Plant Spine - Gardening Place

Spinescence (a general term for the phenomena of spines, prickles, and thorns on plants) is an important functional trait shared by numerous plant families worldwide and mainly provides physical ... Does anyone know of a eastern tree, suitable for zone 6, that has an interesting winter silhouette? I like the look of a black gum a few streets over, but I want to make sure that I do't over-look any other, possibly nicer ones, as this will probably be the last tree I ever plant.

Thanks.