The USDA Forest Service: Northeastern Area (UNDATED) states that, "Discula destructiva Infections often progress down the petioles of blighted leaves into shoots, resulting in cankers. Direct infection of shoots, resulting in tiny cankers, may occur on C. florida during spring and fall. Girdling cankers typically develop at leaf nodes, causing twig dieback. On C. nuttallii , fall blighting of terminal leaves is common, resulting in death of terminal buds. Twig dieback is most common in the lower crown following years of extensive spring or fall leaf blighting. As a result of twig dieback, succulent shoots proliferate on the lower trunk and main branches of affected trees. These branches are very prone to infections, which may progress into the main stem Multiple cankers can girdle individual branches or kill the entire tree." The USDA Forest Service: Southern Region (UNDATED) adds that, "Cankers may not be present on all the dead trees. Larger trees often die 2 to 3 years after the first symptoms are found in the leaves." The fungal growth and virulence at 28 C and higher is significantly decreased (Ning and Blackwell, 2002).
Location Specific Impacts:
Economic/Livelihoods: In Europe, the main hosts C. florida and C. nuttalii are not naturally present in forests, but they are valuable amenity plants for parks and gardens. Therefore, D. destructiva could present a risk to the nursery industry.