An older friend who does not use email/internet called me today to ask if platanoides can be grafted on pseudoplatanus rootstock? I told him I do not graft but would put the question to a forum of maple experts to which I belong so... I told my friend that on page 301 of Le Hardy de Beaulieu's An Illustrated Guide to Maples, the author says, "One advantage of the sycamore maple is that it can be used as rootstock for propagating most maples, even those belonging to a different section." Any experiences and advice I can pass on? Thank you.
Although I don't have personal experience with this, the conventional wisdom is that grafting on the same species is more likely to produce good long-term results, or at least within the same section. Here he would be grafting across sections--section Platanoidea (platanoides) onto section Acer (pseudoplatanus). I recall reading somewhere--I don't recall where, I'm afraid--that although grafts of many species on pseudoplatanus do take initially, there are concerns about delayed graft failure. All seems to go well for a few years or a decade, but the graft union doesn't knit fully, and the trees are more susceptible to damage at the graft later in life. But this isn't authoritative--just a remembered impression. I bet the van Gelderen's would know for sure. I would think that truncatum or campestre might be better, because they are in the same section as platanoides, although I wonder what happens when you graft a big tree such as platanoides onto the understock of a species that is naturally smaller, such as truncatum or campestre. If the graft takes, do you end up with a wider trunk perched on a narrower one? I've seen photos of such things. If he has the option, I'd suggest that your friend order some understock from a place such as ForestFarm to give himself the best chance of success. Dan
Dan, thanks so much for your informative reply which I will pass on to my older friend. The "remembered impression" is priceless and perhaps I will send an email to Cor van Gelderen as you suggest. Many thanks. Mike
Must admit I'm baffled why one would want to graft Acer platanoides onto anything different in the first place - Acer platanoides is one of the easiest maples to get hold of seedlings for rootstocks. Usually its seedlings are so abundant as to be considered an invasive nuisance.
Mike, I thought the line at inter-section grafting was that maples with latex could not be grafted to those without. IIRC platanoides has latex, (not sure didn't look it up). Last year I received a young graft of section macrantha that did not survive. As is often the case the understock started to grow after the rejection, I was surprised to find it a sycamore.... I queried the grower and was told they use sycamore "when nothing else is available." Needless to say this didn't give me a great feeling. -E
Hi Katsura, I visited today with the very person you spoke with. He's a good man and he found a very interesting Norway broom. I don't mess around with A. platanoides, although I have paid a saw/bucket man to kill and grind a couple on my property. I laughed reading Michael F's comment... good point. Brian
If the broom is a non-flowering form it would never contribute to the severe weediness of Norway Maple in North America - I have seen an unbelievable infestation even in dry-summer Seattle, where these are (so far) seen going wild only sporadically - unless there was a tendency for unattended specimens to be overtaken and replaced by the seed-producing (Norway Maple) rootstock. Delayed incompatibility is probably more prevalent among shade, flowering and nut trees than is generally apparent. In one instance English walnut orchards were planted on black walnut rootstocks only to fail just as the trees came into full productivity, resulting in disaster from a business standpoint. Years of investment without a return. More vigorous trees grafted onto smaller- or slower-growing rootstocks can and do result in a thick trunk bulging out from above a markedly narrower pedestal. An example I've seen is larger growing Yulania magnolias grafted onto Kobus magnolia stocks. One such tree at the Seattle arboretum may have been declining for years because of delayed incompatibility. A very common example of the reverse balance in size and vigor is Higan and other more delicate or dwarfish Japanese cherry cultivars grafted onto Mazzard cherry rootstocks. A rather small tree may end up perched atop a massive stem.
