In a statement, the council said it was “deeply saddened to confirm that a member of the public has tragically died following an incident in Witton Park yesterday, when a large tree branch fell”.
The authority’s chief executive Denise Park said: “Our thoughts and heartfelt condolences are with the family and friends of the person who has lost their life at this very difficult time.
“Emergency services including paramedics and the air ambulance attended the scene. Council staff also supported by cordoning off the area to ensure public safety.
“As part of precautionary safety measures, the tree involved was being felled this morning.
“Witton Park is a much-loved community space, and the safety of everyone who visits is of the utmost importance to us.
“Our thoughts remain first and foremost with the family at this very sad time.”
A Lancashire Police spokesman said the woman’s death was not being treated as suspicious and a file would be prepared for the coroner.
Livesey with Pleasington councillor Paul Marrow said: “There have been concerns about ash dieback disease and the number of dead trees in Witton Park and across the borough.
“The council needs to make regular, thorough inspections of the trees in the park to ensure they are safe.”