Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Leslie Roger Landrum is an American botanist, currently serving as Senior Research Scientist at Arizona State University School of Life Sciences, and curator of the ASU Vascular Plant Herbarium. He attained M.S. and Ph.D. degrees from the University of Michigan, and has been at Arizona State University since 1986. From 1969 to 1973, he worked with the Peace Corps at the Forestry School of the University of Chile, where he gained an interest in the flora of South America, particularly the myrtle family (Myrtaceae). Since then, he has published descriptions of new genera and species within the South American Myrtaceae, devoting particular study to the genus Psidium (which includes the commercially important guava). Other concentrations include the Chilean species of the widespread genus Berberis, the usage of computer models in evaluating methods of phylogenetic analysis, and serving on a committee of botanists (including D.J. Pinkava) working on a new manual of the vascular plants of Arizona to replace the aging Arizona Flora by Kearney and Peebles (last updated in 1960).