Thanks to all my forum colleagues for your great input on this thread all of which I just read over the telephone to my friend who does not use computers. Scion swapper, he confirmed he saw you Monday and had kind things to say about you as well. Best regards, Mike aka 'katsura'
I also am not wanting to graft a Norway Maple onto a Sycamore Maple seedling rootstock either. People forget that the main reason for interspecies Fall, Winter and Spring grafting as well as Summer budding in some cases is not done out of convenience but to add in vigor into the host plant. We more likely will not see vigorous offspring as a result from an Acer platanoides x Acer pseudoplatanus scion to rootstock marriage. I agree that Norway Maple is best grafted on locally grown, not imported or transported in, seedling rootstock instead. The main issue with broom growth finds is that we want to have a neutral rootstock. One that will on one hand provide some vigor in the finished product tree but also will not force or later enact a change in the broom. This area of concern is the problem area in how the palmatum 'Aratama' changed on us in that at first we had a stubbed middle lobed broom that when grafted onto a green seedling rootstock over time yielded a loss in the stubbed middle lobe as seen on a number of current day plants. The purists kept the Aratama on its own roots so that it was less likely to change back to the normal leafed plant, albeit still a dwarf Maple until it had been propagated solely by grafting for a number of years and then became a semi-dwarf plant for some people. We also are not well informed about how Acer pentaphyllum was sustained either in that the original grafts from the Rock plants were grafted onto Sugar Maple (Acer saccharum) to help save the Yulan plants but to sustain this Maple over time, seedlings grown from the grafted plants were used as the primary rootstock from then on until through the efforts of two nurserymen and the Occidental plant that others had access to seed from the second generation grafted plants that would yield pentaphyllum leaves. So, in effect a broom from a Norway Maple can be saved grafting scions onto a Sycamore Maple to hold it for the short term but for the long term this broom is better served to be perpetuated back onto a Norway Maple rootstock. Ron, Kobus as a rootstock was never meant to be a long term panacea for the Yulan Magnolias, neither was Grandiflora either. They were meant to be short term parent rootstock plants to hold or keep the scion plant viable until a better or a more widely available Yulan rootstock could be used as the long term rootstock of choice for the selected Yulans. The dilemma was that only a few people were growing seedling Yulans after the long wait to see their trees flower and set seed. Once the 15-20 year wait was over and seed was available then it was learned in some select circles that seedling Sprengeri and better yet seedling sprengeri ‘Diva’ were more compatible for a host of Yulan types. Kobus did fine for the short term to hold the plants over until a better rootstock could be found. Also, this was at a time when only a couple of people really would even think of devoting any Diva plant to be a seed source parent for grafting. Everyone else wanted to have the Sprengeri seedlings to monitor for other colors or to sell the seedlings as Sprengeri. There was not a market for Diva seedlings 30 years ago and you already know why this was, as too many of the seedlings were not as colorful, not as pronounced or "as rich a pink" (was the rationale told to me and seen firsthand as well) in many cases as the Diva plants were that had been perpetually propagated by rooted cuttings and later on in the late 70's, early 80's by way of grafting (to speed up the time it took for these plants to set flower buds). Jim
great post, Jim, as usual. I never knew that about 'Aratama' which is one of my very favorites. Both mine are ablaze right now in new Spring red leaf - both have the foreshortened spatulate center lobe. Because I do not graft I never thought of the effect the rootstock had on the scion until you kept posting about this very point about which u seem very right. Thanks again.
Seedlings of the 'Diva' at Caerhays and also at the USNA have had a problem with turning out to be crosses with white saucer magnolias planted nearby. Otherwise the pink Sprenger magnolia reproduces true in the wild and in cultivation, when not contaminated by pollen of other kinds of magnolias in collections. Several other cultivars have arisen from cultivated stock since the pink 'Diva' at Caerhays first flowered. These include 'Claret Cup', 'Copeland Court' and 'Eric Savill'. The latter is known for producing stunningly colored reddish flowers which also unfortunately tend to feature ugly wrinkling of the tepals. Sprenger magnolia also occurs with white flowers in nature, and perhaps plants with white flowers (other than var. elongata) are in cultivation as well. A private garden in Seattle has what appears to be one such. However, without genetic testing or some other certifying means it cannot be certain that it is not a hybrid with mostly Sprenger magnolia characteristics. There is also a white (or extremely pale pink) flowered seedling in the Seattle arboretum that is recorded as having been collected in the wild. It produces erect flowers superficially resembling those of M. x veitchii but the foliage is like that of Sprenger magnolia - if I have compared the flowers of these two to one another up close I don't remember the outcome. A recent article in The Plantsman shows and describes Sprenger magnolias found in the wild in China and addresses a few of the questions about it based on experience in western cultivation that have lingered for many years. The article mentions white flowered plants being known there but does not mention var. elongata (at least by name) at all, making it unclear if they are talking about a second white-flowered type or this. Further investigations are said to be planned so more information about the white forms in the wild may appear. http://www.rhs.org.uk/Learning/Publications/plantsman/1208/plantsmandec08.htm
I agree with Jim, use any understock you can get your hands on to "save" the broom, but look long-term toward finding A. platanoides understocks. Brian