Cheshire West and Chester Council has seen an increase in the number of phone calls regarding fallen tree branches even on calm, wind-free days.
The council recently advised residents of changes to its usual maintenance activities at this time of the year, due to increased leaf drop following the continuing warm weather.
This latest phenomenon is often referred to as ‘sudden branch drop’; it often happens on hot, calm days and evenings, typically in the summer during drought conditions.
Most tree specialists believe it is related to maintaining or reducing moisture levels within the tree. Trees release water into the atmosphere through their leaves, however, calm, hot conditions limit how much moisture trees can release.
One theory on sudden branch drop is that high humidity increases the moisture content within branches and eventually causes the heavy branch to fall from the tree.
The council’s cabinet member for environment, Cllr Karen Shore, said: “Trees provide shade and shelter which is beneficial the majority of the time in hot weather. However the unpredictable nature of this phenomenon increases the risk of using such areas.
“Our trees officers wanted to make residents aware of this phenomenon as thunderstorms are forecast for the coming days, and it is more likely to happen during or following rainfall.”