Rose breeders familiar with the development of cold hardy (Zone 3) shrub roses know the importance of Frank Skinner’s ‘Suzanne’. It is in the pedigree of some of the Parkland and Buck roses, and nearly all the Explorer Rosa kordesii cultivars.
‘John Davis’ is the staminate parent of the very attractive Explorer ‘Lambert Closse’. Although breeders have been slow to use it, it seems like ‘John Davis’ may be as valuable as ‘Suzanne’ to use in breeding programs to develop cold hardy (Zone 3) roses. It’s likely Henry Kuska was one of the first, if not the first amateur breeder to use it. If I recall correctly, he developed some very good ‘George Vancouver’ x ‘John Davis’ selections. Terry Roszko has developed a very good ‘Morden Sunrise’ x ‘John Davis’ yellow selection. My own work has produced a good but only once blooming ‘Morden Centennial’ x ‘John Davis’ selection, having very double, quartered, peach pink flowers. It is cold hardier than ‘Morden Centennial’. I think there is no doubt that of all the Explorer Rosa kordesii cultivars, to date ‘John Davis’ has been the best staminate parent. I continue to use and will step up my efforts with it. Is anyone else using this cultivar in their breeding programs?
Two years ago I made several similar crosses involving some of my better seed parents in the yellow and red range, using pollen from ‘John Davis’ and L83. I made crosses using “1-72-1” and ‘Golden Angel’ with those two pollen parents and the seedlings are now two years old. Selections from each cross have similar vigor and the best have similar yellow/peach coloring, but there is one glaring difference: foliage health of the L83 seedlings is far superior to the ‘John Davis’ offspring. Most, if not all of the ‘John Davis’ seedlings will be culled this year while several of the L83 seedlings will be used in further breeding. Just FYI.
I like ‘John Davis’ but I’m far less inclined to use it now, having seen these results. YYMV of course. It might depend a lot on what parents you select to mate with it.
‘John Davis’ is triploid and I got both 3x and 4x offspring with it in crosses to 4x female parents. I suspect because of that there can be a lot of variability among its seedlings which is nice too. It definately tends to contribute hardiness. THere is some “op” in its pedigree. I have what I believe to be selfs from it whose seeds were collected from a landscape that was in relative isolation. They have a strong Rosa laxa look to them. I suspect R. laxa of some sort may be in the background of ‘John Davis’. It is a very special rose indeed!!! Super hardy. I wish it was just a bit more disease resistant too, although it is above average for sure. It gets not only some black spot here, but also spot anthracnose and a little mildew, but tends to hold the diseases back relatively well in the right conditions and without a lot of innoculum around.
Sincerely,
David
In 2009 I crossed the following roses with ‘John Davis’ and am now getting germination of the seed.
-
‘Morden Sunrise’. This repeats Terry Roszko’s cross to see how frequently the yellow colour can be in the progeny and perhaps to obtain selections that are more floriferous than his one.
-
‘D’Aguesseau’ - the most sumptuous Gallica I’ve ever seen that I obtained from Palatine Roses a couple years ago. However, the pink colour is lighter than the photos on HMF so the shrub may have been mislabeled. I sent the shrub to the Montreal Botanical Gardens rose garden in an attempt to determine if it truly is this cultivar.
-
‘Suzanne’ - This cross was done for fun and to see how well the seeds of this cultivar germinate. They do so easily. ‘Suzanne’, of course, is in the pedigree of ‘John Davis’.
This year I’m going to concentrate on 'Winnipeg Parks x ‘John Davis’ in an attempt to get a red or at least a deep pink with flowers of very good form. ‘John Davis’ as a staminate parent has the ability to produce this type of flower.
I should mention I also crossed ‘D’Aguesseau’ with Rosa arkansana successfully as part of my project to develop a series of Gallica x Rosa arkansana roses.
Hi Paul,
That’s a great point that ‘Suzanne’ is in the background of ‘John Davis’. So, R. laxa is in the background of ‘John Davis’, although a few generations back on the maternal side. It was amazing to see the very strong R. laxa traits in the op seedlings of ‘John Davis’ that seemed to be selfs (generally isolated landscape). Who knows who the the paternal parent of ‘John Davis’ is. It is interesting it is triploid. It really surprised me at first to count it as having 21 chromosomes. I looked at many root tips and multiple plants because it seemed so suprising and they all were triploid. It is listed as tetraploid in places, but I suspect people just assumed it is. There is no listing of who did a count of it to determine it is tetraploid. Much of what is in the background of what is known on the female side is documented as tetraploid, so one may assume it should be as well.
It sure is a great staple in the landscapes around the Twin Cities and I agree probably has a lot still to offer us as a parent. I should use it more!!! Thank you Paul for the encouragement.
Sincerely,
David
I think I may have this rose, but poorly spoted so it hasn’t gotten very large. I’ll have to ID this particular one, see if I still have it.
Paul your Gallica x Rosa arkansana rose crosses sound fascinating. Nice use of natives. My own gallicas are JUST starting to bloom, and I’ve already had fun just putting pollen on my finger from anything already blooming onto Duchesse de Montebello. It occurred to me today looking at my pomifera that a dark gallica with apple rose’s silver foliage would be rather striking. ‘Tuscany Superb’ luckily has a ton of buds this year- I get to play!
I do hope this small plant I’m thinking of is in fact John Davis, that would be a nice treat.