Why are callery pears considered invasive?
An invasive species has three main characteristics:
- They are not naturally from the area in which they’re now present
- They create economic or ecological damage
- They displace native species
Generally speaking, invasive species grow quite rapidly and thrive in many different conditions (e.g. shade, sun, dry, wet, poor soils, hillsides, disturbed areas). A large number of invasive-exotic vegetative species are heavy seed producers (or produce seed in abundance).
While invasive species may provide shelter for wildlife (e.g. bird nests) they do not provide much food – especially for birds that eat insects – because very few insects eat the leaves of invasive species.