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topography. Field plots and remote sensing are being used to determine how the disease progresses in infected forests and spreads to new areas, providing information required for rapid response and silvicultural recommendations for managing the disease. While many thousands of acres of higher el- evation native forests in Hawai'i Island are relatively healthy, native forests growing below about 3,000 feet in elevation are often altered by a diversity of invasive plant species. In such areas, where ROD has killed or is killing 'ohi'a overstory trees, non-native plants dominate the understory, reducing their watershed, conservation and cultural value. For these systems, additional effort must be directed at dealing with multiple threats. Preliminary systemic fungistatic applications to Ceratocystis-infected 'ohi'a saplings in the greenhouse show promise of preventing death from Ceratocystis. A fungistatic is distinct from a fungicide in that an infected tree is not cured of the fungus, rather fungal growth is arrested. Development of such a tool and its application will help private landowners who wish to maintain individual ohi'a trees on their land, or for landowners who wish to maintain heritage 'ohi'a trees or 'ohi'a corridors. Fungistatics likely will need to be reapplied to the same tree on a somewhat regular basis. Research is underway to un- derstand how long a single application remains effective, and the opportunities and limitations of this method. For other species and associated wilt diseases found elsewhere, a single application has been shown prevent the advancement of disease symptoms for one to two years. Metrosideros ('ohi'a) is a highly variable genus with eight named varieties of M. polymorpha and four other species of Metrosideros found on the older islands of Hawai'i. Given this genetic diversity, re- search is underway and will be expanded to determine whether or not disease resistance exists in wild populations of 'ohi'a at genotype, population, and species levels. As a precautionary action, a state- wide effort is underway to collect 'ohi'a seed from populations throughout the main Hawaiian Islands to preserve 'ohi'a's wide genetic diversity. Current status and future need of the response — In the past two years, the Hawai'i conserva- tion community has made extensive progress in understanding and addressing the ROD crisis. A multi-agency ROD Working Group ROD was established in 2015 to coordinate research, management, and outreach. The ROD Working Group has facilitated many important advances with respect to ROD, including: definitively identifying two species of Ceratocyctis as the cause of ROD; developing and implementing aerial surveillance and ground-based ROD detection methods; careful mapping of the current extent of ROD affected stands and isolated outbreaks; building a statewide ROD prevention program that reaches many thousands of Hawaii's citizens every day; providing the science needed to establish Hawai'i Department of Agriculture's quarantine rule restricting the movement of 'ohi'a ma- terial and soil out of Hawai'i Island; and identifying the potential vectors that most likely cause spread of the disease. Continued investments are required to prevent further spread of the disease across Hawai'i Island and the state. Despite considerable progress in determining the identity, pathology, distribution, and seriousness of this disease - information that forms the basis for this SRP- addition- al research is necessary before a comprehensive strategic response plan focused on management actions can be developed and implemented. This SRP focuses on knowledge gaps and laying the foundation for an adaptable strategic response plan to address critical research needs and to provide management recommendations that can be implemented immediately, or in the very near future. This document provides the basis for enhanced partner coordination and collaboration in addressing this ecological crisis, and for building a framework for effective ROD disease management and ecosystem restoration.