This week marks Invasive Species Awareness Week, and experts are breaking down the impacts of unwelcome species on ecosystems in Virginia and across the U.S.

An invasive species is a non-native plant or animal that spreads and rapidly displaces native species. Often, these are introduced through human activity and cause economic or environmental harm, or even harm to humans.

Jacob Barney, professor and director of the Invasive Species Collaborative at Virginia Tech, said this can happen accidentally or intentionally.

"So their impacts can be broad and sometimes quite profound, in some cases, resulting in the wholesale extinction of native species," said Barney. "These affect pretty much every place on the planet. We have sort of homogenized the biota of the world by moving things around."

Virginia is home to dozens of invasive species, including plants like the so-called Tree of Heaven or the Bradford pear tree. Invasive animals and insects have also spread through the Commonwealth, such as the spotted lanternfly and northern snakehead fish.

Barney explained that taking a good look at your own yard can help efforts to combat the spread of invasive species. He said one of the simplest steps a person can take is searching their property for unwelcome plants.

"Educating yourself on which species are considered problematic where you live and finding native alternatives, or non-natives that are non-invasive," said Barney. "It’s a very simple thing you can do, sort of voting with your wallet, by reducing the number of known invasive plants into the environment."

Invasive species cost the Commonwealth an estimated $1 billion annually, according to the Virginia Department of Conservation and Recreation.