Residents of North Memphis, Tennessee were horrified earlier this week when they realized their neighborhoods had been invaded by millions of spiders. According to a report from the Washington Post, however, there is no need to worry; the spiders are totally harmless.

In the week leading up to Thanksgiving residents of the northern section of the Tennessee city noticed a white sheet spread out over a half-mile area of grass. The spiders had chosen this location to weave a massive web. But why here?

WMC Action News 5 tweeted a photo of the eerie web coating an entire yard, explaining that it was not, in fact, frost. They reported that there were millions of spiders throughout the neighborhood, and residents were eager to take action on the critters.

According to local resident Ida Morris, “I’ve seen about 20 on my porch in the last day. Clean this area up and spray for these spiders and make it safe. There are kids running around. A spider could bite the kids or anything.”

Despite the understandable concern about millions of spiders setting up camp on residents’ front lawns, ecologists say that there is no reason to worry. The phenomenon is called a “ballooning” event, where baby spiders take to the winds to transplant them to a new home.

According to Susan Reichart, a professor from the University of Tennessee Knoxville and former president of the American Arachnological Society, ballooning events like this are far from uncommon. She thinks that the unseasonably warm weather could be part of the explanation behind the spiders’ late-year visit to the North Memphis neighborhood.

The tiny spiders disperse as they send out a series of thin silk threads over one meter in length. Certain air currents serve as transportation routes, which often bring hundreds of thousands or even millions of spiders to the same drop-off location. The spiders have no say in where they will ultimately land, so it isn’t uncommon for massive collections to touch down suddenly.

As juvenile spiders parachute safely down to the ground, they begin their new lives at the landing zone. This explains why there is a frost-like web stretching more than a half-mile throughout North Memphis. Reichart says that the spiders were likely living in nearby fields without being noticed all summer before making their debut.

Officials have yet to identify the exact species of spider, but it is a common practice for many North American species. Despite the hazy ID, Reichart can say for sure that these spiders aren’t dangerous – an apparent lack of pincers or teeth indicate that these little spiders would be totally incapable of piercing the skin.

The spiders may even prove to be a good thing for Memphis residents. As they touch down before winter, they will begin preparing for the cold season only to emerge in the spring and feast on the bounty of mosquitos and other pesky bugs that inhabit the area.