How hard is American Elm and what is it good for?

American Elm has a Janka hardness of 830 lbf (USDA Forest Products Laboratory value at 12% moisture content), making it a moderately soft hardwood. Its split-resistant interlocked grain suits bent furniture parts, hockey sticks, tool handles, baskets, cooperage, veneer, butcher blocks, and turned objects.

Can American Elm be used outdoors or in wet conditions?

It is non-durable in ground contact and insects find it, so it is not suited to exterior or in-ground use, though it takes preservative readily. Notably, it holds up oddly well when fully submerged.

How does American Elm work on the bench?

It saws and machines fine, holds nails and screws, stains and finishes without drama, and steam-bends as well as anything thanks to its interlocked grain. That same interlock tears on quartersawn faces, so keep your irons sharp.

DomesticUlmus americana

American Elm

The wheelwright's wood. The bender's wood. The street tree that left.

American Elm (Ulmus americana) is a domestic hardwood with a Janka hardness of 830 lbf. Its interlocked grain makes it split-resistant and exceptional under steam-bending, with light to medium reddish brown heartwood and strong cathedral figure on flatsawn faces.

Category: Domestic
Janka: 830 lbf
Botanical: Ulmus americana
Shipped at: 6–8% MC

Ulmus americana Eastern North America from Nova Scotia west to Alberta and Montana

Eastern North America from Nova Scotia west to Alberta and Montana.

The interlocked grain is the whole story. Heartwood light to medium reddish brown.

Detail of American Elm grain — figured wood texture, photographed at Raw Heartwood — A close read on the grain. Detail of this specimen

What you see.

Heartwood light to medium reddish brown. Sometimes a green or olive cast. Sapwood pale grayish white, usually well separated. Strong cathedral figure on the flatsawn face — the earlywood ring does the work.

Heartwood color detail of American Elm (Ulmus americana)

Heartwood, this specimen

How the grain runs.

Interlocked grain. That is why it splits hard and bends well. Coarse, uneven texture. Big open pores in a single ring.

Closer detail of American Elm grain figure

Closer in

On the bench.

Non-durable in ground contact. Bugs find it. Holds up oddly well fully submerged. Takes preservative readily. Saws and machines fine. The interlock tears on quartersawn faces — keep the irons sharp. Steam-bends as well as anything in the yard. Holds nails and screws. Stains and finishes without drama. Sour and unpleasant when green. Kiln-dried, it is gone. Reported sensitizer. Dust can irritate skin, eyes, and lungs. Most workers are fine.

The numbers, looked at directly.

Janka Hardness

0lbf

3,690 N. Side-hardness — force to embed a half-inch steel ball halfway into the wood.

Average Dried Weight

0lbs/ft³

560 kg/m³. At 12% MC.

Specific Gravity

0.46/ 0.50 at 12% MC

Basic over green volume; second number at 12% moisture content.

Hardness, in context

A side-hardness measurement. Higher number, harder wood.

Shrinkage — radial / tangential / volumetric

4.2%radial

9.5%tangential

14.6%volumetric

On sourcing

Once the great American street tree. Dutch elm disease rewrote that.

Not on CITES. Not on the IUCN Red List. Dutch elm disease ran through the population starting in the 1930s and still does. Big timber-grade trees are uncommon now. Most of what we get is urban salvage or smaller second-growth — parkway trees, mostly.

What it's for.

Bent furniture parts
Hockey sticks
Tool handles
Baskets
Cooperage
Veneer
Butcher blocks
Turned objects

Worth knowing.

The interlocked grain is the whole story. It is why elm would not split and why it bends like nothing else under steam. Disease-resistant cultivars — Princeton, Valley Forge — are getting planted again. Slow comeback.

Sources & references.

Wood Handbook — Wood as an Engineering Material (FPL-GTR-282) — USDA Forest Service, Forest Products Laboratory (2021)
Silvics of North America: Ulmus americana L. — American Elm — Bey, Calvin F. (USDA Forest Service) (1990)
Ulmus americana — IUCN Red List of Threatened Species — IUCN SSC Global Tree Specialist Group (2018)
Ulmus americana — Wikipedia contributors
American Elm (Ulmus americana) — The Wood Database
How to Identify and Manage Dutch Elm Disease (NA-PR-07-98) — Stack, Roger W.; McBride, Donald L.; Lamey, H. Arthur (USDA Forest Service, Northeastern Area) (1998)
Dutch Elm Disease — Plant Disease Lessons — Stipes, R. Jay; Campana, Richard J. (American Phytopathological Society)

Common questions.

How hard is American Elm and what is it good for?: American Elm has a Janka hardness of 830 lbf (USDA Forest Products Laboratory value at 12% moisture content), making it a moderately soft hardwood. Its split-resistant interlocked grain suits bent furniture parts, hockey sticks, tool handles, baskets, cooperage, veneer, butcher blocks, and turned objects.
Can American Elm be used outdoors or in wet conditions?: It is non-durable in ground contact and insects find it, so it is not suited to exterior or in-ground use, though it takes preservative readily. Notably, it holds up oddly well when fully submerged.
How does American Elm work on the bench?: It saws and machines fine, holds nails and screws, stains and finishes without drama, and steam-bends as well as anything thanks to its interlocked grain. That same interlock tears on quartersawn faces, so keep your irons sharp.

From the library to your bench