Amount of pollen produced by species and their hybrids

In the Wageningen Botanical Garden there are several plants of R. virginiana and the clone Harvest Song. I took anthers and blooms from those plants, but when dried the anthers did not release a lot of pollen.

There is also a plant labeled R. virginiana x R. macrophylla. Maybe the label is not correct, but at least it looks different from R. virginiana, but not very different. (I haven’t found R. macrophylla yet, so can’t compare). Anyway, the flowers look like r. virginiana, but they have more anthers and lots of pollen. Since the hybrid should be triploid I expect lower fertility. However, with the amount of healthy looking pollen, it seems a better pollen parent than R. virginiana itself.

What is your experience with the amount of pollen R. virginiana blooms give you?

Does anyone have R. virginiana x species that produce a lot more pollen than R. virginiana itself?

Rob

All of the R. virginiana clones I have worked with, including ‘Harvest Song,’ make tons of pollen. The compatibility of that pollen with other roses varies, but some, also including ‘Harvest Song,’ have very good compatibility with modern roses.

I just finished spending more than an hour emasculating flowers on a ‘Yellow Jewel’ x R. virginiana ‘Harvest Song’ hybrid. I am not sure about its female fertility yet, although such hybrids are usually fair to good females. R. virginiana itself seems to be a poor female parent with modern rose pollen. This hybrid plant worked well as a pollen parent last year. I have about a dozen R. virginiana ‘Harvest Song’ hybrids in bloom now, and somewhat less using other virginiana and R. carolina clones.

Poor pollen shed from species might be because the bees already got the pollen. I found that I had to literally get up early in the morning to get pollen just as the flowers opened. Buds just short of opening are also good sources, but smaller buds may appear more mature than they are, and they will fail to produce pollen if they are very young. Such an early bud on a modern rose would be early impossible to emasculate, but single species are easier.

Roger, thanks for your reply. I remember my R. virginiana flower to be already almost open when I harvested it. During my later visits I took scrolled buds of other species roses (didn’t try R. virginiana anymore) and those flowers gave me a lot of pollen. I will try Harvest Song again.

Do you know anything more about Harvest Song than what is mentioned on HMF?

Rob

Have you tried using a morter and pestle to grind the dried anthers? Ralph Moore put me on this tip years ago. He said many roses don’t release much pollen, though the anthers contain it. He’s been grinding them for years with apparent success. Kim

I do that, Kim. I use the ends of my paint brushes I use to spread pollen with.

I usually “squeeze” the pollen against the nail of my index finger against the inner container’s wall.

I got several pollinations from a single bloom of Ralph Moore’s recent introduction “Persian Sunset.” I doubt my tiny little plant from uncommonrose will bloom again until its established.

I got SEVERAL pollinations done with one single plant… 2 hips on Queen Elizabeth, 2 hips on my Abraham Bayse seedling, 2 hips on Heidi mini moss, and 1 hip on Pacific Serenade (which is becoming my famous hip parent.)

Anyways–

Yes, I noticed Pacific Serenade is very fertile and its seedlings passes on very nice dark green miniature foilage. I have a very deep yellow seedling that has Rugelda as a pollen parent. This one may be a micro-miniature by the size of the foilage.

I actually know very little about R. virginiana ‘Harvest Song.’ Past contributors to this forum have mentioned it as one of two clones circulating in Europe. I purchased mine from Heirloom roses, and they may have imported it. Many North American nurseries seem to sell a different clone that has no name, or at least they are selling very similar forms. I had previously purchased an unnamed clone of R. virginiana from Heirloom, and it was the more common form. ‘Harvest Song’ is slightly shorter, and has more glandular hairs (trichomes) on the flower buds. Both this and the commonly available form seem to be quite fertile.