Brown recluse spiders, also known as violin spiders or Loxosceles reclusa, are venomous spiders found mostly in the south and central United States. They get their name from the violin-shaped marking on their bodies and their reclusive, non-aggressive nature. Though bites are uncommon, they can be medically significant and causetissue necrosis in some cases.
If you suspect you have brown recluses in your home, taking proactive steps to control and prevent them is wise. Here is a comprehensive guide on identifying them, understanding the risks, and eliminating brown recluse spiders from your house humanely and effectively.
Identifying Brown Recluse Spiders
The first step is confirming you actually have brown recluses in your home. Here are the key identification features:
- Coloration – Light to medium brown body with dark brown legs. The most distinguishing feature is the dark violin/fiddle-shaped marking on the top of the body.
- Size – Adults range from 6-20 mm (0.25-0.75 inches) in body length with legs extended.
- Eyes – 6 equal sized eyes arranged in 3 pairs in a semi-circle pattern.
- Legs – Uniform brown color lacking distinct rings or markings. 8 total legs, with 3 pairs walking legs and 1 pair leg-like pedipalps near the mouth.
- Webs – They do not use webs for catching prey. May make small irregular webs in secluded areas.
- Habits – Nocturnal and prefer dark isolated areas. Move slowly and are non-aggressive.
- Geography – Found predominantly in the south-central United States.
If you find a spider matching this description in your home, it is likely a brown recluse. Collect it in a jar for identification if unsure. Their venom makes all recluses potentially dangerous, so caution is warranted.
Understanding Brown Recluse Bite Risks
While brown recluse venom can cause significant skin lesions in some cases, the vast majority of bites heal without incident. Understanding the real risks can help respond appropriately.
- Uncommon – Most recluses are non-aggressive and bites typically only occur when pressed against skin. The chances of being bitten are remote.
- Mild Reaction – Around 70-90% of bites cause only short redness, pain, and itching – similar to a bee sting. Heals fully within 2 weeks.
- Severe Reaction – In 10-30% of bites, localized tissue damage occurs 2-8 hours after the bite forming an open, ulcerated wound. Takes 6-12 weeks to heal fully.
- Systemic Reaction – Very rare. Less than 1% have body-wide symptoms like rash, fever, and blood abnormalities indicating systemic envenomation. These are medical emergencies.
- Risk Factors – Children, elderly and immunocompromised most susceptible to severe reactions. Bites on body trunk also more prone to tissue damage.
While the venom can produce severe wounds in some cases, most bites resolve without issue. Seek medical care if worried, but extreme reactions are uncommon.
Inspecting Your Home for Brown Recluses
To control brown recluse spiders effectively, you need to find where they are living. Here are key areas to inspect thoroughly:
Attics
- Check in attic corners and openings for spiders and webs.
- Look in boxes, furniture, piles of debris that make attractive harborage.
- Inspect around ductwork, pipes, and wiring where spiders travel and hide.
- Tap rafters to encourage movement so spiders emerge from hiding spots.
Closets and Basements
- Look under shelves, inside boxes and storage containers.
- Check corners, ceilings, and unfinished walls.
- Peer inside hanging clothing, shoes, and piles of stored items.
- Lift area rugs and look under furniture in basements for spiders.
Crawlspaces
- Inspect foundation walls, wood beams, pipes and debris piles.
- Look under tarps, plywood, and insulation materials.
- Check areas with rodent activity as spiders prey on mice.
- Use flashlight to illuminate all dark corners thoroughly.
Garages and Sheds
- Look under sinks, shelving, appliances and workbenches.
- Remove debris and stored items to access hard-to-reach areas.
- Check window and door frames which can harbor wandering spiders.
- Inspect around lawn equipment, boxes and tools which provide hiding spots.
Be methodical and check all areas thoroughly. Detecting where brown recluses frequent allows you to target control efforts effectively. Having another person assist is useful.
Eliminating Brown Recluse Populations
Once problem areas are identified, taking comprehensive steps to eliminate brown recluses and prevent future infestations is key. An integrated pest management (IPM) approach is best.
