THE ECOLOGICAL SURVEY on which this book is based began to be planned in 1942, and since 1945 has been mainly centred upon Oxford University's estate at Wytham Woods, where a rich series of habitats from open ground and limestone to woodland with many springs and marshes interspersed occupies a hill set in riverine surroundings. Here biological research workers from the University have accumulated a considerable body of knowledge, some of which I...