Cacti of Texas and Neighboring States: A Field Guide

Introduction

Introduction This is a field guide. Its purpose is to make possible the identification of the cacti growing in the five states covered. It therefore contains a distillation of the descriptive material from my previous book, Cacti of the Southwest, published by the University of Texas Press in 1970, as well as the photographs and keys from that book. The lesser scope of this guide, together with the desire to make it small enough for handy field use, has made it necessary to leave out the wealth of historical and taxonomic information for which the earlier book was well known. Anyone interested in those aspects of the cacti should refer to it. It has proved very difficult to deal with the cacti without becoming ensnared in the taxonomic confusion which exists concerning them. It has been impossible to note here all the different names used for the various forms, yet I desire to give the reader some reference from which to start in tracing synonyms. Lyman Benson’s exhaustive treatment, The Cacti of the United States and Canada, has appeared, and since it purports to be the bible of cactology, I have included for each form any different name he has chosen. Since his taxonomic notes are usually very complete, anyone who wishes to pursue the matter further may trace out any synonyms through them. I have included references to any new opinions published since my earlier book which seem significant to me. In the United States there has long been a tendency to break down the treatment of cacti into state studies. States are artificial areas and their boundaries have nothing to do with plant distribution, but it has been impossible to ignore them. The present study, however, includes all the forms of cacti presently known to be growing in five states: Arkansas, Louisiana, New Mexico, Oklahoma, and Texas. These five states make up a unit much more logically considered, cactuswise, than any one of them individually. The cacti are listed by their recognized scientific names, immediately followed (where such exist) by all of the common names by which the cactus is known in various localities, including the Spanish and sometimes the Indian names. Spellings of these common names show the local variations found in the literature. Each entry contains a description, updated from the original one of the species, the known range of natural distribution in rather general terms, a discussion of unusual or interesting features, and a color photograph of the plant, in most cases in bloom. More detailed information can be found in my Cacti of the Southwest. A few of the photographs were made in the plant’s natural location, but in most cases this proved to be impractical. Most cacti bloom only a few days out of the year, and it was obviously impossible to be in a canyon of the Texas Big Bend on precisely the days when each cactus chose to bloom. viii introduction Much effort, therefore, has gone into the work of locating the various forms in the wild, then bringing them in and growing them in such congenial environments that they have bloomed, so that they could be pictured at the right moment. The soils and backgrounds visible in the pictures are, therefore , not usually the natural environments of the plants. In fact, the colors of these have often been chosen to contrast with and make as clearly visible as possible the spines and other characters of the cacti. This means that no conclusion about the environments of these plants can be drawn from these pictures. Unless otherwise stated, the photographs are from my own collection . Measurements given in the photograph captions are the plant body sizes of the specific plants pictured and do not, unless otherwise stated, include flowers. In most cases this size is smaller than the maximum size achieved by the species. In organizing this presentation, one of the biggest problems was the delineation of the genera. The widest possible range of opinions is held today by the different authorities in the field on the limits of the genera in the Cactaceae . It seems that the present extent of the knowledge of the cacti does not enable anyone to give as definite a list of cactus genera as can be made for many other plant groups. There are several very different systems of genera , each very logical in the light of a certain set of assumptions. The reasons for my adopting a very conservative system are set...