NATCHEZ — Mississippi is being invaded.

But it’s not the Russians, the Chinese or even the Canadians who are the threat.

It’s grass. Specifically, cogongrass.

Placed on the federal government’s list of noxious weeds, information from the U.S. Department of Agriculture says cogongrass is the world’s seventh worst weed.

And it’s in Adams County.

“We have got some spots we have identified with it, and hopefully it is isolated to that area,” Adams County Extension Service Director David Carter said.

The problem with cogongrass is that it can grow so thick that other plants can’t grow alongside it. Carter said that like Mississippi’s other famous invasive plant, kudzu, cogongrass moves into an area quickly.

“When you see what is going on, it has already taken over,” he said. “If you ignore this one spot, it can take over a very large area in a very short time.”

The grass doesn’t have any positive value, Carter said, and according to the USDA, the serrated edges of the grass are so rough it can cut the tongue of any livestock that eats it.

It’s also extremely flammable.

“One of the problems is it will get into pine plantations, and it gets so thick and dense that when you try to burn it, it will get so hot it can kill the trees,” Carter said.

In the early stages of growth, cogongrass looks like Johnson grass or thick foxtail grass. And that’s what the first people in Adams County who found it thought it was, Carter said.

“They had it in an area that was so thick, they wanted to know how to thin it out,” he said. “There is no thinning it out — we had to eliminate it all.”

The seeds of cogongrass are wind dispersed, but information from the USDA says that it is most often spread by contaminated mechanical equipment. It is believed to have first arrived in the United States in the 1920s on a boat from the Asian Pacific.

Carter said in Adams County cogongrass can be found on the banks of local streams and rivers near the St. Catherine Creek Wildlife Refuge, and when it is found, the Adams County Forestry Commission tries to eradicate the plant.

Cogongrass is best controlled with herbicides, Carter said.