Wood - Colors and Kinds
A key element in any business transaction involving wood is the proper identification of species. Literally scores of different woods are bought and sold daily for hundreds of uses. A New England home may be framed with Douglas-fir from Oregon, floored with red oak from Arkansas, sided with California redwood, and trimmed inside with Michigan yellow birch. Its furniture may be veneered with Pennsylvania black cherry over Wisconsin basswood and fitted with drawers of Indiana sycamore and backs of Carolina sweetgum. It is apparent that familiarity with only locally grown species is not enough in today’s lumber markets.
Often, any one of several species is suitable for a specific use. Other species, however, may be entirely unfit for that use. Of those suitable, some are better than others because they are stronger, perhaps, or more attractive, or hold paint better. Others may be superior because they are harder, shrink less, resist decay, or are more easily cut and joined. It follows, then, that correct identification is essential to insure selecting the right wood for a given job.
As the official wood identification agency of the United States Government, the Forest Products Laboratory annually receives thousands of requests for identification service from industry, other branches of the Federal Government, units of State and local governments, and the general public. This service is requested in connection with business transactions, civil lawsuits, criminal cases, building codes for homes and other structures, industrial standards, and Government purchase specifications. The Laboratory has also been called upon to identify wood from tombs of Egyptian Pharaohs, sunken pirate ships, prehistoric forests, and the beam that supports the Liberty Bell.
In the great majority of day-to-day transactions, however, wood identification is a relatively simple problem. By acquiring a little know-how, many lumbermen, dealers, builders, manufacturers, consumers, students, and home-workshop hobbyists could solve their identification problems on the spot. Consequently, this publication was prepared as an aid to those persons concerned with identifying the more common native species of wood.
Characteristics that are apparent to the naked eye and that distinguish our native woods from each other are described for each of 32 species. Because color is an important identifying characteristic of many woods, special attention has been paid to describing the natural color of a freshly cut surface of the wood.
Descriptions of species are accompanied by fullcolor illustrations showing grain pattern and other characteristics. Beginning at the top of the illustration, end-grained, edge-grained (quartersawed), and flat-grained (plainsawed) surfaces are all displayed. This is done because certain identifying characteristics show up best on each surface. The terms “edge-grained” and “flatgrained” are used in reference to softwood lumber, while quartersawed and plainsawed refer to hardwood lumber.
The manner in which it is sawed from the log will, of course, determine whether a piece of wood shows flat-grained or edge-grained patterns of annual growth rings on its wide surfaces. Lumber is manufactured in both forms.
Certain species are not distinguishable from close relatives by the wood alone, even under the microscope. Thus, for example, the wood of many different species of red oak is identical in structure and appearance even though the trees from which it comes may differ markedly in leaf, bark, and fruit. From the wood user’s standpoint, however, botanical differences in trees usually do not matter so long as their wood is consistent in properties and appearance. Where appropriate in the descriptions, differences are mentioned that distinguish a species from closely similar ones not shown. The general range of growth, properties, and common uses of each species are also given. Obviously, many other species could have been included with the 18 hardwoods and 14 softwoods described in this publication. Those chosen are the species most commonly found in retail lumber markets.
To assist the reader in getting the utmost help from this booklet, the terms used in the descriptions are defined in a glossary. These terms are in common use among wood technologists, and the features of wood to which they apply are regularly used for identification and other purposes at the Forest Products Laboratory. The common and botanical names of species conform to the official Forest Service nomenclature for trees. Cubicfoot weights of species described are averages taken at 12 percent moisture content; specific gravity is based on volume when green and weight when ovendry.
For information on botanical differences among species, such as the shape of leaves, patterns of bark, and form of fruit, the reader is referred to Trees, the 1949 Yearbook of the U. S. Department of Agriculture.
This work was originally published by the USDA Forest Service in October 1956, titled Agricultural Handbook No. 101, and is in the public domain. It is reproduced here with permission.