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Woman was killed by a falling oak branch which struck her in a conservation area outside Hamilton


Maintaining one of North America's largest urban forests is a daunting task. The Globe looks at the risks associated with the sprawling canopy, its health and what the future holds for Toronto's trees.

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🍃 Problem trees: Three types of trees creating headaches for City of Toronto staff

Ever since a falling tree branch killed Brian Sonnenburg's only child last year, the retired police officer has been haunted by questions about whether the tragedy could have been prevented.

His daughter, Kelsey Sonnenburg, was a pediatric nurse about to celebrate her 24th birthday when she was killed by a tree limb near a popular waterfall in a conservation area outside Hamilton.

"Every day I shed a tear and [wonder] what I can do to prevent this from happening to other people," Mr. Sonnenburg, a 61-year-old former Ontario Provincial Police officer, said. "Every day I live, I think of that. This could have been prevented, in my opinion."

His daughter, who loved children, the outdoors and jumping on trampolines, was hiking with friends near the base of Tiffany Falls on May 3, 2015, when a large oak branch about 30 metres above snapped off, landing on top of her. She was outside the bounds of a viewing platform in an unauthorized area, according to an official.

Kelsey Sonnenburg, who was killed last year by a falling tree branch near Hamilton.

Kelsey Sonnenburg, who was killed last year by a falling tree branch near Hamilton.

Facebook photo

"There is signage in the area that says to stay on the trails and the platform because of natural hazards as one might expect at the bottom of a cliff face," said Chris Firth-Eagland, chief administrative officer of the Hamilton Conservation Authority (HCA), which maintains the area.

However, Mr. Sonnenburg said hikers and sightseers regularly venture close to the waterfalls, a reality he believes the conservation authority should prevent by installing a safety barrier.

"The conservation authority people know that there's hundreds, thousands of people that go right under this falls to get a closer look and that's the part I have a problem with," said Mr. Sonnenburg, who still gets choked up when discussing his daughter's death.

Mr. Firth-Eagland said such a barrier isn't an option. "We can't fence off all of nature. The signage is there. The barriers are there at the lookout, but we can't prevent people from accessing areas they want to. Our properties are too large and too porous."

About six weeks before the young nurse's death, the Tiffany Falls area was the subject of a routine inspection, but the HCA did not assess the tree involved because it maintains trees only "within striking distance" of its infrastructure, including viewing platforms, trails and benches.

"We have no program for managing trees and things for where people aren't supposed to be. That's the tough part," Mr. Firth-Eagland said, adding that the authority has 11,000 acres of natural lands.

The agency inspects trees within range of its infrastructure at least annually, a protocol he said was developed based on recommendations from a coroner's inquest into the death of a 10-year-old boy killed by a falling branch at the Royal Botanical Gardens in Burlington in 2004.

The oak limb that killed Ms. Sonnenburg was partly hollow and had some rot, he said, attributing its failure to sudden branch drop, a phenomenon where by seemingly healthy trees drop limbs on calm summer days. The tree was cut down several days later.

"While it was outside our hazard inspection area, we were aware that it had become a problem tree with what had happened, so we just removed it. Prudence," Mr. Firth-Eagland said. (At the time of the incident, local media quoted a HCA official as saying the tree was healthy and was cut down out of compassion for Ms. Sonnenburg's family.)

Kelsey Sonnenburg FACEBOOK PHOTO

When she died, Ms. Sonnenburg was one day away from visiting her parents near Carleton Place, outside Ottawa, and just four days away from turning 24. Her father learned the news from two grim-faced former OPP colleagues who showed up at his door.

Instead of throwing her a birthday party, he and his wife, Nancy, found themselves planning her funeral. "I still can't believe it," he said.

More than one year later, Mr. Sonnenburg still slips and talks about his daughter in the present tense. He and his wife are in contact with her friends and travelled to Hamilton, where she lived and worked, for a hospital charity fundraiser earlier this summer. But life without their smiling, thoughtful girl is a struggle.

"It was a total shock and I still get upset and I get angry and then you can't sleep, you can't really enjoy yourself," he said. "Everywhere you go, you think about your daughter."