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One of the most distinguishing features of the Northend of Sydney is the lush canopy that hangs fifty feet in the air, offering joggers and dog walkers up and down George Street shady afternoon outings. But after last week’s wind that toppled some of these leviathans, it’s becoming more and more evident that our elms are not as strong as they used to be. Thanks to Dutch Elm Disease, the end of this canopy looms large. After a recent assessment of the mighty elm lining our streets, it was determined that 95% have been impacted by the disease.

The first symptom of infection is usually leaves on upper branches starting to yellow and wither in summer, months before the normal leaf shedding. This then spreads to the rest of the tree. The roots, starved of nutrients because of the withering leaves, eventually die.

A program called Dutch Trig was implemented last year in the hopes of inoculating affected tress and preventing the further spread of the disease. Alan Clark, CBRM Public Works, noted that the program began last year with 100 trees. One hundred and fifty will be inoculated this year and another 100 next year. While relatively effective, the costs of this program begin to add up given that each tree inoculated in year one must then be inoculated again in all subsequent years in addition to any new trees added to the inoculation program. The arborist who has performed the treatment to date assessed the trees that were treated last year and this past June, and reported that the treatments seem to be working.

In addition, the treatments are only available to trees with minimal exposure to the disease. Ideal candidates for treatment have 8 to 10 of leaves and roots infected. Once 15% of a tree is infected, it can not be saved, which is where the chainsaws come in.

Each year, every tree is assessed to determine its condition. If it is deemed to be significantly infected, and a hazard to the public, it is taken down. Clark says removing these century old trees is always a last resort. In some cases, such the corner of Pleasant and George, the stump and roots are removed as well to prevent further spread to neighboring trees through the root system, as is common. A brown piece of earth is now the only reminder of the massive elm that once stood on the boulevard with a painted red door, and fairies playing at its base. It is because of this mode of transmission and the short distance that these trees are from one another, that Dutch Elm Disease was able to spread and thrive in the North End.

Whenever trees are taken down, new ones are planted, but not at a 1:1 ratio. To keep a safe distance between the next generation of Northend trees, one will be planted for every couple of those that are felled. Japanese Maple and Flowering Crab, impervious to the disease and bearing colourful leaves, are slated to fill the gaps.

One of the most distinguishing features of the Northend of Sydney is the lush canopy that hangs fifty feet in the air, offering joggers and dog walkers up and down George Street shady afternoon outings. But after last week’s wind that toppled some of these leviathans, it’s becoming more and more evident that our elms are not as strong as they used to be. Thanks to Dutch Elm Disease, the end of this canopy looms large. After a recent assessment of the mighty elm lining our streets, it was determined that 95% have been impacted by the disease.

The first symptom of infection is usually leaves on upper branches starting to yellow and wither in summer, months before the normal leaf shedding. This then spreads to the rest of the tree. The roots, starved of nutrients because of the withering leaves, eventually die.

A program called Dutch Trig was implemented last year in the hopes of inoculating affected tress and preventing the further spread of the disease. Alan Clark, CBRM Public Works, noted that the program began last year with 100 trees. One hundred and fifty will be inoculated this year and another 100 next year. While relatively effective, the costs of this program begin to add up given that each tree inoculated in year one must then be inoculated again in all subsequent years in addition to any new trees added to the inoculation program. The arborist who has performed the treatment to date assessed the trees that were treated last year and this past June, and reported that the treatments seem to be working.

In addition, the treatments are only available to trees with minimal exposure to the disease. Ideal candidates for treatment have 8 to 10 of leaves and roots infected. Once 15% of a tree is infected, it can not be saved, which is where the chainsaws come in.

Each year, every tree is assessed to determine its condition. If it is deemed to be significantly infected, and a hazard to the public, it is taken down. Clark says removing these century old trees is always a last resort. In some cases, such the corner of Pleasant and George, the stump and roots are removed as well to prevent further spread to neighboring trees through the root system, as is common. A brown piece of earth is now the only reminder of the massive elm that once stood on the boulevard with a painted red door, and fairies playing at its base. It is because of this mode of transmission and the short distance that these trees are from one another, that Dutch Elm Disease was able to spread and thrive in the North End.

Whenever trees are taken down, new ones are planted, but not at a 1:1 ratio. To keep a safe distance between the next generation of Northend trees, one will be planted for every couple of those that are felled. Japanese Maple and Flowering Crab, impervious to the disease and bearing colourful leaves, are slated to fill the gaps.

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