Peter Wohlleben’s bestselling book claims that trees can talk to one another and have relationships and social structures. A petition started by German academics is now circulating to denounce these “fairy tales.” “Trees are very social beings,” says German forester Peter Wohlleben; “the parents, the ‘mother trees’, look after their offspring…they like to stand close together and cuddle.” They also talk to each other, have sex, form friendships and feel physical pain, he told the Canadian documentary series “Intelligent Trees.” Wohlleben’s bestselling book “The Hidden Life of Trees,” caused a stir at Britain’s Hay Festival of Literature and the Arts...