Search found 386 matches

by Larry Davis
Mon Nov 04, 2019 9:07 pm
Forum: Rose Hybridizers Association Forum
Topic: Odd little seedling
Replies: 12
Views: 408

Re: Odd little seedling

Here's a thought that might pique Karl's interest. Dwarfing of apples, pears and the like depends on rootstock, or interstock grafting. Is there any evidence in he rose literature for such things? I only know the examples of minatures grafted onto standards where you get a small bush on top of a lon...
by Larry Davis
Tue Oct 22, 2019 11:35 pm
Forum: Rose Hybridizers Association Forum
Topic: Question about seed ripening and pollen parent
Replies: 15
Views: 724

Re: Question about seed ripening and pollen parent

I've observed that R pomifera tends to have effect of early ripening in hips for which it is the pollen parent, just as it ripens incredibly fast as a mother, around 2 mo. Probably there is a species effect, but once you mix a few you can really only talk of cultivars. We don't really know the % of ...
by Larry Davis
Tue Oct 22, 2019 9:35 pm
Forum: Rose Hybridizers Association Forum
Topic: Question about seed ripening and pollen parent
Replies: 15
Views: 724

Re: Question about seed ripening and pollen parent

I don't recall ever reading a paper that discusses a pollen effect on seed production/ripening time. But back in the 1950s it was shown by a breeder (in NH?) that the male parent determined time to germination. One mother, several different pollens, average days to germ varied widely. Karl has the p...
by Larry Davis
Fri Oct 11, 2019 11:15 pm
Forum: Rose Hybridizers Association Forum
Topic: Newbie question
Replies: 12
Views: 614

Re: Newbie question

Henry is most certainly correct. So is Don. On the RHA website is a long review I wrote on all the germination papers I could find in about 2014. No big breakthroughs since. Some species have an optimum harvest time. For instance decades ago R canina germinated best at a certain stage of red, fully ...
by Larry Davis
Fri Sep 20, 2019 10:38 pm
Forum: Rose Hybridizers Association Forum
Topic: Newbie question
Replies: 12
Views: 614

Re: Newbie question

About hip picking in autumn. A couple years ago (fall 2017) I had access to a bunch of OP hips on two plants of a yellow HT/grandiflora of uncertain parentage but rather like Julia child. I knew that they had set at midsummer or later but a hard frost was coming. So I cut them off long with leaves s...
by Larry Davis
Sun Aug 25, 2019 3:58 pm
Forum: Rose Hybridizers Association Forum
Topic: Non-fading suggestions
Replies: 11
Views: 530

Re: Non-fading suggestions

First Impression, by Jim Sproul has given me very saturated yellows that last. Not very winter hardy at 0 F or below and will get blackspot if there is any in town. But I've crossed it to get some very good yellows that don't have BS. It resists mildew and can improve it's partner's performance. For...
by Larry Davis
Mon Aug 12, 2019 11:05 pm
Forum: Rose Hybridizers Association Forum
Topic: Lac Majeau x John Cabot
Replies: 2
Views: 173

Re: Lac Majeau x John Cabot

That looks a potentially very interesting rose. Love to see a later bloom which may be even more double and larger.
by Larry Davis
Mon Jul 29, 2019 10:17 pm
Forum: Rose Hybridizers Association Forum
Topic: Why some crosses fail
Replies: 11
Views: 622

Re: Why some crosses fail

I can't say a lot about why crosses fail other than plant incompatibility but about Therese Bugnet there is something odd going on in my experience. AT my house it competes with roots a a neighbor's maple tree and gets enough supplementary water to keep it growing. But it neve gets above 5 ft tall, ...
by Larry Davis
Thu Jun 06, 2019 12:02 am
Forum: Rose Hybridizers Association Forum
Topic: ruby slippers dancing
Replies: 3
Views: 275

ruby slippers dancing

ImageFinally got a decent photo of this one
by Larry Davis
Wed Jun 05, 2019 10:29 pm
Forum: Rose Hybridizers Association Forum
Topic: Seedling
Replies: 33
Views: 2071

