House Spiders In Ohio: Which Ones Are Harmless, And When To Worry

Nearly every spider in an Ohio house is harmless. Ohio State University Extension counts more than 600 spider species in the state, and its workplace guidance singles out the black widow and the brown recluse as the ones that are genuinely dangerous. The one in your basement this week is almost certainly a cellar spider or a wandering male funnel weaver.

Late September is when people start noticing. The spiders were outside all summer doing useful work, and then the calendar turned. If you are seeing more of them in Canton, Green or Hartville right now, nothing has gone wrong with the house. Something changed for the spiders.

Why Do Spiders Show Up Indoors Every Fall?

Ohio State University Extension puts it in three words in its Buckeye Yard and Garden Line fall bulletin: spiders come indoors for protection, food, or love. All three are working at once in late September, and the third one explains most of the big ones on the floor.

Love does the most visible work. Ohio State University Extension describes male funnel weaver spiders going on walkabouts in the fall looking for females, and some of them saunter into houses by mistake. The large spider sprinting across the living room carpet at nine at night is usually one of those males, lost and running, and he was never interested in your house.

Food keeps the rest of them there. The same bulletin notes that spiders eat insects, so a house filling up with fall invaders presents a smorgasbord to them. Boxelder bugs, stink bugs and cluster flies arrive first, and the spiders come for the meal. A few also move in on their own account, looking for protected winter quarters through the same gaps the insects used.

Which of the three you are dealing with decides what you fix. A spider that came in hunting leaves when the hunting dries up, so sealing out fall invaders like boxelder bugs takes care of a good share of the spiders you would otherwise be sweeping up in November.

Which Spider Is This? Read The Web First

The web tells you more than the spider does, and it holds still. Each of these builds something different, and the shape is recognizable from across the room.

Are Brown Recluse Spiders Actually In Northeast Ohio?

Rarely, and the spider people bring in is almost never one. Ohio State University Extension describes the brown recluse as a rare species in Ohio, though less so in the southern counties, and adds a detail that explains a lot about Stark and Summit County sightings: brown recluse spiders are not known to survive winter outdoors in Ohio. They survive well indoors, and they get dispersed through the movement of furniture and household goods.

So the plausible way one reaches a North Canton basement is inside something that arrived from somewhere else. A box out of a storage unit, furniture bought used, a load of things from a relative's house downstate. It is not a spider that walks in under your door in September.

The identification advice is worth learning, because the violin marking everyone looks for is not reliable. Ohio State University Extension points to the eyes instead: a brown recluse has six eyes arranged in three pairs, while most spiders have eight. That is a hand lens question, not an across-the-room question, which is the honest reason most recluse identifications on the internet are wrong.

What About Black Widows In Ohio?

They are here, statewide, and they are still not a common house spider. Ohio State University Extension has reported that both the southern black widow and the northern black widow are found throughout Ohio, correcting the widespread belief that widows stop somewhere south of us.

Two corrections to the folklore are worth carrying around. First, the marking. Ohio State University Extension notes that the deep red mark on the underside of the abdomen is not always shaped like an hourglass, and may be orangish red or yellow, so the rhyme people learned as kids is not a diagnosis. Second, the habitat. Ohio State University Extension places widow webs in woodpiles, rubble piles, under stones, in hollow stumps and in rodent burrows. Read that list again with an Ohio yard in mind: the risk is not your bedroom, it is the stack of firewood, the pile of landscape block behind the garage, and the crawl space you have not looked at since spring.

That last item connects two problems. Widows nest in rodent burrows, so a property with a rodent problem tends to offer more of the sheltered, undisturbed space widows want. Clearing the clutter against the foundation does double duty.

How Worried Should I Be About Getting Bitten?

Less worried than the internet suggests, and specific about what to watch for. The CDC's National Institute for Occupational Safety and Health states plainly that spiders are usually not aggressive and that most bites happen because a spider is trapped or touched. Pulling on a boot that sat in the garage all summer, reaching blind into a box, rolling over in bed onto one: that is how people get bitten.

NIOSH describes what the two significant bites do. A black widow bite shows two puncture marks, and the venom is a neurotoxin that produces pain at the bite area which then spreads to the chest, the abdomen, or the whole body. A brown recluse bite may cause a stinging sensation with localized pain, and a small white blister usually develops at the site. In either case NIOSH advice is to seek professional medical attention. This post is not medical advice, and a suspected widow or recluse bite is a call to a doctor, not to an exterminator.

How Do You Keep Spiders Out Of The House?

You close the gaps and you take away the food. Both are exclusion work, and late September is the right week for it in Northeast Ohio, before the first cold snap moves everything toward the foundation at once. Work this list:

• Walk the caulking and seals. Ohio State University Extension says to check along windows, doors, pipes, wires, and anything that requires a hole in the house to reach the exterior: outdoor faucets, dryer vents, soffit vents, attic vents.
• Seal what you find with the right material. The same guidance calls for a good quality flexible caulk, and insulating foam sealant for the large openings that appear when old caulk lets go around a window frame or a door jamb.
• Get down to ground level. University of Kentucky Entomology adds cracks and gaps around the foundation, doors and ground level windows, which is the zone a wandering male funnel weaver crosses.
• Move the harborage off the wall. Firewood, landscape block, brush piles and stacked containers against the foundation are where widows and recluses actually live in Ohio. Get them off the wall and off bare soil.
• Take away the prey. A house that is not filling up with cluster flies and boxelder bugs is much poorer hunting, and spiders leave poor hunting.
• Clear webs when you find them. A vacuum takes the web, the egg sacs and the spider in one pass. For the live ones indoors, Ohio State University Extension favors the gentler route of ushering them back outside.

When Is It Worth Calling Somebody?

When the webs come back faster than you can knock them down, when you are finding them in rooms you use daily, or when you are dealing with a basement or crawl space you would rather not crawl through in the first place. Spiders are a symptom pest: the population indoors tracks the insect population indoors, so the work that lasts is the perimeter and the gaps, not the individual spider on the wall.

That is what a recurring plan is for. Our State Shield Essential plan runs quarterly, four visits a year timed to break egg cycles, and it covers spiders alongside ants, millipedes, centipedes, cockroaches, mice, rats, bees, wasps and seasonal invaders. If pests come back between treatments, so do we, at no cost.

Not sure what you swept up? Our pest library can help you put a name to it. We are a fourth generation family company working out of North Canton across Stark, Summit, Portage, Wayne and Tuscarawas counties. Ask for a free estimate through our request form or call 330-494-6199.