I've spotted a 'ton' of blooms forming. Hybrid potential is tremendous.
Yucca fila/flaccida x rostata (Thomas B seed)
Yucca flaccida 'Tenn big bloom form'
Yucca arkansana 'Moud City, MO'
Yucca glauca ssp. stricta 'Maxwell, NE'
Yucca flaccida x gloriosa 'Benny hybrid'
Yucca 'constricta x filamentosa' X 'filamentosa x elata'
Yucca constricta x filamentosa
Lots more too!