While researching a topic, a student has taken the following notes:
- A nonnative species is considered invasive if it causes environmental or economic harm in an ecosystem.
- Curly pondweed is a species of aquatic plant native to parts of Eurasia.
- It can also be found in the northern and western US.
- There, it crowds out native plants and impedes aquatic recreation.
- It is considered an invasive species in the US.