How to Identify Elm (American) Wood (Ulmus americana)

Heartwood light to medium reddish brown; paler sapwood usually well defined. Grain is interlocked (making it very resistant to splitting), with a somewhat coarse, uneven texture. End grain: Ring porous; large to very large earlywood pores in a continuous row one or two pores wide, small latewood pores in wavy bands; tyloses occasionally present in earlywood; growth rings distinct; parenchyma vasicentric and confluent; medium rays, normal spacing.

Janka hardness 830 lbf (side hardness: the force needed to embed a 0.444-inch steel ball to half its diameter). Specific gravity 0.5 at 12% moisture content, so a cubic foot weighs roughly 31 lb. Weight in the hand is one of the quickest checks: compare a piece of known size against a board you already know.

American elm's wavy latewood pore bands and interlocked grain are shared across the elm-hackberry family; rock elm is notably denser/harder than American elm, while hackberry closely resembles ash in surface color but shares elm's characteristic wavy-band pore pattern on the endgrain. The Hackberry page has its own details.

Strong, unpleasant smell when green, though very little odor once dried; elm (Ulmus) reported as a sensitizer causing eye and skin irritation.

Boxes, baskets, furniture, hockey sticks, veneer, wood pulp, and papermaking.

Can be a challenge to work because of interlocked grain, especially on quartersawn surfaces, with possible tearout/fuzzy surfaces when planing; glues, stains, and finishes well, steam-bends well, and holds nails/screws well.

Photograph a freshly cut or sanded face in daylight, not a finished or stained surface, since stain hides color and finish flattens grain. Add a close-up of the end grain: cut a clean end, wet it or sand it to 220, and shoot from straight on; pore pattern and rays are the most reliable marks. Put a ruler in frame. The app suggests the likely species; confirm with the end grain and weight.

If the elm is still standing, the leaf is the fastest check: alternate, 3 to 8 in. long, with double teeth and a lopsided base (Morton Arboretum; Wikipedia). Siberian elm, a widespread invasive look-alike, has smaller, single-toothed leaves with a nearly even base, and slippery elm has leaves rough above and velvety below with rusty, hairy buds (Wikipedia). Without leaves, look for the vase shape. See American elm leaf identification.