The aesthetic has been called “grandma graffiti” — a kind of street art that uses knitting needles and yarn instead of spray cans and stencils to impose a new visual statement on a public environment. This soft subversive act often involves a good measure of humor and irony.

This week, the Farmington Valley Arts Center found itself “victimized” by studio artists gone rogue. (Or maybe they just thought those trees looked a little chilly and ought to put on a sweater.)