Slippery elm

Classification:

Family: Ulmaceae, elm family
Genus, species: Ulmus rubra

Leaves:
Base of leaf is asymmetrical. Edge of leaf is coarsely double-toothed. Leaf texture is usually rough, like sandpaper.

Bark:
Bark is soft, spongy, often colonized by moss.

Flowers:
Flowers are short-stalked, arranged in clusters of 10 to 20, appear before leaves in spring.

Fruit:
Fruit is a thin and smooth papery wing, elliptical, contains one seed in center.

More Information:

Common name, "slippery elm," refers to its slimy inner bark.  The genus name, Ulmus, is from the Latin for "elm."  The species name, rubra, is from the Latin for "red," referring to tree's reddish-brown heartwood.  

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