Question

Read the following statements about various species of plants and animals. Based on these statements, which one would most likely be classified as an invasive species, and not just a non-native species, in the United States?
Species A is a plant from Eurasia. It is often considered a weed by homeowners and killed by using an herbicide. This plant can be consumed in salads or as a tea and is the first food resource for bees in the spring. It does not grow uncontrollably.
Species D, native to Eurasia, has been released in various American states to combat the invasive plant, purple loosestrife. It does not affect other native plants.
Species C, a plant from Japan, was introduced as a foliage crop and to reduce soil erosion. It grows up to a foot per day, smothering low-growing plants and killing trees. It has no natural predators.
Species B is from Europe and can sting people. This species is often farmed in America for its ability to pollinate and provide honey.

Answer 1

Species C. Its history of intentional introduction for erosion control, extremely rapid growth (smothering and killing native plants and trees), and lack of natural predators are the hallmarks of an invasive species (establishes, spreads, and causes ecological harm). The others describe non-native or naturalized species that don’t show that same aggressive, ecosystem‑damaging behavior.