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The Most Dangerous Spiders in the PNW

The Pacific Northwest is filled with lush forests and greenery, which means that it’s bound to be home to many different types of critters. Many of those critters happen to be spiders, and while most aren’t harmful to humans, there are two spiders in particular that you need to steer clear of. The most dangerous spiders in the PNW are the black widow and the yellow sac spider.

Black Widows

Black widows are the most venomous spider in Washington. But despite popular belief, these spiders are not actually aggressive, and they will only attack if they feel threatened or if their web is disturbed. A black widow’s venom is 15 times stronger than that of a rattlesnake, and they can cause serious harm if you are one of the unlucky people to get bitten.

What Black Widows Look Like

Female black widows range from 6mm to 19mm long. They have a shiny body and a distinct red hourglass-shaped mark on their underside. While male black widows exist, you don’t have to worry about them because their fangs are too small to pierce human skin. Males are about half the size of females and have striped legs and an orange, white, and brown diamond-like pattern on their back.

Adult female black widows are the ones that you need to watch for since their bite can be extremely painful to a healthy adult, but fatal to children, pets, and the elderly.

Where Black Widows Live

Black widows like to make their homes in some places that humans frequent including woodpiles, inside sheds, and under benches. Black widows also often make their homes near abandoned rodent dens, on overhanging ledges, under stones, and in outbuildings. Black widows prefer dry areas and will avoid moisture.

Yellow Sac Spiders

This unassuming spider is actually poisonous. However, like the black widow, this spider will not usually bite unless it feels threatened. Yellow sac spiders are excellent climbers and they are very fast.

What Yellow Sac Spiders Look Like

Yellow sac spiders are often yellow, green, or white, with darker legs than the coloring on their bodies. They are about 1/4 inch to 1/2 inch long, though the females are larger than the males. Unlike black widows, both the male and females can bite.

There are two common species of this spider, though they look nearly identical. Cheiracanthium inclusum has a light yellow or white body while the cheiracanthium mildei is more greenish. Of the two, the mildei species is more aggressive and will sometimes bite humans for no reason.

Where Yellow Sac Spiders Live

These spiders mostly live outdoors, especially in your garden. Unlike many other types of spiders, they don’t spin a web, but they instead hide during the day in silk sacks they weave. Yellow sac spiders often only come inside once the weather gets too cold. Though during the warm months, they tend to live in woodpiles, vegetation around your home, and in your garden. In the colder months, they come inside and will often live in your clutter, cracks in your walls, attics or basements, or even on your ceilings in the corners of your rooms.

Yellow sac spiders also sometimes hide in your laundry and become trapped in your clothing or bedsheets. This is often when they will bite you as they feel threatened.

Aren’t Hobo Spiders Dangerous?

Once thought to be extremely dangerous, the hobo spider is more docile than we first thought. Though they rarely bite, their bites are less harmful than the other spiders on this list. They are not aggressive, and they will try to get away if they feel threatened. They will only bite if pressed against the skin in very rare circumstances.

What to Do if You Find Spiders in Your Home

If you find the most dangerous spiders in the PNW in your home, call Classic Pest Control and Insulation to take care of the problem for you. Never try to take care of the problem yourself, especially if you find black widows or yellow sac spiders living in or around your home. Contact us to learn more about our pest control packages.

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