The Green Monster and the Carbon Engine: Pueraria montana (Kudzu) as a Climate-Amplied Invasive Species, Biogeochemical Disruptor, and Emerging Threat to North American Ecosystems

Pueraria montana var. lobata (Willd.) Maesen & S. Almeida (kudzu) represents one of the most consequential biological invasions in North American environmental history. Originally introduced at the 1876 Philadelphia Centennial Exposition and later promoted by the United States government as a soil-erosion control measure during the Dust Bowl era, kudzu has escaped its intended ecological role to become a pervasive disruptor across the southeastern United States. This review synthesises contemporary evidence demonstrating that the ongoing climate crisis is not merely a passive backdrop to kudzu's expansion but actively functions as a biological accelerant. Elevated atmospheric CO₂ concentrations enhance kudzu’s growth and water-use efficiency, while reduced winter temperatures allow for northward range expansion. Additionally, the vine’s nitrogen-fixing capacity induces soil biogeochemical transformations that produce N₂O—a greenhouse gas approximately 300 times more potent than CO₂. Annual damages are estimated to exceed $500 million USD. This paper discusses historical context, invasion ecology, biogeochemical feedbacks, eradication strategies, and emerging bioenergy valorisation pathways, concluding that kudzu epitomises a positive climate–invasion feedback loop with significant implications for global carbon accounting and ecosystem management.