The image depicts the growing economy of the High Middle Ages in the West and the role of the agricultural revolution in making the 12th- and 13th-century intellectual revolution possible; fewer workers were needed in farming and thus many who heretofore were tied to the land were free to move to the growing towns.
The image was taken from John P. McKay, B. D. Hill, and J. Buckler, A History of Western Society, Volume A: From Antiquity to 1500, 7th ed. (Boston: Houghton-Mifflin, 2003), p. 294. The caption states "Allegorical harvesting scenes from a German manuscript, Speculum Virginum, ca 1190." The original painting can be found in the Rheinisches Landesmuseum, Bonn, Germany.