What do secondary infections of Bacterial Fire Blight typically involve?

Secondary infections of Bacterial Fire Blight typically involve small twigs and may extend to whole branches. This is significant because Fire Blight is caused by the bacterium Erwinia amylovora, which can infect various parts of the plant, but the initial symptoms often appear in young, tender growth such as twigs.

As the disease progresses, if conditions are favorable, it can spread through the vascular system of the plant, affecting larger sections like branches. This characteristic spread is why infection can escalate quickly in warm, wet weather, making proper monitoring and management essential for control.

In contrast, while roots, flower petals, and leaves are important aspects of the plant's overall health, they do not specifically represent the primary targets of secondary infections for Bacterial Fire Blight, which makes the understanding of twig and branch involvement critical for effective disease management strategies.