Emerald cedars damaged by car exhaust

(Question)

We have a row of emerald cedars that separates our yard from the neighbour’s parking spot. Their vehicle backs up to the cedars and their car exhaust hits the cedars for extended periods each winter day as they warm their car. The cedar that is nearest their tail pipe has significant die back. Is their a way to regenerate this dead patch of branches?

(Answer)

Thanks for your question. Unfortunately, if entire branches of your cedar have died back, and are now brown and needle-less, they will not regrow. Assuming that your neighbour will continue to idle their car in the winter – which is, in fact, limited to one minute in the city of Toronto; other cities in Ontario also have idling bylaws – and that you would like to keep your row of cedars, you may want to consider giving them some protection over the winter to minimize additional damage. A temporary fence made of wooden stakes with a few layers of burlap stapled to them can act as a physical barrier between your neighbour’s parking spot and your cedars. If possible, leave a gap between the fence and the cedars to help buffer the heat and prevent it from reaching the branches.