Andrea Palladio emphasises the usefulness of the lay-out in his treatise. He points out that the grain stores and work areas could be reached under cover, which was particularly important. Also, it was necessary for the Villa Emo's size to correspond to the returns obtained by good management. These returns must in fact have been considerable, for the side-wings of the building are unusually long, a visible symbol of prosperity. The Emo family introduced the cultivation of maize on their estate (and the plant, still new in Europe, is depicted in one of Zelotti's frescoes). In contrast to the traditional cultivation of millet, considerably higher returns could be obtained from the maize. It is not clear if the long walk, made of large square paving-stones, which leads to the front of the house, served a practical purpose. It seems to be a fifteenth-century threshing floor. However, Palladio advised that threshing should not be carried out near a house.