Books reviewed in this article: Root Development and Function. Ed. by P. J. Gregory, J. V. Lake and D. A. Rose Modern Methods in Plant Analysis. Volume 3. Gas Chromatography/Mass Spectrometry. Edited by H. F. Linskens and J. F. Jackson Genetic Differentiation and Dispersal in Plants. Edited by P. Jacquard, G. Heim and J. Antonovics Tropical Forest and its Environment. By K. A. Longman and J. Jenik Ecology of Biological Invasions. Edited by R. H. Groves and J. J. Burdon Ecology of Microbial Communities: 41st Symposium of The Society for General Microbiology. Ed. by M. Fletcher, T. R. G. Gray and J. G. Jones.