After an early career as an artist specializing in illustration and then industrial design, where he trained under Raymond Loewy, Stoltenberg in 1960 set up a studio in Boston and worked primarily as a marine painter. His paintings stylistically have abstract expressionistic leanings.
The artist also worked in and taught graphic design and methods, authoring multiple books on the technical aspects of printmaking.
He won numerous awards for his work, which has been included in major exhibitions of contemporary art throughout the country, most noteably at the Metropolitan Museum of Art, New York City, the Art Institute of Chicago, the Boston Museum of Fine Art, the Corcoran Gallery of Art and many others.
His works are in the permanent collections of the MFA, Boston, The Boston Public Library, the Worcester Museum of Art, The Decordova Museum, the Addison Gallery and many others.
"Tree Trunk", titled, and dated on an exhibition label from the Kanegis Gallery in Boston and signed lower right front by the artist is 36 x 50 inches. Its style mirrors the heavy paint application and broadly sweeping brushwork of artists like Motherwell, Kline and DeKooning. He works in this decade in a reduced palette of blacks and white with color mixed into heavilly textured paint.