'15-inch' worm sees resurgence in RGV, Texas

MCALLEN, Texas (ValleyCentral) — One invasive species is making a resurgence all across Texas, including right here in the Rio Grande Valley.

The hammerhead flatworm has seen a recent increase due to wetter weather and is considered very hard to kill. They are snake-like, not good for the soil, and can grow up to 15 inches.

“It's an invasive species," said Dr. Howard Garrett, who is an arborist and the radio talk show host of "The Dirt Doctor". "It's not a native worm that we have, and its favorite food just happens to be our earthworms, which are so helpful, so it's a very definite negative force in building healthy soil.”

Recently, some were found in the McAllen and Edinburg area by Andrew Nieto. In Mission, Texas, there are also reports of it.

“If you see one, you won't mistake it," said Texas Agriculture Secretary Sid Miller. "It's over a foot long, about 12-15 inches long. It's got a big, wide head on it, like a hammer. I mean, just like it says.”

The worms have been seen from Cameron County up to Mission. Experts advise ValleyCentral that eating earthworms can be toxic to humans and pets.

They usually appear after heavy rainfall and near areas with high moisture. Miller says they are not easy to get rid of.

“The thing people need to know is don't kill it, don't squish it, don't cut it up because it makes three or four more worms, asexual reproduction, tear it in half," Miller said. "Now you've got two worms.”

Garrett says these worms can regenerate if cut into pieces because they are asexual. So, the best way is to use vinegar, salt, or citrus oil on them.

“The only thing that works on them is to put them in some type of container and pick them up and, with gloves on, as some people are allergic to these beasts as well, and put them in some container and spray it," Garrett said.

He says burning them could also work, but before handling, Garrett says you should use gloves.

“They seem to have some toxicity to certain people," Garrett said. "You know, everybody has different allergies and allergic reactions, and they can give some people a pretty nasty skin rash, kind of like poison ivy or something like that.”

If you see one, experts recommend reporting it to the Texas Invasive Species Institute. You can also email them at invaders@texasinvasives.org.