Winter isn’t the ideal season for pruning trees in Upstate New York, but it’s the best time to cut scion or twigs from ash trees in parts of the state where the species has been all but wiped out.

Picture this: You’re walking along White Rock Creek, surrounded by the dense canopy of green. In that canopy, you see the majestic ash trees. One day, a tree gets removed. Maybe you don’t notice. Then ...