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wHAT'S up with elm are three kinds of species: white, red and

Some of its major uses are decorative veneers in boxes, baskets, crates, and slack barrels; furniture; wall paneling; novelties, and specialties.

Two species can be found in the Southern, Central and Lake states of the United States: white elm (Ulmus

Story at a Glance

Elm is prized for beauty and water resistance... stains and polishes well ... is nondurable.

americane, also known as "Southern soft elm," American elm, gray elm, soft elm, water elm, and swamp elm) and rock elm (Ulmus thomasi, also known as Canadian rock elm, cork bark elm, and hickory elm). Other important species are the European English, Dutch and wych elm and the

Japanese nire.

In general, elm has an interlocking grain pattern and a strong, swirling figure when polished. The heartwood is light brown, often with a red tinge. The wide sapwood is nearly white. The growth ring figure is prominent with coarse texture and an often irregular grain.

Specifically, rock elm has a light brown heartwood, with no distinction between sapwood and heartwood.

White elm has a light grayishbrown to occasionally pinkish-tobrown heartwood, with grayishwhite to light-brown, wide sapwood. Similar to ash. the wood found in old-growth stands in the Great Lakes region tends to be a uniform gray.

Found in Canada down through the Midwest of the United States to the Gulf of Mexico, brown elm has a dark brown to reddish-brown heartwood with a thin lighter-colored sapwood.

Red elm has a reddish-brown to dark brown heartwood with grayish- white to light brown, narrow sapwood.

The trees are classified as hard elms and soft elms, based on the wood's strength and weight. Rock elm, winged elm, cedar elm and September elm are classed as hard elms, while slippery elm and American elm are the soft elms. Hard elm species are somewhat heavier than soft elm, while soft elms are highly shock resistant, hard and stiff, and moderately heavv.

White elm has a specific gravity of .50, identical to rhat of tupelo, sweet gum and magnolia, and a weight of 35 lb./ft3. The wood has medium bending and crushing sfrengths, medium density, very good steam bending classification, low stiffness and very high shock resistance.

Rock elm is denser (about 49 lbs. per ft. in the seasoned condition) and more difficult to machine than other elms. It tends to burn with all saws, and char in mortising, boring, and cross cutting.

The wood can be nailed. screwed or glued satisfactorily, and stained and polished nicely. Its toughness and resistance to shock is superior to ash and nearly as good as hickory.

All elm is non-durable, does not take preservatives readily, and tends to distort if irregular grain is present.

It is not particularly strong or stable, with a tendency to warp and crack, making it difficult to machine or work with hand tools.

However, elm fares well in waterlogged conditions, making it useful for underwater parts in dock and wharf construction.