My most vivid memory of this book, read a month or so ago, is a description of the plague that made me want to throw up. Tepper is certainly a skilled writer in evoking violence and rather horrible things, and I think this book is actually one of her better efforts. Some of her books are quite insightful and fascinating pieces of science fiction, and others are far more trashy, with villians who have no redeeming qualities.
Grass is set on another planet, the only one in the universe where plague has not struck, and the other planets would like to know why. There is a great sense of menace in this story - not only the creeping hideousness of the plague, but a great many other horrors. It's not a story to curl up and read in a comforting armchair, but one to read tensely, leant over its pages, gritting your teeth at the more vivid descriptions. While the scientific conclusion (as to lack of plague) at the end is a bit pat, this is a fun read for fans of Tepper and sci-fi in geneal.