Riparia is shallow-rooted, highly resistant to phylloxera and tolerant of water logged soil. It is most often used in grafting when vigor control is desired in order to produce high quality fruit on vigorous scion variet...
Black Spanish is an older variety that is tolerant to Pierce’s disease (it can carry the disease and thus be a source of infection if insect vectors are present with no reduction in yield, but Black Spanish vines sold ...