The effects of climate change are taking a toll on Christmas tree farms across Canada, with one forestry expert and the head of the Canadian Christmas Tree Association saying the sector, which is already undergoing shifts, will need to adapt further. The trees take eight to 12 years to reach market size, and young seedlings are particularly vulnerable to climate risks, said Richard Hamelin, head of the forest conservation sciences department at the University of B.C. Much of the province has experienced prolonged drought and extreme heat over the last two summers, and the seedlings have shallow root systems that don’t reach beyond the very dry layers of soil near the surface, Hamelin explained.  …Quebec, Ontario and Nova Scotia lead the country when it comes to producing Christmas trees, and Shirley Brennan, with the Canadian Christmas Trees Association. They have also been grappling with the effects of increasingly extreme, unseasonable weather.