Hi Dianne, very often, you can't tell the difference between Aunt Gerry and Lanvin. I've had both. Aunt Jerry still grows at my sister's house. Personally, if you have one, you have the other. Just not THAT different, at least around Los Angeles.
Ive never seen either in person before. Likely because Oregon is not suitable. What I notice in the photos is that Aunt Gerry has more narrow petals (reminding me of the King's Ransom types), but this could also be environmental.
A small part of me wonders if the unknown portion descended from 'Ivory Tower', but that doesn't seem quite right. It wouldn't explain the mildew resistance some are claiming, although it would explain some traits. The breeder also used (Bewitched x King's Ransom), which could explain some things. Both ideas fit the appropriate timeline. But it doesn't seem quite right.
It is too bad some things aren't known. Oh well :]
Outstanding yellow HT for our climate (Zone 9B). Capable of prodigious bloom production when well grown. Blooms borne singly and in giant clusters. The spring bloom in April tends to be light yellow with a bit of green, not very attractive in my way of thinking. In the summer and fall the blooms are a pure rich medium yellow. Form is generally good but the rose has a hard time competing with the modern exhibition lions. Outstanding plant with very good mildew resistance. Hard to find, my bush was propagated from a bloom obtained at the end of a local rose show.