Guide to Texas Grasses, and: Grasses of South Texas: A Guide to Identification and Value by Robert B. Shaw, James H. Everitt, D. Lynn Drawe, Christopher R. Little and Robert I. Lonard (review)

As is true in many of the drier parts of world, a large portion of the plant biodiversity of Texas and many of its dominant plant species are grasses, a family that unfortunately tends to daunt even experienced field biologists. Both of these books will, in different ways, help people feel more confident about identifying grasses, and are therefore welcome resources for ecologists, range managers, and anyone else identifying wild plants in Texas. They will also likely be useful in the neighboring U.S. and Mexican states.

Grasses of Texas by Shaw is a new grass flora of Texas. It replaces an outdated (1975) but otherwise excellent grass flora, The Grasses of Texas by Frank Gould, Shaw’s predecessor at Texas A&M University. This new flora contains descriptions of 668 of the 723 species of grasses (Poaceae) presently known to occur in Texas (all species minus 6 late entries and 49 ornamentals, the latter mostly bamboos). Prior knowledge of grasses is not required to use this book, but would be useful. This is not an introductory or popular treatment, although I think a dedicated amateur could use it successfully.

Despite its inclusion in the Texas A&M Nature Guides series, Grasses of Texas is not a field guide. It is a large book: 26 cm × 18 cm × 6 cm in size (~10″ × 7″ × 2.5″) and 3 kg (6.5 lb) in weight. The binding of my barely-used review copy is already showing wear, so durability is a concern. The book’s size is due in part to its high-gloss paper and the substantial white space on many pages. Species descriptions are shorter than Gould’s, focusing on characters useful for identification, and each description has a useful map showing the counties where the species has been reported. The excellent black-and-white drawings of every species are from the Flora of North America (Barkworth et al. 2003, 2007). The attractive color photographs of many species are much less helpful. Field biologists will appreciate that so many ornamental species have been included as well as every native species and every species known to be naturalized; ornamentals sometimes grow in apparently undisturbed sites, in my experience.

Not being a taxonomist or systematic biologist, I will not attempt to evaluate the correctness of the taxonomy or the accuracy of the keys. Species descriptions are grouped by genus, and genera are alphabetically ordered. There are some scattered comments about synonymy in the generic descriptions (e.g., Nasella is described as a segregate of Stipa) but the index does not contain synonyms (e.g., Stipa leucotricha is not listed), and readers will have to use the online USDA PLANTS website or other source of synonyms to find species in this book that they know under another name. As the author is a self-confessed splitter of genera (p. 67), this will likely be an annoyance for readers who are familiar with genera but not with their latest taxonomic treatments.

The species descriptions include information about the habitats in which the species are found and their uses by wildlife and livestock. Other useful information about each species (ecoregion in which it occurs, season of growth, native or introduced, etc.) is listed separately in a table before the species descriptions. Restoration ecologists will likely find the absence of information about the invasiveness of introduced species jarring. For example, two widespread non-native invasive species in Texas, Bothriochloa ischaemum (King Ranch bluestem) and Dichanthium annulatum (Kleberg bluestem), are described as occurring in pastures, roadsides, and disturbed areas. There is...