Remove Access to Food, Water and Shelter
- Install door sweeps, screens, and caulk cracks to prevent entry.
- Store food securely and eliminate moisture sources like leaks.
- Reduce clutter and cardboard which provide harborage.
- Seal openings around pipes and wiring penetrations.
Apply Insecticide Sprays
- Treat known spider areas and entry points with residual sprays containing ingredients like cyfluthrin, bifenthrin or deltamethrin.
- Follow label directions carefully. Use water-based sprays and avoid oil-based near heat sources.
- Repeat applications every 2-4 weeks as needed. Direct sprays into cracks and crevices.
Use Traps and Glue Boards
- Place sticky glue boards or cardboard traps where spiders travel. Check and replace frequently.
- Install insect light traps to electrocute wandering spiders at night when active.
- Place sticky barrier traps around foundation exterior to capture spiders trying to enter.
Maintain Sanitation and Perform Exclusion
- Vacuum webs, egg sacs and wandering spiders thoroughly. Dispose of bags immediately.
- Reduce humidity and ventilation issues that allow infestations to thrive.
- Seal cracks around windows, doors, pipes and wires to prevent entry.
- Trim vegetation and debris touching structure exterior. Install lights by entry points.
Hire a Pest Control Professional
For significant or difficult to control infestations, hire a licensed pest professional.
- They have training and access to stronger spider-killing products not available to consumers.
- They can treat the entire home comprehensively, rather than just room-by-room.
- Professionals know the best application methods and can reach difficult areas.
- Routinely performs follow-up visits to ensure treatments were effective.
Preventing Brown Recluse Infestations
The key to keeping brown recluses out of your home long-term is prevention. Taking proactive measures makes your home less attractive to them.
Install Exclusion Barriers
- Caulk and seal cracks in the home’s exterior where spiders may enter.
- Install weather stripping around doors and windows.
- Use door sweeps and screens in attic openings, vents, and crawlspace entries.
Reduce Clutter and Harborage Areas
- Store items in sealed plastic bins rather than cardboard boxes.
- Eliminate debris piles and stacked materials.
- Keep basements, closets and storage areas clean and dry.
Improve Lighting and Ventilation
- Install lights around entry points and improve exterior lighting.
- Fix moisture issues and roof leaks that allow humidity.
- Make sure attics and crawlspaces have proper air circulation.
Maintain Home Exterior
- Trim back vegetation touching walls or roof.
- Keep firewood and building materials away from structure.
- Seal cracks and openings around home exterior.
Consistent prevention measures make your home far less hospitable to brown recluses seeking food and shelter. Starve them out before they get established.
Non-Chemical and Natural Brown Recluse Control Options
For homeowners wanting to avoid pesticides, there are several effective non-chemical ways to control brown recluse spiders:
Diatomaceous Earth
- Sprinkle food-grade diatomaceous earth in attics, basements, and crawlspaces.
- The sharp particles abrade the waxy spider exoskeleton causing dehydration.
- Reapply after heavy rains or saturation which reduces effectiveness.
Essential Oils
- Spray or wipe diluted essential oils like peppermint, tea tree, or eucalyptus in spider areas.
- The strong odors repel spiders and may kill them directly.
- Monitor effectiveness and reapply frequently for ongoing control.
Desiccant Dusts
- Apply desiccant dusts like silica aerogel or Dri-Kill into wall voids and cracks.
- The ultra-fine particles attach to spider bodies and absorb their outer waxy coating.
- Use hand duster to reach into crevices. Avoid breathing dusts.
Natural Predators
- Promote natural spider predators like birds, lizards, centipedes and spiders by providing habitat.
- Install bat houses and bird feeders, avoid pesticide use, and incorporate native plants in landscaping.
- Natural enemies provide free biocontrol services by preying on brown recluses.
Sticky Traps
- Use homemade sticky traps like petroleum jelly coated cardboard or duct tape.
- Check traps frequently and dispose of captured spiders carefully.
- Place traps along baseboards, in corners, and where spiders travel.