Re: Seedling

That Art Nouveau results is great. Shows it is heritable, not just a defect in Art N. itself.
by Larry Davis
Fri May 31, 2019 11:56 pm
Forum: Rose Hybridizers Association Forum
Topic: R. bracteata x Carefree Copper
Replies: 15
Views: 1166

Re: R. bracteata x Carefree Copper

If you want a more direct source of persian yellow, Carefree copper is of course roughly half Austrian Copper. The other half comes out of Griffith Buck's breeding program which sprinkled in R laxa and other less common materials. I assume that the yellow in his was derived from one of the Persian y...
by Larry Davis
Wed May 29, 2019 8:14 pm
Forum: Rose Hybridizers Association Forum
Topic: Seedling
Replies: 33
Views: 2071

Re: Seedling

Really looks good. Winter hardy? BS resistant?
by Larry Davis
Wed May 29, 2019 8:12 pm
Forum: Rose Hybridizers Association Forum
Topic: Seeking R. foetida group pollen
Replies: 1
Views: 151

Re: Seeking R. foetida group pollen

Andre, just sent you a PM.
by Larry Davis
Tue May 28, 2019 8:26 pm
Forum: Rose Hybridizers Association Forum
Topic: Helpful tip plant markers
Replies: 5
Views: 525

Re: Helpful tip plant markers

I found that on ordinary plant labels made of plastic, pencil will erase with mud. Peat moss and artificial potting mixes do not work but a silt clay loam with a little water is really effective. then rinse and write again. Usually brittleness of the plastic is the biggest problem. A little very fin...
by Larry Davis
Fri May 17, 2019 7:21 pm
Forum: Rose Hybridizers Association Forum
Topic: Juvenile bloom in cold Hardy varieties
Replies: 3
Views: 227

Re: Juvenile bloom in cold Hardy varieties

The only rugosa I have ever attempted to cross is Th B. The only pollen donor is R pomifera. But I think that all the offspring are actually ThB only. I feel like the Rp is inducing some kind of apomictic seed production because I never had hips form on ThB before using the R pom. (maybe 1 in 5 yr)....
by Larry Davis
Thu May 16, 2019 10:06 am
Forum: Rose Hybridizers Association Forum
Topic: Stratification period?
Replies: 6
Views: 294

Re: Stratification period?

Philip, I do sort of like you, but with the calcium nitrate added to vermiculite. I check regularly every month for a year while holding the seeds at 4C (40F) in a standard refrigerator from the 1950s. I have also done deliberate cycling like von Abrams and Hand did back in the 1950s. They did 4 cyc...
by Larry Davis
Tue May 14, 2019 6:38 pm
Forum: Rose Hybridizers Association Forum
Topic: Rose Rosette Disease SCRI Review Meeting Slide Presentations
Replies: 3
Views: 265

Re: Rose Rosette Disease SCRI Review Meeting Slide Presentations

The most scary thing to me is that we may get something resistant but a carrier like Typhoid Marigold. I want to see if R woodsii can catch detectable RRD. I have a ton of seedlings. But what if it is a carrier?
by Larry Davis
Sun May 12, 2019 9:35 am
Forum: Rose Hybridizers Association Forum
Topic: Carefree Copper pollen
Replies: 0
Views: 338

Carefree Copper pollen

CC is in full bloom. If you'd like pollen, post a message to ldavis who uses email at ksu which is an edu cational institution. Include your contact information in that message so I can send you some via 1st class mail.
by Larry Davis
Wed Apr 24, 2019 9:56 pm
Forum: Rose Hybridizers Association Forum
Topic: First blooms vs mature blooms on seedlings
Replies: 4
Views: 251

Re: First blooms vs mature blooms on seedlings

That surely deserves a WOW. How is is as a bush? looks like it has avoided the hulthemia spines near the flowers at least. The color shadings are superfine.
by Larry Davis
Fri Apr 19, 2019 9:29 am
Forum: Rose Hybridizers Association Forum
Topic: tissue culture
Replies: 9
Views: 364

Re: tissue culture

So far as I'm aware there has been relatively little interest in propagation by tissue culture, at least acknowledged as such, for several decades. I looked into it with a couple undergraduates when there was someone at U of Wisconsin hort dept doing it. And one of the large companies J & P I think,...