Spiders do not generally establish extensive infestations within houses and buildings, but a few species are known for congregating in certain areas within homes. Since Arizona is home to the medically significant western black widow species, as well as five recluse spider species, not including the brown recluse, it is important for residents to identify the species of any spider/s that makes repeated appearances indoors. The relative abundance of vegetation, especially overgrown vegetation, surrounding homes is, perhaps, the most significant factor that can influence spider pest infestations within homes.
Spiders are attracted to residential yards due to the prevalence of their insect prey in gardens and lawn-grass. Some spiders capture insect prey with webs, while others have adapted to hunting down spiders on foot. Web-spinning spiders that are frequently found around and within homes include orb weavers, funnel weavers, cobweb spiders, house spiders, and black widows. Hunting spiders that are commonly found around homes include wolf spiders, crab spiders, wandering spiders, ground spiders and tarantulas. Web spinning spiders attach their silken webs to garden plants, tall overgrown weeds, shrubs and other forms of vegetation, while hunting spiders maintain a presence in yards and around gardens due to the abundance of insect food sources in vegetation-rich areas.
Spiders of all kinds are constantly present within all yards, and even in homes, but they become particularly numerous in yards where an abundance of vegetation indicates a high population of insect food sources. When vegetation becomes abundant around a home’s foundation, spiders often find a way indoors through cracks, crevices, crawl spaces, vents and a variety of other external entry points. This is why keeping shrubs and other forms of vegetation around a home’s foundation neatly trimmed will help to prevent spiders from wandering indoors.
Garden beds should be located about a foot away from a home’s foundation, and firewood should never be stacked against a home’s exterior walls. Outdoor lighting attracts insect pests, which in turn, attracts spider pests to homes, but using yellow incandescent and sodium vapor lamps in place of white incandescent and mercury vapor lamps will help to reduce both insect and spider population numbers on a property.
Have you had success at reducing arthropod pests around your home with yellow light bulbs?