July 3, 2008 · Updated 3:50 PM
An oak tree expert hired by the city of Oak Harbor to evaluate the landmark Garry oak at the post office says that chopping the tree down should be a last resort.
I think a chainsaw is very low on my list, Darlene Southworth, professor emeritus in the biology department at Southern Oregon University, told members of the citys ad hoc oak tree committee and others during a public meeting last week.
She said the stately old tree likely has a long life ahead of it. The tree is not acting sick, she said. The biggest threats to it are chainsaws and bulldozers.
Yet while Southworths evaluation makes it less likely that the tree will be cut, it doesnt yet ensure its future. Especially when there are questions of safety and liability.
After the professor completes her written report, the citys ad hoc oak committee along with the citys legal department will make a recommendation to the city council, possibly before the end of the year, about what to do with the tree. The final decision will be up to the council.
Southworth confirmed an arborists assertion that a fungus has infected the tree, but she presented a much more positive prediction for the trees future than the council had heard before. Council members previously voted to cut down the tree, but changed their minds in a last-minute, emergency meeting early this year in order to get a second opinion.
Southworth spent a couple of days investigating the tree and looking at other Garry oaks in the city. She concluded that the post office oak is doing well, even with the fungal disease. The tree doesnt grow very fast. The fungus doesnt grow grow very fast, Southworth said. The question is whether the tree can grow enough to outgrow the fungus.
She said that it probably could. She pointed out that the main indicators of health amount of leaves, number of acorns, evidence of branch die-back all point to a healthy tree. In fact, she said the tree may be older than the 300 to 350 years that other tree scientists estimated it to be, which would make it the oldest oak in the state.
Southworth was also critical of the report from the citys arborist, Robert Williams, which calls the tree a safety risk because the fungal disease may cause it to fall and maim someone. She made light of his hazard rating system, calling it capricious. She said one thing he missed was to compare the tree to others in the city, which she said would have given him a better picture of the trees health.
Also, Southworth whos studied Garry oaks for decades said shes never heard of a resistograph, which is the tool Williams used to examine the tree and largely based his evaluation on those results.
On the other hand, Southworth agreed with Williams that the city can take steps to lessen the chances of someone being injured by a falling limb. She suggested getting rid of two to four parking spots which sit under the trees canopy in the post office parking lot and on the street, and putting in more flower beds instead.
Southworth and members of the public works department dug a hole into the flower beds and found a proliferation of oak roots, which she said is a very good sign.
Southworth also said the city could make the environment as healthy as possible for the tree, which may help it outgrow the fungal problem. She said as much blacktop as possible should be pulled up from underneath it and replaced with either mulch beds, or if thats not possible, some type of pervious surface.
In addition, Southworth explained that the leaves that fall off the oak tree should be left in place and allowed the rot because they are extremely beneficial to the trees health.
In fact, Councilwoman Sheilah Crider, who has led the effort to save the tree, is calling for residents to donate oak leaves, or even the soil from around oak trees, to the city so they can be spread underneath the tree.
She hopes that Southworths investigation will lead to permanent protection of the tree.
The vast hope is that this tree will stand for another 100 years, she said, which is really very realistic.
You can reach Jessie Stensland at email@example.com or 675-6611.