Q: Interested in learning more about what plants are invasive and why that matters?
A: Head on over to Invasive Plants by the United States National Arboretum for all the information you’ll need. Scroll down that page for a link to your state where you can find out more about invasive plants that are causing problems in your locale.
For Pennsylvania the DCNR lists many forbs/grasses as invasive.
For a plant to be invasive
it is most likely alien to the area where it’s growing, but not all alien or non-native species are considered invasive.
Invasive plants produce large numbers of plants each year in a wide variety of conditions. They spread easily and grow rampantly when there are no natural predators to reduce their numbers.
We have to be vigilant in our gardening to assure that the aliens we keep will stay in the garden because garden-escapees make up a huge proportion of the invasive plants that are causing problems.
Just last week we were considering Dame’s Rocket as a beautiful plant, but it started life in America in colonial gardens only to escape to our modern highways and byways.