I have used the bush enough in my breeding work to know that it is quite compatible with garden roses generally, both as male and female parent. The same is true of Commander Gillete, a thornless descendant of R. carolina which I described in the 1985 American Rose Annual. These two roses are tetraploids and together involve the three species, rugosa, abyssinica and carolina, all of which have high resistance to blackspot. Might these two roses be useful in the problem of ridding our garden roses both thorns and blackspot?
I believe that the governing genes for thorns are quite few in number and that thornless roses should soon begin to appear in our gardens.
For blackspot I hold a different view. For 30 years I have shattered many a lance on this worst enemy of the rose, with very little to show for it except hard experience. I believe the problem is difficult because the governing genes are probably many and give no visible of their individual contributions, thus preventing us from dealing with them one by one. Then there is the powerful temptation by the breeders to pursue the lovely blooms, neglecting all else. These are the two main reasons why we continue to bear the burden of cruel thorns and debilitating blackspot. There is a clear need for some dedicated young rose breeder out there to take on the problem, someone who believes that the glory lies as much in the bush as in the flowers.