SAN FRANCISCO (CBS SF) — A tree that critically injured a woman when one of its large limbs fell on her Friday afternoon in a San Francisco park was pruned two years ago, a spokesman for the city’s Recreation & Parks Department said.

The 36-year-old mother suffered critical injuries when the limb fell on her at about 3 p.m. in San Francisco’s Washington Square Park, fire officials said.

Canary Island Pine Branch That Hit Woman on Bench

A 100 lb. tree limb broke off and fell 50 feet, striking a woman sitting on this bench in Washington Square Park on Friday. (CBS)

Firefighters and paramedics arrived at 3:13 p.m. to the park at Columbus Avenue and Filbert Street and treated the woman before taking her to Zuckerberg San Francisco General Hospital, fire spokesman Lt. Jonathan Baxter said.

The woman was in the park with her two small children when the estimated 100-pound branch hit her after falling roughly 50 feet or more.

The reason the limb fell is under investigation, San Francisco Recreation & Parks Department spokesman Joey Kahn said.

The Canary Island pine was assessed in 2008 and 2010 and was in good condition, Kahn said.

Canary Island pines have performed well in San Francisco parks, according to Parks Department officials.

Two years ago a private tree care company pruned and up-limbed the trees around the park’s playground where the woman was injured.

Mayor Ed Lee said in a statement that officials with the Parks Department and other city agencies will be investigating the incident.

Tree crews will be looking at the condition of the trees in Washington Square Park next week.

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