Perennial Ground Covers is a great example of the high standards of Timber Press publishing of horticultural subjects. MacKenzie does an overall exceptional job at breaking down hundreds of species of both traditional and non-traditional groundcovers. Many of the plants included here are clever and reasonable additions to those that would normally be considered groundcovers, while some step over a few bounds, with no harm done nonetheless, to be included in this group. This reference book is best for those with just a little more than basic plant knowledge, but can be just as helpful for the beginner. It is refreshing in its approach that does not baby the reader as it does not assume they know nothing about plants at all. The breakdown of this book consists of an introduction, including an explanation on nomenclature, a section of plates of each groundcover included in the book, a non-picture section of species in alphabetical order, and an outstanding appendix of characteristics in table form for all of the plants included. One main drawback of the book is a lack of family names of species that have descriptions. This is where a grouping by relationship or by environmental conditions would be better than an alphabetical listing. I appreciate that the pictures were kept together in a separate section, rather than including them alongside each description. This makes for easier use for reference. I would recommend this book to anyone interested in a reference for both groundcovers and perennials as two individual groups of plants.

Wallace's study is a basic source for Mackenzie in Texas but is short on his life and personality in other respects. I recommend that the interested reader check out Michael D. Pierce, The Most Promising Young Officer: A Life Of Ranald S. Mackenzie (Univ. of Okla. Press, 1993) for a scholarly study of Mackenzie's life.