Field guide

A field guide is a book designed to help the reader identify wildlife (plants or animals) or other objects of natural occurrence (e.g. minerals). It is generally designed to be brought into the 'field' or local area where such objects exist to help distinguish between similar objects. Field guides are often designed to help users distinguish animals and plants that may be similar in appearance but are not necessarily closely related.

It will typically include a description of the objects covered, together with paintings or photographs and an index. More serious and scientific field identification books, including those intended for students, will probably include identification keys to assist with identification, but the publicly accessible field guide is more often a browsable picture guide organized by family, colour, shape, location or other descriptors.

Popular interests in identifying things in nature probably were strongest in bird and plant guides. Perhaps the first popular field guide to plants in the United States was the 1893 How to Know the Wildflowers by "Mrs. William Starr Dana" (Frances Theodora Parsons). In 1890, Florence Merriam published Birds Through an Opera-Glass, describing 70 common species. Focused on living birds observed in the field, the book is considered the first in the tradition of modern, illustrated bird guides. In 1902, now writing as Florence Merriam Bailey (having married the zoologist Vernon Bailey), she published Handbook of Birds of the Western United States. By contrast, the Handbook is designed as a comprehensive reference for the lab rather a portable book for the field. It was arranged by taxonomic order and had clear descriptions of species size, distribution, feeding, and nesting habits.

From this point into the 1930s, features of field guides were introduced by Chester A. Reed and others such as changing the size of the book to fit the pocket, including colour plates, and producing guides in uniform editions that covered subjects such as garden and woodland flowers, mushrooms, insects, and dogs.

In 1934, Roger Tory Peterson, using his fine skill as an artist, changed the way modern field guides approached identification. Using color plates with paintings of similar species together – and marked with arrows showing the differences – people could use his bird guide in the field to compare species quickly to make identification easier. This technique, the "Peterson Identification System", was used in most of Peterson's Field Guides from animal tracks to seashells and has been widely adopted by other publishers and authors as well.

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Wikipedia