Planted in the early 20th century to help control erosion, kudzu is a fast-growing invasive legume that fixes atmospheric nitrogen at a high rate. The Asian native is not just swallowing landscapes and altering ecosystems in the southeastern United States, the plant may also increase ozone pollution. Jonathan Hickman et al. investigated the effect of kudzu on air quality in the region by comparing nitrogen fluxes in soils invaded by kudzu to unaffected soils. In addition to environmental changes the nitrogen-fixing plants affected in other parts of the nitrogen cycle, nitric oxide emissions from kudzu-invaded soils doubled, according to the authors. Nitric oxide is a precursor to ozone, and the researchers modeled a scenario showing that the number of high ozone days in parts of the region increased by nearly 7 days as kudzu invasion climbed. Their chemical transport model showed an increase in nitric oxide of over 35% compared to a scenario without kudzu. While the scenario is extreme, the study establishes a measurable link between an invasive plant and ozone formation. In addition to its obvious visual effects on the landscape, kudzu is altering the air quality, and its range could expand as global temperatures increase, according to the authors.