Title: Liverworts and Hornworts of Southern Michigan, by Howard Crum [Review]
Abstract:This book provides a wealth of information about our nationally rare plants, in a very concise format.A series of introductory sections deal with reasons and causes of rarity, inclusion criteria, and ...This book provides a wealth of information about our nationally rare plants, in a very concise format.A series of introductory sections deal with reasons and causes of rarity, inclusion criteria, and explanations of The Nature Conservancy (TNC) ranking system and a novel Canadian priority rating scheme (intended to direct future efforts for the preparation of status reports and other conservation initiatives).The bulk of the book is composed of the species list.Each species is listed in alphabetical order, along with common synonyms, references, rankings (TNC, COSEWIC), and Canadian priority rating.TNC ranks are particularly useful, because they provide an indication of the level of rarity of each taxon in each province and territory (or District within the Northwest Territories) in which it occurs.In addition, all states in which the taxon is uncommon to rare are listed, with their TNC ranks.Thus, this book summarizes a lot of information that otherwise would have to be gleaned from numerous separate sources.Following the species list, a series of appendices provides easy cross-referencing.The appendices include a list of species by family, a list of rare endemics, alphabetical lists for each province and territory, and lists by Canadian priority category.Thus, many jurisdictional conservation program needs can be served by one or more of these readymade lists.Read More