This book is mostly about the plant communities of a very large area in south-central Texas called the Edwards Plateau where a number of plant communities come together. This area is a physiographicregion and a confluence of many divergent and discontinuous communities. Many of the plant communities in this area have never been described and nothing is published about them and I plan to rectify this. Work on the species and communities of this area are scattered throughout the literature. I plan to bring this work together in one place. Much of what has been said in the past about this large general region of Texas is hearsay or speculation and much is incorrect and will be corrected here. Communities and factors responsible for allowing the communities to develop and persist will be examined including species present, light levels, herbivory, fire frequency, availability of soil water and soil nutrients. The limits of plant species and communities in this area are difficult to understand including why a community is located where it is and what caused it to be there, how it interacts with other communities and the factors or condition that control the distribution and how the communities interact will be carefully examined and explained in light of recent research.

There are over 281 species of woody plants and 32 species of cacti in the South Texas ecological region. The vast majority of these are found in the lower Rio Grande Valley, which is part of the subtropical Tamaulipan biotic province. Many of the plant species in this area reach their northernmost boundary here. The 44 plants described in this guide represent an estimated 75% of the overall brush biomass of the South Texas ecological region, excluding the lower Rio Grande Valley. The plants are grouped into thorned and thornless categories and alphabetized by family. Distinguishing characteristics have been italicized for easy reference. Similar species are also noted. In this guide, plants are not ranked by importance because their value to animals can differ from ranch to ranch, depending on the plant's availability and the ranch's location, soil type, and land management practices. In case a plant is not found in this guide or more information is desired, a list of additional references is included.

New Dorothea L. Leonhardt Foundaton (Andrea C. Harkins), Bass Foundation, Ruth Andersson May, Mary G. Palko, Amon G. Carter Foundation, Margret M. Rimmer, Mike and Eva Sandlin.

For fifteen years, the Texas Master Naturalist program has been hugely successful, training more than 9,600 volunteers who have given almost 2.8 million hours to nature education. This dedicated corps of naturalists provides teaching, outreach, and service in their communities, promoting the appreciation and stewardship of natural resources and natural areas around the state. Hundreds of new volunteers are trained every year, and the Texas Master Naturalist Statewide Curriculum serves as the basis of instruction for trainees who complete a certification course taught under the auspices of more than forty program chapters. The curriculum contains twenty-four units of instruction that range from geology to ornithology to wetland ecology—all written by the state’s top scientists and experts. Available as well to educators, interpreters, and others who may not yet be able to commit to the Texas Master Naturalist program, the curriculum offers an authoritative source of information for anyone seeking to learn more about the natural world in Texas.

Provides a comprehensive review of the role of species interactions in the process of plant community assembly.