NEWPORT BEACH — Work crews cut into a concrete median and pruned tree roots where a eucalyptus stood before if fell and killed a motorist in September, according to construction records released by the city.
On at least four separate occasions, including one project in 1994 where the city cut the Irvine Avenue median in half, workers likely incurred into the soil near the tree's roots.
Independent experts say if the ensuing space is so tight between a tree trunk and the curb, a full-grown eucalyptus may not have enough room to anchor. Also, such incursions can wound roots and expose them to disease, especially if certain precautions aren't followed. Major damage sometimes doesn't present until 15 years later.
"When you prune roots…you make these huge gaping wounds," said Donald Hodel, an environmental horticulturist with the University of California's Cooperative Extension. "That's a recipe for disaster. It's like a ticking time bomb."
Hodel added that it may take between five and 15 years to see outward signs of internal wood rot, for instance.
Newport Beach officials were unable to answer basic questions about their construction and tree procedures on Wednesday, such as if the city keeps a record of root pruning. They also did not address specific questions about the Irvine Avenue median and the tree that fell.
Spokeswoman Tara Finnigan said that records are kept in both the Municipal Operations and Public Works Departments, and that managers could not gather information in time.
But construction records released late last week show that the most recent work to the median, in 2002, involved root pruning. The documents were released in response to the Daily Pilot's California Public Records Act request.
Contractor Southland Construction of Anaheim installed colored concrete blocks and a new irrigation system between Westcliff and Dover Drives – the same stretch where about 100 trees were removed after the September 15 incident that killed Haeyoon Miller.
City officials have not released an arborist's report about why those trees were removed and why the original tree fell. In other parts of town, the arborist found that eucalyptus trees endured similar road work, and that some developed a fungal disease and were recommended for removal.
Southland Construction's work order called for pruning the roots of existing eucalyptus trees. None of the released documentation shows if the city involved an arborist at the time of construction.
Ideally, an arborist would examine a tree's pruning and road work history when deciding whether to keep or remove a tree near a construction site, according to consulting arborist Angela Liu of Los Angeles, who has been following the Irvine Avenue trees.
But some municipalities don't keep such detailed records, she said, and construction tree-safety practices lagged until recent years.
During a previous construction project, in 1994, the city installed a left-hand turning lane—the same lane in which Miller was waiting when the tree fell on her Hyundai. That project essentially chopped the median in half, from about 19 feet to 9 feet of soil.
Experts say that blue gum eucalyptus trees need much room to grow, and that a full-grown tree, like the one that fell, would need at least a 12- or 15-foot median.Also, the species' proclivity for failure – it is the fifth most common to collapse according to the International Tree Failure Database – would warrant more space than other types of trees.
"I would have recommended the removal of that tree," said Liu.