Former doctoral student Liz Matthews, Ph.D., had documented plant species composition at the best remaining examples of forest situated near streams. By comparing urban forest sites to these reference sites, Lopez found that many rare species found in reference sites are absent from urban forests. Native species whose seeds travel only short distances are also found at lower frequencies in urban forests than in reference sites. These results suggest potential challenges for maintaining and restoring native plant biodiversity in urban areas.
Lopez has identified plant species that are highly affected by urban development and those that are resilient to this process. Her study findings indicate the need to set aside larger forest patches for conservation to encourage seed movement and buffer the effects of warmer urban temperatures. She plans to share her information with city and state officials to inform forest conservation and restoration policies.