Invasive plant cover impacts the desirability of lands for conservation acquisition

Invasive species are of increasing concern to conservation organizations due to their ecological and economic impacts. But while many studies have addressed the economic impact of invasive species, few have placed these impacts in a conservation context. In reality invasive species are only one of many challenges facing conservation practitioners. Here we use conjoint analysis, a stated preference method of economic valuation, to determine how invasive plant cover influences the desirability of land for conservation acquisition. In a web-based survey we asked public and private land managers to make choices between hypothetical land parcels that varied in area, plant species composition, and maintenance cost. We received 285 responses from managers directly involved in the management of approximately 12 % of the area of the continental United States. Rare plant richness had the strongest marginal effect on land parcel desirability, followed by invasive plant abundance, area, and finally maintenance cost. While effect ordering was consistent between federal, state, and public managers, effect strengths differed significantly; the choices of federal managers were most sensitive to invasive plant cover. Broadly speaking, our results reframe the economic impact of invasive plants in terms of trade-offs that are relevant to conservation practitioners. They also suggest that land managers, acting as public agents, are measurably concerned about the spread of invasive plants.