Two goats protect US national park from invasive vines

Thelma (right) and Louise are helping to rid the Indiana Dunes National Park in Porter, Indiana, the United States, of non-native plants by eating them.

Scattered throughout the fiery autumn foliage at Indiana Dunes National Park, the United States, are green patches of Asiatic bittersweet, its yellow-orange fruit soon to split open with red berries, lending a holiday look to the woods.

But this invasive plant is better suited to Little Shop Of Horrors than any Christmas story.