What is a primary strategy for preventing fire blight infection in apple and pear trees?

Pruning to avoid infection is a primary strategy for preventing fire blight in apple and pear trees primarily because it helps reduce the availability of infection sites and controls potential spread. Fire blight, caused by the bacterium Erwinia amylovora, typically infects trees through open wounds, often made during the growing season by poor pruning techniques or environmental factors. By strategically pruning trees to minimize the risk of infection, such as removing branches that are overly dense or damaged, growers can help ensure that air circulation is optimized and that humidity levels are lowered, thereby reducing conditions that favor the bacterium’s proliferation.

Additionally, pruning can remove any potential sources of the pathogen by cutting away affected branches before they have the chance to spread the bacteria to healthier parts of the tree. This preventative action is integral, especially during the blooming period when trees are particularly susceptible to infection.