Grapevines are propagated primarily by cuttings just as they have been for years. The use of seeds for propagation is not satisfactory, because the seedling does not resemble the parent vine. Work by F. T. Bioletti in the 1920s indicated that production of new vineyards was the same whether or not the original cuttings arose from vines that bore heavy crops or light crops. The difference was caused by the environment and was not inherited.