Vacant land, a product of population and economic decline, has increased substantially in shrinking cities around the world. In Cleveland, Ohio, vacant lots are minimally managed, concentrated within low-income neighborhoods, and support a large portion of the urban forest. The composition, structure, and value of the forest on this property type remains largely unknown, as do differences between it and forests found on lots containing standing residential structures. Abundance, taxonomic richness, taxonomic diversity, and size class of native and exotic tree species on inner-city vacant lots, inner-city residential lots, and suburban residential lots were quantified, and i-Tree Eco was used to model the quantity and economic value of regulating ecosystem services provided by their respective forest assemblages.
Inner-city vacant lots supported three times as many trees, more exotic than native trees, and greater tree diversity than inner-city and suburban residential lots, with the plurality of trees being naturally-regenerated saplings. The urban forest on inner-city vacant lots also had two times as much leaf area and leaf biomass, and more tree canopy cover. The quantity and monetary value of regulating ecosystem services provided by the urban forest was greatest on inner-city vacant lots, with exotic species contributing most of that value, while native taxa provided more monetary value on residential lots. The predominately naturally-regenerated, minimally managed exotic tree species on vacant land provide valuable ecosystem services to the inner-city neighborhoods of Cleveland, OH.