Niels Ebbesen Hansen (January 4, 1866 – October 5, 1950) was a Danish-American horticulturist and botanist who was a pioneer in plant breeding. Hansen searched for new grasses, fruits and other plants throughout Europe and Asia. He brought these plants back to America to raise or crossbreed with American varieties to produce a stronger plant. He was the originator of many new fruits, among them the Hansen hybrid plums. He is credited with the discovery and introduction of hardy Cossack alfalfa, crested wheat grass and brome grass. He developed larger apricots and plums by crossing native varieties with those he brought from Asia. This collection consists of photographs, articles, and other materials written by Niels Hansen, during his time at South Dakota State College.