"An acre of poppies and a forest of spruce boggle no one's mind. Even ten square miles of wheat gladdens the hearts of most . . . No, in the plant world, and especially among the flowering plants, fecundity is not an assault on human values. Plants are not our competitors; they are our prey and our nesting materials. We are no more distressed at their proliferation than an owl is at a population explosion among field mice . . . but in the animal world things are different, and human feelings are different . . . Fecundity is anathema only in the animal. "Acres and acres of rats" has a suitably chilling ring to it that is decidedly lacking if I say, instead, "acres and acres of tulips"."