Wood Species Guide
Rock Elm
Ulmus thomasii
Also called: Cork Elm, Hickory Elm, Northern Elm, Cliff Elm
What Rock Elm looks like
Heartwood is light to medium reddish brown, and the sapwood is a lighter cream to tan. Color is more even than American elm.
Grain and texture
Interlocked grain with a fine to medium texture and much tighter growth rings than other elms. It is far denser and more uniform than soft elms.
Working Rock Elm: planing, cutting and gluing
Hard, heavy and very tough, with interlocked grain that resists splitting. It can tear out on the planer, so use sharp knives and light passes. It steam-bends extremely well and glues fine.
Finishing Rock Elm: oil, film finishes and epoxy
Takes oil and film finishes well. The grain is tighter than other elms, but a seal coat before an epoxy pour is still a good idea. Color warms slightly with age.
Durability, stability and Florida humidity
Not rot resistant and open to insect attack. Like all elms it can warp while drying, so buy well-dried stock. In Florida, acclimate the boards indoors and finish both faces.
Shop notes from our Fort Myers shop
Rock elm is the toughest of the American elms, the old choice for hockey sticks, boat ribs and wagon hubs. It is scarce now, so most of it goes to bent parts and specialty work. If you need a strong, bendable hardwood for a chair or boat project, it's worth hunting down. We don't stock it, but ask us and we can often source it.
Common uses for Rock Elm
Bent parts, boat ribs, hockey sticks, chair parts, tool handles, furniture and veneer.
Sustainability and CITES status
Not listed in the CITES Appendices or on the IUCN Red List. Mature trees are less common since Dutch elm disease spread across its range.
Safety and toxicity
- Skin irritation
- Eye irritation
Elm dust occasionally irritates eyes and skin, and a few allergy reports exist. Serious reactions are rare.
- In the shop
- Dust collection + mask when sanding
- Food contact
- Use with care for cutting boards, bowls and utensils
General information, not medical advice. See a doctor if you have a reaction.
Elm dust can act as a sensitizer, usually as eye and skin irritation. Use dust collection and a mask.
Rock Elm in stock now
Ask us. We can often source it.
We don't have Rock Elm listed online right now, but new slabs and lumber come in all the time and not everything makes it to the website. Tell us what you're building and we'll check our racks and suppliers.
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