Coral spot fungus, also known as Nectria cinnabarina, is another common fungal disease affecting numerous trees and shrubs. You can easily identify it by the pink to orange spore masses that form and infect weakened or injured plants, mostly attacking branches. Gardeners and arborists must understand what signs to look out for to manage and minimize the phytotoxic effects of Coral Spot Fungus on plant species, as I am about to explain.

What is Coral Spot Fungus?

Coral Spot Fungus (Nectria cinnabarina) is a fungal disease that infects most types of deciduous trees and shrubs, including fruit bushes. It gets its common form from the typical coral-pink spore masses produced on infected wood. This pathogen prefers plants that are weak or stressed, and infection is associated with branch dieback (twigs).

The fungus enters wounds or natural openings in the bark, slowly expanding and killing infected portions. Regular identification and immediate management are needed to stop the spread of Coral Spot Fungus, ensuring control over the health of our plants.

We also have a article White Rust Fungus.

Symptoms of Coral Spot Fungus

Coral spot fungus (Nectria cinnabarina) exhibits specific symptoms include that can help you identify and manage the disease:

• Bark Discoloration: Small, round spore masses develop on the bark of branches and stems. They are coral-pink to bright orange. The spore masses are typically 1-2 mm in diameter and become more evident under moist conditions.


• Branch Dieback: Infected branches and twigs often have wilted leaves or needles that turn brown before dying. It mostly affects plantations, starting at the tips of branches (dieback) and moving back down.


• Sunken Lesions: The diseased areas often form sunken cankers. These lesions can colonize woody tissue around branches, affecting nutrient and water transport, which causes more dieback.


• Brittle Wood: The wood of infected branches becomes brittle and easier to break. This fragility results from fungi that attack and break down wood fibers.


• Leaf Symptoms: Rarely, plants show symptoms of premature yellowing and shedding, especially in severe infections.


• Reduced Vigor: Previously infected plants may display a decline in overall vigor, stunted growth, and increased susceptibility to other diseases and pests.

Early recognition of symptoms can help with intervention strategies such as pruning, deadwood removal, and maintaining plant vigor if it is a good candidate for prolonged survival. Options often focus on improving plant health and sanitation practices in the garden or landscape.

Control of Coral Spot Fungus

Treating Coral Spot Fungus involves using cultural practices, sanitation measures, and appropriate care to reduce the severity and spread of the disease. Read below to learn some control strategies:

• Pruning and Removal: Periodically check plants for infection. Prune and cut back to healthy tissue on affected branches and twigs. Spray pruning tools with a bleach or alcohol solution between cuts to prevent the fungus from spreading.


• Dispose of Infected Material: Dispose of all infected plant material in a trash bag and burn it to prevent spores from spreading. Do not compost infected debris, as the fungus can directly infect and begin growing on other plants from compost.


• Improving Plant Health: Keep trees and shrubs healthy through proper watering, fertilization, and mulching to help them fend off attacks from invading organisms. The healthier your plants are, the less likely they will become infected. Minimize plant wounds, as the fungus is most likely to infect your plants through damaged tissue.


• Good Sanitation Practices: Clear up debris from around plants, including fallen branches and leaves that can contain fungal spores. Soil fumigation will suppress its lifecycle and reduce the chances of surviving in the soil over winter, thereby re-infesting plants.


• Give Plants Space: Plant in well-spaced areas to provide airflow, minimize humidity, and avoid conditions favorable for fungi.


• Chemical Treatments: In extreme cases, fungicidal treatments may be warranted. Contact your local extension service or tree care professional for fungicide recommendations and application information. Always use fungicides as a last resort and follow all label instructions exactly.


• Monitoring and Early Detection: Keep an eye out for Coral Spot Fungus, especially during wet weather when it has a higher chance of spreading. If detected early, take urgent action before it rapidly affects other plants.

The only fail-safe way of controlling Coral Spot Fungus in trees and shrubs is by incorporating these measures to prevent it from happening again, ensuring that your garden will no longer suffer severe damage.