The holidays are a festive time. Putting up a Christmas tree, wreath, and ornaments may be part of your tradition. But, look twice before you acquire fresh plant material for your seasonal décor this year, because there may be something lurking inside. Invasive plant pests and diseases are talented hitchhikers. They may hitch a ride on your living Christmas tree, wreath, untreated firewood, or handmade ornaments. And, they aren’t just unwelcome guests—these pests threaten local ecosystems and agriculture when introduced to new places.