Dutch elm disease ravaged Canadian cities. Can we help trees protect themselves?

Maureen Basnicki, her car stuffed with frames swaddled in blankets and bubble wrap, finally found a good spot to park in midtown Toronto just as artist John Coburn emerged from his studio to help unload. “This one is special,” she cautioned, touching the thickest frame. Inside the deep shadow box sat a U.S. flag folded into a tight triangle, its white stars on deep blue cloth identical to those seen in a thousand movie scenes of American military funerals. Although the folded flag is a marker of death, neither of them seemed unsettled, perhaps because their whole enterprise that day...