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How to Identify Maryland Spiders
The only naturally occurring poisonous spider in Maryland is the black widow spider. The brown recluse spider has been seen in Maryland, but it is thought to have been brought to the state in peoples' belongings. We will explore common habitats, behaviors, and characteristics of both the poisonous and nonpoisonous spiders of Maryland.
Black Widow Spider
The black widow is native and common in Maryland, but it's not usually found indoors. Black widow females are much larger than the males, which they often kill and eat after mating. The female becomes mature in late summer and fall and is often observed hanging upside down in her web. In such an instance, you will be able to see the distinctive red hourglass shape on her underside. Some black widow females may have a few other small, red markings, especially on the abdomen.
If you see black and red on a spider in Maryland, stay away. There's a good chance it's a black widow. There are no other spiders in Maryland that look like this species and none quite as poisonous and dangerous to children. Here are some tips for staying safe:
- Identify the Web: If you look carefully, you'll usually be able to identify the spider's irregular webs before you see the actual spider.
- Caution When Handling Wood: If you have a wood pile outdoors, wear long sleeves and gloves when you bring wood in. Turn your wood over and check for black widows especially if you know they are in your immediate area. They are usually not aggressive, and most people are only bitten when they touch or squeeze the spider, for example, when working with wood or carrying wood in from a woodpile. If you're working outdoors where you know they are established, always wear gloves and be on the lookout.
- Act Quickly If Bitten: Black widows will only bite you if you provoke them. They prefer to run away rather than confront you. Most bites will be sharp and painful. Medical attention should be sought out at once if you think you or someone else has been bitten—be sure to communicate this to the medical professionals; they will know exactly what to do.
- Spray Spider Habitats: Household insecticides will kill black widows when they are hit directly with the spray. If you find the spiders in your area or in a shed, clean out the places where they can hide. Wear long sleeves and gloves while you do this. Spray the spiders and the areas where they are hiding with a strong, soapy solution. Be sure to spray all cracks. It's best to spray all the areas at least once a month.
- Pennyroyal as a Natural Deterrent: The herb pennyroyal acts as a natural deterrent and is helpful if you sprinkle it in spider habitats. Pennyroyal can be purchased at any health food store.
- Teach Children to Identify Black Widows: Have your children look at photos of black widows so they will know how to identify them and avoid them.
Common Black Widow Hiding Places
Water Meter Boxes
Basement Window Wells
Piles of Lumber
Underneath Yard and Porch Benches
Brown Recluse Spider
While Maryland is out of the habitat range of the brown recluse spider, they are sometimes seen in the area. It is theorized that they arrived in Maryland via transport. They may have arrived in the belongings of someone who moved from an area where they do occur. If someone is bitten by what you suspect is a brown recluse, safely catch the spider in a jar and seal it in with the lid. Take it with you and seek medical attention as soon as possible.
Wolf spiders have a leg span of about two inches. They are brown with a dark grey cross pattern on the back. Most people think that wolf spiders look furry and bulky. The species is rarely found indoors though they may enter log cabins and homes surrounded by trees. They are mildly venomous, and their bites usually only cause mild itching. Some people, however, can have an allergic reaction to the bite and should seek medical attention at the first sign of distress.
Maryland wolf spiders will come inside in the late fall when they know it's getting cold outside. They are often found in basements. I've had them run across my hand or foot without incident, but they can deliver a sharp bite. Wolf spiders are very active hunters outdoors and they eat a lot of bugs; they do not make webs. The best way to keep them out of your home is to keep bushes and vegetation cut back and away from your home. Fill any holes with expanding foam to keep them out. It is estimated that as many as 99% of all wolf spiders living outdoors are hunted down and killed by wasps.
Yellow House Spider
Yellow house spiders are about one-quarter of an inch long and have yellow-green bodies and darker coloring on the legs. These spiders move rapidly. Yellow house spiders usually enter the house in the late fall where they hide out until spring. They build white webs in confined places.
Cobweb spiders will enter a home when they are small and will try to establish themselves by building a web to catch insects. If you see their web, knock it down and smack the spider with a fly swatter if you can. If you keep your house free of spider webs, you probably won't have any problem with this species. They are not poisonous.
This is the spider that you usually see on your ceiling in the late fall. They are black and hairy and some people mistake them for black widows. Jumping spiders do not have the distinctive red hourglass shape of a black widow. As the name implies, this species moves about in jumps or short, fast runs. They can be as long as one-third of an inch and may have red or white dots on them.
Crab spiders are often seen outdoors on flowers. They are yellow, white, or reddish in color and their legs protrude from their sides making them look like a crab. They cannot survive indoors. They are also not poisonous.
- Always wear long sleeves and gloves when you carry in firewood.
- There is a product called Jungle Rain that contains pyrethrum, and you can mix it up according to the package directions and spray areas outside where Black Widow spiders may be. It is a good idea to spray down your outdoor wood pile.
- One drop of tea tree oil in a quart of water will kill spiders when it makes contact with them. Citronella oil, cinnamon oil, peppermint oil, and citrus oil will also work the same way.
- If you have a problem with spiders and spider webs in your basement or attic, mix up a solution of white vinegar and coconut oil and spray corners where spider webs and spiders reside. Mix the following ingredients as follows:
- 1 cup of white vinegar
- 1 teaspoon of coconut oil
- 1 gallon of water
If you feel you have a real infestation of Black Widows or any other spider species, you may want to call a professional pest control company.
Leave Them Be
Spiders in the right place are really beneficial. They are hunter-trappers and they literally kill tons of insects each year. If the non-poisonous spider is outdoors in an area where it is not bothering anyone, leave it alone. They help to keep the numbers of pests and insects in control.
Most spiders are shy and harmless to humans, but poisonous ones like the black widow should be avoided. Always seek medical attention if you fear you or someone else was bitten by a poisonous spider. If you can, catch the spider in a jar with a tight-fitting lid and take it with you to the emergency room for identification.