Professional Brown Recluse Treatments
For challenging brown recluse infestations, professional pest control can provide a faster and more effective solution. Here are the typical services:
Inspection and Identification
- Thorough inspection to pinpoint areas of heavy infestation.
- Spider collection and identification to ensure brown recluses specifically.
- Assess conditions encouraging infestations like clutter and moisture issues.
Customized Treatment Plan
- Review inspection findings and collaborate on treatment plan.
- Recommend most effective mix of products, traps and exclusion tactics.
- Provide written plan detailing scope of work, steps to be taken, expected results and warranties.
Products and Applications
- Use commercial-grade insecticide sprays and dusts not available to homeowners.
- Treat entire home including cracks, voids, attics, basements comprehensively.
- Apply products into hard-to-reach areas using specialized equipment.
Follow-up Visits
- Return 2-3 weeks after initial service to inspect effectiveness.
- Retreat areas still showing activity.
- Continue follow-ups until infestation is eliminated.
Prevention Recommendations
- Provide tips to reduce spider entry points and habitat suitability.
- Advise on clutter reduction, moisture control, exterior maintenance.
- Ongoing prevention maximizes long term control.
Hiring a professional takes the burden off homeowners and typically produces faster spider elimination with longer lasting results. Get multiple bids and check credentials.
How to Safely Handle and Collect Brown Recluse Spiders
If attempting to capture brown recluses for identification or disposal, exercise great caution and never handle spiders directly. Here are tips for safe handling:
- Use tongs, shovel or broom to collect spiders – never hands directly.
- Wear thick gloves, eye protection, and cover exposed skin.
- Use an unbreakable jar with a tight-sealing lid to contain the spider.
- Slide stiff paper or cardboard under the contained spider for transport.
- Freeze captured spiders for 24 hours to kill humanely before disposing sealed jar.
- Wash hands and sanitize any equipment used thoroughly after.
- Seek medical care immediately if bitten. Keep the dead spider in a sealed jar for identification.
Brown recluse bites are uncommon, but their venom can potentially cause skin necrosis. Take proper safety precautions if collection is necessary. Prevention and sanitation provide safer long-term control.
FAQs About Controlling Brown Recluse Spiders
How quickly can brown recluse spiders infest a home?
Brown recluses often enter homes one at a time and gradually build populations over several months. Heavy infestations may take 6 months to a year to develop unless conditions are highly favorable. Staying vigilant for early signs like webs in undisturbed areas can allow for quicker control before populations spike.
What temperature do brown recluse spiders die at?
Brown recluses start to die when temperatures drop below 10°F (-12°C). Short exposures to freezing temperatures are not always lethal, however. Sustained freezing for at least 24 hours is recommended when using cold treatments.
Can brown recluse spiders climb smooth walls and ceilings?
Brown recluses have specialized toe pads that allow them to climb a variety of surfaces, including smooth walls, wood, cement and even glass. Installing exclusion barriers like insect screens is important since walls alone do not pose an obstacle.
Do brown recluse spiders live outside?
Brown recluses may live for short periods outdoors in piles of debris, clutter, or woodpiles right next to a structure. But harsh weather and lack of food make permanent outdoor survival difficult. Their populations center indoors where conditions are more stable.
How long can a brown recluse spider live without food or water?
Brown recluses are quite resilient to starvation and dehydration. They have been observed surviving up to 6 months without food. Limiting food sources indoors encourages them to look elsewhere, but does not lead to quick death.
Can brown recluse spiders be completely eradicated from a home?
With comprehensive treatment and ongoing prevention, brown recluse populations can be fully eliminated from a structure and reinfestation prevented. Usually 4-6 weeks of intensive treatment inside and outside the home is required for full eradication. Follow up monitoring also crucial.
Conclusion
Brown recluse spiders can be annoying and their bites medically concerning in rare worst-case scenarios. But through careful inspection, targeted treatments, and diligent prevention, they can be controlled and eliminated from your home with minimal risk. Focus on non-chemical methods like exclusion and habitat modification first. Use less toxic options like desiccant dusts and diatomaceous earth when chemical sprays are needed. With vigilance and an integrated approach, brown recluses can be safely and effectively evicted from your home permanently.