Agelenopsis, or American grass spiders, are so-called because they’re commonly found in grass and shrubs. They are quite small, with females being around 10 to 20 millimeters and males being slightly smaller than that.
They’re often mistaken for Wolf spiders, or even the more dangerous Hobo spiders because they can be quite similar in appearance – grass spiders have a similar color pattern on their cephalothorax or head region. They are tan in color, and have two darker lines running down on each side(though these lines aren’t quite as thick as the lines you’ll find on Wolf spiders). A distinctive pattern found on their abdomens that distinguish Grass spiders from Wolf spiders would be light chevrons, or inverted triangles. Another thing is if you find what you think is a Wolf spider near a funnel web, that may be a Grass spider as Wolf spiders live in burrows.
Unlike the Hobo and Wolf spiders that have very painful bites, the Grass spider does not possess venom poisonous or toxic to humans. In fact, their fangs are so small that they have difficulty penetrating our skin. They are very shy, and very fast – so Grass spiders rarely end up biting humans since they very quickly move out of the unsuspecting human’s way.
Grass spiders are a genus of funnel weavers, and belong to the family of Funnel Web Weavers, so-called because they build sheet-like webs with a funnel at one end. The grass spider then sits at the end of the web and waits for prey. Their web isn’t sticky, but Grass spiders make up for it with their speed in catching prey that stumble on their nest, scurrying to bite and paralyze its victim to later consume at its leisure.
Only female Grass spiders make funnel webs, while males spend their time wandering in search of females to mate with. Once they mate, they die shortly after. The females then bide their time and build their strength until they give birth in the fall, depositing their egg sacs in narrow areas such as between rocks near their nests. Sometimes the egg sacs can be found on the edge of their webs, but sometimes these eggs can be found beside their dried up mother, whose arms may still be clinging to her yet to hatch children.
When they do hatch in the spring, they will build their own nests spread away from one another, nests that will increase in size as the spider grows. These webs are most visible after a rain, when raindrops still cling to the silk and reflect light. Try spotting one in your own backyard. While they are commonly found among blades of grass, they can also be found on weeds, shrubs, ground covers, bushes, and brush piles to name a few.While they prefer the outdoors, you may find them seeking shelter indoors (and in your own home) in autumn when temperatures drop.
Grass spiders are considered beneficial since they are quite harmless to humans and feed on pests found in our homes – but if you do find yourself infested, don’t hesitate to reach out to a pest control company for assistance in dealing with Grass spiders and other pests.