Late fall is the perfect time of year to look for alien plants in Pennsylvania. Natives are brown or leafless but alien species are still cuing on the seasons back home.
How do you find aliens? Notice patches of green in the brown landscape. Here are three photos to give you some practice.
Aliens in the top photo are circled below.
See aliens while you're driving ...
See aliens on the ground ...
There's so much goutweed and garlic mustard in this last photo that it would be filled with red circles if I labeled all of it. 🙁
(photos by Kate St. John)