I Kudzu is a vine imported from Japan to the US in the 1800s. By the 1930s, farmers were encouraged by the government to plant kudzu for erosion control. Now common throughout the southeastern U. S., the vine grows fast and kills native species by blanketing vegetation with leaves and choking trees by encircling them with vines. II The brown marmorated stink bug is an agricultural pest, native of mainland China and first observed in Pennsylvania in 1998. It is thought to have entered the US by stowing away on packing crates of cargo ships. Piercing mouth parts cause serious damage to apples, persimmons, peaches, cucumbers, grapes, and other crops.

III Around 1987, zebra mussels were discovered in the Great Lakes region where they became a serious nuisance. Native to the Black and Caspian Seas of Eurasia, these mollusks coat the undersides of docks and boats and clog pipes and plumbing.

What do kudzu, zebra mussels, and brown marmorated stink bugs have in common?