How to Identify Elm (American) Wood (Ulmus americana)
Elm (American), Ulmus americana: color, grain, end grain, Janka hardness (830 lbf) and weight, and how to tell it from Hackberry, quoted from the USDA Wood Handbook and The Wood Database.
At a glance
- Scientific name: Ulmus americana
- Type: Hardwood
- Origin: Eastern North America
- Color: Heartwood light to medium reddish brown; paler sapwood usually well defined.
- Grain and texture: 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
- Specific gravity (12% MC): 0.5
- Other clue: Strong, unpleasant smell when green, though very little odor once dried; elm (Ulmus) reported as a sensitizer causing eye and skin irritation.
What Elm (American) looks like
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.
Hardness and weight
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.
Elm (American) vs Hackberry
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.
Smell, weight and other clues
Strong, unpleasant smell when green, though very little odor once dried; elm (Ulmus) reported as a sensitizer causing eye and skin irritation.
Where you will meet it
Boxes, baskets, furniture, hockey sticks, veneer, wood pulp, and papermaking.
Working it
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.
How to photograph it for identification
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.
FAQ
How hard is Elm (American)?
Janka hardness 830 lbf. For comparison, Red Oak is about 1,290 lbf and Eastern White Pine about 380 lbf.
How do I tell Elm (American) from Hackberry?
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.
Is Elm (American) a hardwood or a softwood?
Elm (American) is a hardwood: it comes from a broadleaf tree. Hardwood and softwood describe the kind of tree, not how hard the wood is; some hardwoods are softer than some softwoods.
What color is Elm (American)?
Heartwood light to medium reddish brown; paler sapwood usually well defined.
Related
Sources
- https://www.wood-database.com/american-elm/
- https://www.fpl.fs.usda.gov/documnts/fplgtr/fplgtr190/chapter_05.pdf
- https://www.wood-database.com/hackberry/
Updated 2026-09-11.