Wood and log species ID: what the Forest Products Laboratory and extension say
Telling one wood from another by its end grain, pores, rays, colour and smell is a craft with limits. The Wood Handbook, a Michigan State key and a Mississippi State page say what the features are, what a hand lens adds and where the Forest Products Laboratory says identification stops being reliable.
Checked against the sources at the bottom of this page on October 9, 2026. Rules, fees and pay change: the source has the last word.
This page describes what the three named sources say. It does not identify any piece of wood or log, and it is not a key. For which woods are sold as firewood and how they are seasoned, the page on firewood species and seasoning sets out what extension services and Forest Research say.
How far identification can go
The Wood Handbook (Forest Products Laboratory, FPL-GTR-282, 2021) defines wood identification as recognizing characteristic cell patterns and wood features, and says it is generally accurate only to the generic level. Its reason is that woods of different species in one genus often have different properties, so mixing them causes problems in making and using wood. It says lumber graders, furniture workers, people in the industry and hobbyists often identify wood without laboratory tools, using colour, odor, grain pattern, density and hardness. Accuracy, it says, depends on the person's experience and the quality of the sample: an atypical, decayed or small piece is often identified wrongly. It reports that a 10 to 20 times hand lens greatly improves accuracy, and that some foresters and wood technologists with a hand lens and sharp knife can accurately identify lumber in the field by looking at a cut on the end-grain surface.
The same section lists the techniques researchers use besides the hand lens: computer vision, light microscopy, near-infrared and mass spectroscopy, and DNA methods. It says the best result comes from applying them together in a sensible sequence. Mississippi State University Extension says the level needed varies: sometimes only hardwood or softwood matters, sometimes white oak against red oak, sometimes the individual species, and depending on the level it may take a glance or several hours and a microscope.
The features the sources name
| Feature | What the sources say | Examples they give |
|---|---|---|
| Softwood or hardwood | Michigan State (E-746, 1986) says the names come from needle-bearing and broad-leaved trees and have little to do with hardness; hardwoods have pores and softwoods do not | Pines, spruces and cedars against maples and oaks |
| Diffuse-porous | The Wood Handbook says vessels do not change markedly in size from earlywood to latewood, or change only gradually | Maple, birch, aspen and cottonwood, yellow-poplar |
| Ring-porous | The Wood Handbook says the change is abrupt, with large earlywood vessels and denser latewood | Hackberry, white ash, shagbark hickory, northern red oak; Michigan State adds elm |
| Semi-ring-porous | The Wood Handbook says vessel size and pattern fall between the two | Black walnut, in the temperate zone |
| Softwood ring transition | The Wood Handbook says a few softwoods change gradually from earlywood to latewood and others change abruptly | Gradual: western redcedar, northern white-cedar, spruce, true fir. Abrupt: southern yellow pine, larch, Douglas-fir, baldcypress, redwood |
| Resin ducts | Michigan State says tiny openings along the ring are frequently visible in some softwoods, far fewer than hardwood pores | Pines; large in sugar pine |
| Rays | Michigan State says rays are distinctive in oaks and beech, where they are quite broad, and show on the radial surface in maple | Oak, beech, maple |
Colour, odor and sapwood
Michigan State names three difficulties with colour: it varies considerably within one kind of wood, wood is often stained, and it changes with light. It also says no other American wood has the colour of eastern red cedar. On odor, the bulletin says it helps with some woods, giving Douglas-fir, basswood and the cedars, that an odor can only be learned by comparing with a known sample, and that an old-cut board may lose it. It says only heartwood has characteristic colour and odor, since sapwood has no distinct colour or odor, and that sapwood thickness varies with the species: it gives about 2 inches on ponderosa pine and one-half inch on northern white cedar. The bulletin says softwoods are generally harder to tell apart than hardwoods, and warns that printed grain, overlays and plastic laminates can fool a reader who is not familiar with wood.
About the 1986 key
The Michigan State bulletin was written by Eldon Behr of the Department of Forestry and reprinted in August 1986. The university archive labels the copy as an archive copy not to be used as a source of recommendations, so this page uses it only for the plain wood features above. The bulletin says its key covers only woods hobbyists, builders and furniture makers commonly meet and only three imported woods, and says wood identification takes time and skill to learn. Mississippi State points to a University of Tennessee extension pamphlet on Tennessee woods and to US Forest Service books that describe the wood of each species.
Sources
- USDA Forest Service, Forest Products Laboratory, Wood Handbook (FPL-GTR-282), 2021, chapter 3 (growth rings and wood identification), read October 9, 2026
- Michigan State University Extension, Identifying Wood: a Guide and a Key (E-746, Behr), reprinted August 1986, archive copy, read October 9, 2026
- Mississippi State University Extension, Wood Identification, read October 9, 2026