The Vegetation Integrity and Cost‐Effectiveness of Different Management Options for Grassy Woodlands in Urban Green Space

ABSTRACT

Urban green space is important for conserving biodiversity in urban landscapes, however, the dominant management regime in urban green space (regular mowing) has relatively low biodiversity value. We explored if direct‐seeding (scrape and sow), planting (and mulching) and passive restoration are viable alternatives to regular mowing for restoring biodiversity to grassy woodlands in urban green space. We compared the vegetation integrity of these restoration treatments with regular mowing using the Biodiversity Assessment Method (BAM) within urban green spaces in Canberra, Australia and compared the cost‐effectiveness of each treatment. Direct‐seeding (scrape and sow) provided, on average, the greatest vegetation integrity, followed by planted, regularly mowed and unmanaged sites. Although some unmanaged sites provided vegetation integrity at the lowest cost, on average direct seeding was the most cost‐effective way to provide vegetation integrity, followed by mowing and planting. We conclude that direct‐seeding (scrape and sow) is a cost‐effective alternative to regular mowing and mulching and planting for supporting biodiversity in urban grassy woodlands, however, planting may be a better option where the goal is providing a dense shrub layer (e.g., for conserving birds). Passive restoration shows promise as a cost‐effective alternative for providing vegetation integrity if it can be implemented in locations with a low cover of exotic plants. Greater use of direct seeding and passive restoration in urban green space will require strategies (e.g., cues to care) that lead to greater acceptance of heterogeneity and ‘messiness’ within urban areas.