food you provide them, the more of them you’ll have. Remove outdoor lighting altogether or, at the very least, switch out your standard bulbs with yellow bug lights, sodium vapor lights, or LEDs.

Set out some sticky traps. Sticky traps alone will never provide you with complete brown recluse control. They will, however, help you reduce brown recluse populations and allow you to monitor progress. Place sticky traps in corners, under furniture, behind appliances (think washer and dryer), and in other dark, secluded places.