New study evaluates invasive plants as food and economic resources

The spread of invasive plants across the United States has intensified efforts to eradicate established species and prevent new ones from taking hold. Yet a growing body of research and advocacy suggests an alternative approach: using invasive plants for food, medicine, and materials rather than focusing exclusively on eradication.

That idea is explored in Love Them to Death: Turning Invasive Plants into Local Economic Opportunities, a 2025 book edited by Wendy L. Applequist of the Missouri Botanical Garden. The volume argues that some invasive species are already edible, medicinal, or commercially valuable, and that controlled use could help mitigate their spread while generating local economic benefits.

The book highlights the rise of so-called “invasivores,” a term coined by journalist James Gorman to describe people who consume invasive species as a form of ecological management. The concept has gained traction through cookbooks, public events, and online initiatives promoting the consumption of invasive plants and animals.

Several invasive plants common in the eastern United States are already eaten in other cultures. Japanese knotweed, a widespread roadside and riparian weed in Pennsylvania and other states, produces young shoots that are harvested in parts of Asia as an early-season vegetable. Kudzu, a fast-growing vine expanding northward from the southeastern U.S., yields a starch that has been used in Japan for centuries as a food thickener.

Other species cited in the book include garlic mustard, whose leaves are used in sauces and pestos, and Japanese honeysuckle, whose flowers are used to flavor teas, syrups, and fermented drinks. Many plants now classified as invasive were originally introduced intentionally as food or medicinal crops by European settlers in the 17th and 18th centuries, including dandelion, plantain, and Queen Anne’s lace.

Beyond food, the book documents medicinal applications supported by varying degrees of clinical or traditional evidence. Applequist points to uses of St. John’s wort for depression, barberry for antibacterial treatments, and Japanese knotweed and honeysuckle in respiratory remedies. Other invasive species, including tree-of-heaven and autumn olive, have long histories in traditional Chinese medicine.

The authors also describe nonfood applications, such as using kudzu fibers and bamboo for building materials, invasive vines for basketry, and species such as buckthorn and knotweed for natural dyes. Several invasives, including milkweed and mulberry, can be processed into paper.

The book challenges the prevailing framing of invasive species as uniformly harmful. Applequist and other contributors argue that an exclusive focus on whether a plant is native or nonnative can obscure its ecological function. Some introduced species, they write, coexist with native plants without causing measurable damage, and the language of “invasion” can encourage aggressive control methods with unintended consequences.

Ethnobotanist Tusha Yakovleva traces Japanese knotweed’s history from its deliberate introduction as livestock forage in the 19th century to its later designation as a major ecological threat. She notes that the United States now spends an estimated $21 billion annually combating invasive plants and animals, often with limited success.

Rather than pursuing eradication alone, the book cites ecologists who advocate evaluating species based on their ecological roles. From that perspective, controlled harvesting could reduce local populations while avoiding some of the environmental costs associated with chemical or mechanical removal.

The authors acknowledge significant obstacles. Regulations often restrict plant collection and transport, food-safety laws complicate commercial use of wild-harvested plants, and improper harvesting can unintentionally worsen infestations. There is also concern that profitable uses could incentivize deliberate propagation of invasive species.

Even so, the book suggests that small-scale or recreational foraging could help suppress local populations while changing public perceptions. According to Applequist, intensive harvesting that eliminates a localized infestation should be seen as a benefit rather than damage.

The broader argument is not that invasive species are desirable, but that landscapes already altered by human activity may still offer usable resources. As climate change and global trade continue to reshape ecosystems, the book contends that pragmatic approaches combining control, use, and ecological assessment may become increasingly relevant.