Search found 372 matches

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: 65

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: 89

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: 129

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: 39

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: 149

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: 7
Views: 165

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,...
by Larry Davis
Fri Apr 12, 2019 10:06 pm
Forum: Rose Hybridizers Association Forum
Topic: first roses of the year
Replies: 19
Views: 391

Re: first roses of the year

I searched as best I could and the closest analogy that might work is photochromism. Some folks have referred to the difference in rose petal color with light intensity (particularly toward the UV end of spectrum) as photoblastic. But that term is reserved for seeds where germination responds direct...
by Larry Davis
Wed Apr 03, 2019 10:02 pm
Forum: Rose Hybridizers Association Forum
Topic: more pics for i.d.
Replies: 5
Views: 158

Re: more pics for i.d.

That lone hip sure looks like a canina after winter. My bushes, seedlings all, vary in thorniness, but generally more than you seem to show. But the reddish stems and buds swelling now is characteristic. Could these have been rootstock? My material came from a huge old bush in PA which was ID'd deca...
by Larry Davis
Sat Mar 30, 2019 10:46 pm
Forum: Rose Hybridizers Association Forum
Topic: Varying Germination with Differing Pollen Parents
Replies: 13
Views: 207

Re: Varying Germination with Differing Pollen Parents

How many seeds did you get per hip? That will tell you something of the compatibility of the two parents. More is better obviously but but the potential # is set by DE. A low # indicates a poor match which might yield a seed that is inviable after partial development. So the hips may contain only em...
by Larry Davis
Mon Mar 11, 2019 11:57 pm
Forum: Rose Hybridizers Association Forum
Topic: Still trying to wrap my head around Canninae meiosis, and how to overcome...
Replies: 12
Views: 251

Re: Still trying to wrap my head around Canninae meiosis, and how to overcome...

About that caninae meiosis as observed with R. pomifera. Some years back I got a seedling for that triploid R pom from David Z. Looks like about 10 yr ago as I had a plant big enough to pollinate in 2010. Crosses have worked apparently both ways but I'm always suspicious of R pom as female parent wh...
by Larry Davis
Wed Mar 06, 2019 9:04 pm
Forum: Rose Hybridizers Association Forum
Topic: First germination of the winter
Replies: 120
Views: 2628

Re: First germination of the winter

Update on my earlier post (pg 2 of this series). Those first germinations have yielded some flowers. One of interest is a yellow, looking very like #1100 in coloring and petalage. The mother is New Dawn x yellow mini which has a different flower shape and a more pink coloration. Another rather doubl...
by Larry Davis
Wed Mar 06, 2019 8:51 pm
Forum: Rose Hybridizers Association Forum
Topic: cherry frost & lemon drift
Replies: 10
Views: 201

cherry frost & lemon drift

On the same page with Pretty Polly series, which look like great roses, there is a bright red by Julie Overom. Has anyone up north (WI, MN etc) seen Cherry Frost in action during its limited distribution last year? Or during earlier testing phase? Seems like it is a much bigger bush than the Polly s...
by Larry Davis
Sun Mar 03, 2019 8:21 pm
Forum: Rose Hybridizers Association Forum
Topic: STUDIES OF THE EFFECT OF SOIL NITROGEN ON THE DEVELOPMENT OF BOTTOM BREAKS AND ON THE NITROGEN FRACTIONS OF THE LEAVES,
Replies: 1
Views: 53

Re: STUDIES OF THE EFFECT OF SOIL NITROGEN ON THE DEVELOPMENT OF BOTTOM BREAKS AND ON THE NITROGEN FRACTIONS OF THE LEAV

Very interesting study, but I think there's a flaw in the recipe for Nessler's reagent. Iodine and KI are not that soluble in water as specified. In addition, it contains so much mercury that on one would dare try to use it today. With modern flow injection analysis there would be no need anyway. Be...
by Larry Davis
Fri Mar 01, 2019 8:01 pm
Forum: Rose Hybridizers Association Forum
Topic: The volume of Acta Horticulturae with rose articles from the meetings in Angers France is out!!
Replies: 3
Views: 131

Re: The volume of Acta Horticulturae with rose articles from the meetings in Angers France is out!!

I regret that since the fire we have had to cancel about $1 million worth of subscriptions, with a freeze on new acquisitions for this year. SO no luck. WE have the other six symposia (maybe) but they are not retrievable until the library reopens next year.
by Larry Davis
Wed Feb 20, 2019 10:55 pm
Forum: Rose Hybridizers Association Forum
Topic: Hardy, Everblooming Climbers
Replies: 55
Views: 1223

Re: Hardy, Everblooming Climbers

I wish I had more than anecdotes on flower timing. But as an example, I have a once-flowering hybrid of something I called Pink Single which was Carefree Beauty x Rise N Shine. Using pollen of an interesting seedling from David Zlesak (nominally triploid R. pomifera) I got a dwarf plant looking for ...
by Larry Davis
Sun Feb 17, 2019 10:23 pm
Forum: Rose Hybridizers Association Forum
Topic: Hardy, Everblooming Climbers
Replies: 55
Views: 1223

Re: Hardy, Everblooming Climbers

I'm sure there is a wide range of hardiness in some species of roses, but I don't know how much in which. It is well known in in the nursery trade that CV of dogwood or redbud that are grown down south and shipped all round the U.S. via bigbox stores often are not hardy. But I sent redbud seedlings ...
by Larry Davis
Sun Feb 17, 2019 7:53 pm
Forum: Rose Hybridizers Association Forum
Topic: Hardy, Everblooming Climbers
Replies: 55
Views: 1223

Re: Hardy, Everblooming Climbers

In the category of sweeping generalizations consider the following. Cold-hardiness is probably for many purposes a quantitative trait. That is, it takes a considerable number of genes. So when you cross two roses of different hardiness categories, you ought to get something about halfway in between,...
by Larry Davis
Sat Feb 16, 2019 7:52 pm
Forum: Rose Hybridizers Association Forum
Topic: Hardy, Everblooming Climbers
Replies: 55
Views: 1223

Re: Hardy, Everblooming Climbers

That article about Risley is very interesting. However, I notice one quirk. American Pillar #84 which I bought many years ago as Golden ARctic (#84) was definitely yellow, not pink. It is parent of my Arctic Sunrise and was quite hardy here to -10 to -20. So i don't know if the naming was changed wh...
by Larry Davis
Tue Feb 05, 2019 10:54 pm
Forum: Rose Hybridizers Association Forum
Topic: 'Chinook Sunrise' parentage
Replies: 22
Views: 586

Re: 'Chinook Sunrise' parentage

I had Sir Thomas L. for years. Beautiful white double flowers on a rugosa-type but glossyish foliage. Sterile as a steer. My recollection was much like what Greenman shows on HMF, no trace of pink color, maybe a little green. No clue on actual winterhardiness up your way. Fine here but we've not had...
by Larry Davis
Wed Jan 30, 2019 10:14 pm
Forum: Rose Hybridizers Association Forum
Topic: Dipping [cut] roses in calcium before shipping
Replies: 4
Views: 76

Re: Dipping [cut] roses in calcium before shipping

Very interesting idea. Any clue what concentration? And would it have to be pure CaCl2 or would a commercial salt replacement (icemelt product) work? Will this work be published perhaps in a hort jnl?