Does any information on the following roses w.r.t. fertility? Not widely grown roses as far as I can tell so there seems to be little information about them. I may try to get either some or all of them.
Mrs. John McNab
Each year (including this past year) I collect some open pollinated seeds from both my Wasagaming and the one in a public garden.
I do not remember ever getting a seed to germinate. I should try the pollen.
Will Alderman (apparently a “sister” of Wasagaming) works both ways.
I have some (Rugelda X OP) X Agnes seedlings growing now that have Agnes as the pollen parent. I am not sure if they are from diploid pollen or from flowers from branches that have had their chromosomes doubled by my use of Preem.
‘Postjarnen’ - likely fertile both ways (definitely as a pistillate parent). Since it is an extremely hardy (Zone 2) Climber, it has great potential to increase hardiness of this type of rose.
‘Mrs. John McNabb’ - I don’t recall it ever setting op hips. Staminate fertility unknown. I never think of this cultivar as having potential in a breeding program.
‘Dr. Merkeley’ - infertile both ways (petals are too double). Pickering’s description of it as a Rosa spinosissima cultivar is incorrect. It is likely Rosa majalis.