The mysterious bumps up and down your arm are likely from one of two painful pests. Knowing which is which can help you prevent them from taking over your yard.

This spring has proven to be especially annoying. The perfect storm of conditions has led to a bumper crop of pinecones to clean up, invasive trees taking over the law, painful gnat bites and destructive poisonous caterpillars.

I met several people this weekend who were still nursing battle scars from doing yard work. Painful, itchy red lumps have been appearing on necks, arms and legs all over the Hudson Valley. While everyone can agree that they're sick of these mysterious bites, no one can seem to agree as to where they are coming from.


Gnats and Caterpillars Invade New York State

This year there has been an increase in reports of ghost bugs and spongy moths. The ghost bugs are tiny black gnats that swarm in wooded and grassy areas of the Hudson Valley. Spongy moths begin their lives as tiny black caterpillars that appear to fly as they float from their nests on invisible strands of silk to search for a place to transform into adult moths.

Why Caterpillars and Gnats are Attacking New York Homeowners

Gnats and caterpillars don't have a grudge against humans. While their bites and stings are terribly painful, it's nothing personal. Both of these pests are currently in attack mode as they fight to survive and expand their populations in your backyard.

Those tiny black gnats are called no-see-ums because by the time you notice them you've already been bitten. Female gnats bite you for the same reason mosquitoes do. Your warm blood is necessary for the gnats to make eggs and reproduce. Once bitten, allergic victims develop a huge and painful red bump that itches for days.

The spongy moth caterpillar doesn't bite, but its hairs contain a histamine that can cause an allergic reaction in humans that are similar to the gnat bites. Some homeowners attempt to squish and kill the caterpillars in an attempt to save their trees, this can cause even more allergic reactions.


Is it a Caterpillar Sting or a Gnat Bite?

It may not seem to matter if you've been stung by a tiny caterpillar or bitten by a gnat, but identifying that bite may help determine which pest is invading your yard and how best to deal with it.

The most sure way of determining which insect you've been bit or stung by is to pay close attention while outside. If you see tiny black insects darting to and from and swirling around your head and later have bites, it's most likely gnats. If you've noticed small black bugs floating through the sky, most likely you're the victim of spongy moth caterpillars.

While the symptoms for both are similar, the gnat bites start with a small puncture that quickly becomes itchy.  As you itch the spot, you are actually spreading the poison and making things worse. Within hours the bite will become a red painful bump. In especially allergic individuals, the bump could be substantial in size and last for several days.

Caterpillar stings usually result in more of a rash than a bite, although a red welt could appear on the site of contact. The sensation is more burning in nature than a gnat bite, but can be just as itchy.

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The best way to tell if you've been stung by a caterpillar or bitten by a gnat is how long the symptoms continue. Generally, caterpillar stings only last for 24 hours or so. Gnat bites can take several days up to a week to completely heal.


How to Prevent Bites and Stings

Experts suggest using a bug repellant containing DEET when going outdoors in areas that are infested with caterpillars and gnats. The spray will do a good job of keeping both critters from approaching you, however a floating caterpillar doesn't have much control over where it lands.

READ MORE: 5 Sure-Fire Ways to Stop Gnats and Caterpillars From Biting

The good news is that if you are bitten or stung, the symptoms are only temporary and victims completely recover after a few days.

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