by Dean Ruhl, Oklahoma State University Extension

Are you being a good neighbor?

It’s a question Karen Hickman, a professor of natural resource ecology and management and director of the environmental science program in the Oklahoma State University Ferguson College of Agriculture, poses while discussing invasive plant species in Oklahoma.

Some of those invasive plants can spread onto neighboring properties, meaning upkeep and removal are important. But the “Dirty Dozen,” which encompasses 13, not 12, invasive plant species widespread across the state, pose dangers to rangeland in Oklahoma beyond just upsetting neighbors.

“Typically, we care about these invasive species because of the harm to human health, harm to the economy or harm to biodiversity,” Hickman says.

Leaving the plants on your property could result in decreased forage. The plants could be toxic. The invasive species could be detrimental to wildlife habitats, decreasing populations for hunting purposes. Fire dangers can increase, too, if species are left untreated.

“We see that a lot with eastern redcedar,” Hickman says.

Of the 13 invasive species listed, one — musk thistle — lands on Oklahoma’s noxious weeds list. Scotch and Canada thistle are also considered noxious weeds in Oklahoma. That means landowners are legally required to control, treat or eradicate them. A light infestation is quantified by less than two plants per acre, a medium infestation is two to nine plants per acre, and a severe infestation is 10 or more plants per acre.

Properties on the border of other states also need to remain aware of what those states have legally defined as noxious weeds.

“There are noxious weeds that your Kansas neighbors are going to have to control, and Oklahoma landowners are not legally going to have to,” Hickman says.

Treating the problem will depend on the specific species and the growth stage, Hickman says. She stressed the importance of reaching out to your county Extension office and asking for assistance with species.