NCC won't replace most diseased ash trees it cuts until 2018 or later, report says

ottawacitizen.com
Feb. 1, 2015
By Don Butler

About 90 per cent of the trees the National Capital Commission intends to plant to replace the thousands infected by the emerald ash borer won’t be in the ground until 2018 or later, says a report released to the Citizen - a strategy a local environmental group is calling misguided.

The report, presented at an in-camera meeting of the NCC’s board of directors last September, outlines a five-year program, ending in 2017-18, for cutting down 12,374 dead or dying ash trees that pose a safety risk. That’s significantly more than the 7,500 trees NCC staff had estimated would need to be cut just nine months earlier.

Though the NCC says it will plant a new tree for every ash it cuts down - 14,680 in total, including trees felled under regular maintenance programs, according to the report - relatively few will be planted until all the cutting has ended. In fact, 13,230 of the replacement trees will be planted between 2018-19 and 2021-22.

That’s in stark contrast to the City of Ottawa’s approach. As part of its emerald ash borer strategy, the city is planting approximately two trees for every one it removes. And, wherever possible, it plants replacement trees “well before the planned removal of the infected ash tree,” David Barkley, the city’s manager of forestry services, said in an email.

“This gives the new trees time to grow before the mature infected tree is removed, thereby minimizing the impact on the neighbourhood,” he said.

The city has removed 15,678 dead or dying ash trees from municipal properties since 2009. It expects most of the remaining 60,000 ash trees on city property will have to be cut as well, Barkley said. Most are along residential streets, where aesthetic considerations loom large.

The ash trees being removed by the NCC are typically on or near rental and commercial properties, in urban parks and along pathways and parkway corridors. Most of the affected trees in the Greenbelt and Gatineau Park will be left to decay.

Graham Saul, executive director of Ecology Ottawa, said the NCC’s plan to replace most of the ash trees in later years “is just not an effective strategy.”

Not only would it leave some areas “barren for a long time,” Saul said it will make it harder for the new trees to survive when they are planted because other species of brush will have had time to establish themselves.

A staff report to the NCC board in January 2014 raised similar concerns. It said ash mortality in forested areas creates openings for invasive species that quickly move in and colonize available space, out-competing native trees, shrubs and other vegetation. “A timely new planting intervention is the key to success in these cases,” it said.

In response to Citizen questions, NCC spokesman Jean Wolff said “experience has demonstrated that planting replacement trees before removal and site cleaning operations are completed significantly increases the risk that new trees will be damaged or destroyed during the removal operations.”

He added: “Work has to proceed in sequence - identification of infested trees, removals, followed by re-planting. Our priority is currently removing infested and dying trees.”

Wolff said the NCC has done some “proactive planting” near trees identified for removal “where site conditions ensure that the replacement trees will not block access to the infested or diseased trees during removal operations and where the new trees will have sufficient room to grow.”

Last winter, the NCC cut down ash trees along North River Road and began some replanting this past fall after its landscape architecture group created a plan for the park. More planting is scheduled this year, Wolff said.

Ecology Ottawa estimates Ottawa will lose more than 20 million ash trees over the next three to five years, including about 25 per cent of all trees in the urban area. The city - which typically plants about 100,000 trees a year - is partnering with Ecology Ottawa to plant one million trees by 2017.

The city spent $1.3 million last year to offset trees lost to the emerald ash borer, which allowed it to preserve the character of established neighbourhoods by planting more trees with larger diameters.

The NCC redacted all budget numbers in the two 2014 emerald ash borer reports because of concern their release could affect bidding for future contracts.

The NCC’s emerald ash borer program is only funded through 2015-16, Wolff said. “We still have quite large numbers for removal in 2016-17 and 2017-18 and at this point, in terms of planning, this is not funded yet.”

By the numbers

20 million: Number of ash trees Ecology Ottawa estimates urban and rural Ottawa will lose to the emerald ash borer over the next three to five years

25: Percentage of Ottawa’s urban canopy that ash trees represent

12,374: Number of infected ash trees the NCC will cut down by 2017-18 under a five-year program

13,230: Number of replacement trees the NCC plans to plant between 2018 and 2021

1 million: Number of trees Ecology Ottawa, the City of Ottawa and their partners aim to plant by 2017