I know Spiders are good for you and the environment, but I have a few friends that are afraid of spiders and my house is not exactly infested- but it seems that everyday, new spiders show up. The questions I have, should I keep them? How do I control them? Who are the bad spiders? What are the non-toxic, readily available products to keep spiders in line?
- It has been estimated that the number of insects eaten by spiders in that country every year exceeded the weight of the people who live in the U.K.
- 3,000 different spiders in North America, but only a few of them cause problems for people.
- The world wide benefit of pest control by predatory insects and spiders together may exceed US $100 billion per year.
Benefits of Spiders
- Control insect populations
- Reducing local disease-carrying insects, spiders
- Provide humans with other medical benefits. Spider venom is used in neurological research and may prevent permanent brain damage in stroke victims.
- Provide raw materials for new generation pesticides based on their venoms and new drugs and textiles based on venoms and spider silk.
- The silk produced by spiders is used in many optical devices including laboratory instruments.
The Black Widow Spider
Only the female Black Widow bites. She is about a half inch long, black (hence the name), and sports a red hourglass on the underside of the abdomen. There are also Brown and Red Widow spiders in various parts of the US; these only sometimes have the noticeable hourglass.
The Brown Recluse Spider
The Brown Recluse is also about a half inch long, sometimes shorter. The spiders are brown (again, the name is a giveaway) and can be identified by their violin-shaped markings beneath the thorax (middle section).
Though the Black Widow and Brown Recluse Spiders are poisonous, they are not that much of a threat in most cases. Black Widow Spiders are very reclusive, tending to gravitate toward places where people aren’t. Brown Recluse spiders are rare except in the lower Midwest in the US. The Brown Recluse also tends to stay away from people.
- Indoors, get rid of their webs. Cleaning is the best method of spider prevention, so go through your home vigorously sweeping, dusting, and vacuuming. Do this weekly for a couple of months to destroy existing nests, not giving spiders time to rebuild and lay eggs.
- Outdoors, get out the hose. Use the water to knock webs and spiders out from under the eaves. Repeat weekly or as necessary. Keep grass and weeds that grow near the house cut low, and likewise keep shrubs near the house small and neatly maintained.
- Make your home less appealing to spiders. If there are cracks in your foundation or around windows and doors, seal them up. Check places where water pipes and electrical lines enter your house, and caulk any openings. Keep woodpiles and debris away from your house. In storage areas, put boxes up off the floor and away from walls. Seal boxes with tape to keep spiders from living inside them. In general, cleaning up clutter will mean you have fewer spiders.
- Pruning vegetation away from your house and keeping the area next to the foundation clear will also make your house less attractive to spiders. Outdoor lighting sometimes attracts insects, which in turn attracts spiders. You can move outdoor lighting away from windows and doors if this is a problem around your home.1
Chemicals Are Ineffective
- Using a pesticide is not a good solution to spider problems. “Insecticides will not provide long-term control” of spiders, according to the University of California, “and should not generally be used against spiders outdoors.” Inside, “control by spraying is only temporary unless accompanied by housekeeping.” Washington State University Extension has a similar perspective: “Most spider problems can be solved without the use of chemicals.”
All of the above is well and good- but being pro-active, (and wanting my friends to visit) what else can I do?
Here are some ideas from other people for Natural Spider Prevention (except for the Lemon Pledge one)
- Remove spider webs is to take used dryer sheets and attach them to the end of a broom handle. Wave the broom handle like a wand to sweep away all the spider webs.
- Put chestnuts around the exterior walls of every room in the house as well as on all the windowsills. Friends, who live in the city and share a balcony with a neighboring apartment, put chestnuts under the sliding door to their balcony. They have had no spiders while their neighbors continued to be infested. I’ve read a couple of newspaper articles about the use of chestnuts to repel spiders, too.
- Get a package of pipe or chewing tobacco, soak it in a gallon of boiling water until it cools. Strain the liquid into a clean container. Put a cup of tobacco juice and 1/2 cup lemon dish soap into a hose-end sprayer and spray. I.
- “I learned this from the man who trained the spiders for the movie Arachnophobia. Spiders have their taste buds on the tips of their legs. They also hate the taste of lemon pledge. Dust your windowsills and doorframes with the pledge, both inside and out, and any areas where they accumulate. The spiders will find that they don’t want to live with you.”
- “I live in Texas and have found the fruit from the bois d’arc tree or also known as osage orange tree (the fruit we call horse apples here) are a great repellant for spiders. I don’t know if you have these trees in the Midwest. But if you do, try quartering the apples and place one quarter in each corner of a room. The spiders just disappear. I used this when we moved into a house that had been unoccupied for a year and the spiders were in total residence. Within a week, they had all left! Judy
- Essential oil of Lemon is a great natural deterrent for spiders. I make my own surface cleaner for cleaning counter-tops etc. and use a few drops of lemon oil in that to keep spiders out of the kitchen area, and I put some in my mop water and the water I use when I clean walls or ceilings.
- I also make up a room spray with about two cups of distilled water, a couple drops of Seventh Generation dishwashing liquid (acts as an emulsifier to allow the lemon oil to mix with the water) and 5 to 15 drops of lemon oil depending on how lemony I want it (I occasionally mix in other essential oils as well for other properties they might have… essential oil of lavender is nice with the lemon… I never go above a total of 15 drops of oil though in one batch though). I squirt that in corners that I know spiders are attracted to and around the house.