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Tree Canada, a non-profit charity that funds tree planting across the country, has donated enough pesticide to protect 40 ash trees in Lac Leamy Park in Gatineau.
The trees are in a stand that gives shade to a picnic area near the popular beach.
And the fact that it takes a National Capital Commission press conference to announce one year’s protection for 40 trees illustrates the major effort required to protect the city’s ashes. The tall hardwoods made up one-fifth of Ottawa’s and Gatineau’s tree cover before the emerald ash borer beetle arrived.
The cost varies according to the tree’s size, but Michael Rosen, president of Tree Canada, said the treatment with TreeAzin costs “a few hundred” dollars per tree on average.
Since 2009, the NCC has been injecting 200 trees a year. Tree Canada has made donations the past two years as well.
Rosen called the treatment “a Band-Aid” that protects the trees while research looks for a permanent way to attack the beetle. Accidentally imported from Asia, it has no natural enemies in North America.
In 2013 Canada approved the importation of two tiny wasps, each about a millimetre long, that feast on the ash borer. Rosen said it’s too early to know what impact these will have.
And there’s a second struggle to save trees: The NCC and others still treat elms regularly to protect against Dutch elm disease. But Mario Fournier of the NCC said it has been a bad couple of years for some Ottawa elms that had survived decades since the fungal disease arrived — until now.
“This is probably linked with the very dry summer in 2013. Since that summer we are seeing a lot of decline,” he said.
Fournier said the NCC is planting two commercial hybrids of elm called Liberty and Patriot which are bred to resist Dutch elm disease.
They won’t know how well these young elms succeed until the trunks are about 30 inches thick, he said, “but we’re crossing our fingers because it seems that where they tried it in the States, they succeed.”
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
The trees are in a stand that gives shade to a picnic area near the popular beach.
And the fact that it takes a National Capital Commission press conference to announce one year’s protection for 40 trees illustrates the major effort required to protect the city’s ashes. The tall hardwoods made up one-fifth of Ottawa’s and Gatineau’s tree cover before the emerald ash borer beetle arrived.
The cost varies according to the tree’s size, but Michael Rosen, president of Tree Canada, said the treatment with TreeAzin costs “a few hundred” dollars per tree on average.
Since 2009, the NCC has been injecting 200 trees a year. Tree Canada has made donations the past two years as well.
Rosen called the treatment “a Band-Aid” that protects the trees while research looks for a permanent way to attack the beetle. Accidentally imported from Asia, it has no natural enemies in North America.
In 2013 Canada approved the importation of two tiny wasps, each about a millimetre long, that feast on the ash borer. Rosen said it’s too early to know what impact these will have.
And there’s a second struggle to save trees: The NCC and others still treat elms regularly to protect against Dutch elm disease. But Mario Fournier of the NCC said it has been a bad couple of years for some Ottawa elms that had survived decades since the fungal disease arrived — until now.
“This is probably linked with the very dry summer in 2013. Since that summer we are seeing a lot of decline,” he said.
Fournier said the NCC is planting two commercial hybrids of elm called Liberty and Patriot which are bred to resist Dutch elm disease.
They won’t know how well these young elms succeed until the trunks are about 30 inches thick, he said, “but we’re crossing our fingers because it seems that where they tried it in the States, they succeed.”
tspears@ottawacitizen.com
twitter.com/TomSpears1
查看原文...
