Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Natural area forests in US cities: opportunities and challenges.

Abstract

Not all urban greenspace is the same. Natural area forests can provision more benefits than designed landscapes, and healthy natural area forests can provide more benefits than degraded and invaded forests. Yet there is little information about the scale of natural areas in cities and their management systems. We used data sets on city parkland from across the United States and surveyed practitioners to understand urban natural area forest extent and management. We find that urban natural areas are a dominant greenspace landcover, accounting for 68% of total city parkland across 96 of the most populous cities in the United States in 2019. In the same cities over a five-year period (2014-2019), natural area parkland decreased by 4% (15,264 hectares). At municipal scales, most cities are managing forested natural areas to conserve native species. Across the 108 organizations and 92 cities that responded to our online survey, many different management interventions are being used to steer forest structure and composition. These activities and their outcomes are being tracked nearly 70% of the time by the managing organizations, suggesting a strong data basis for adaptive management. However, challenges exist: 94% of organizations cite invasive species and limited funding as primary challenges. Lack of data and low public awareness of the value of natural areas are also considered primary challenges by more than 70% of the organizations surveyed. As cities embark on efforts to expand and improve greenspace, protecting natural area parkland from development and addressing the challenges managers of these ecosystems face are two very important goals.