 Despite this impressive impact, Rogers' hybrids are the product of only two crosses.Rogers pollinated a vine of "Vitis labrusca", known locally as Carter or Mammoth Globe, with pollen from two European "Vitis vinifera" grapes, Black Hamburg and White Chasselas, being cultivated under glass nearby.He planted the resulting seeds in his garden, and the next spring approximately 150 germinated, but cutworms and other pests and accidents reduced their number to forty-five.