Hello, First post to this forum. Does A. shirasawanum make emergency buds if the buds set in fall have dried out? I have a very sad 'Aureum' that suffered through a tough winter. It was planted last spring, about 1 m high. Grew well, set buds etc, but all are dead and dry except on one small branch near the base, which is now leafing out normally. The main stems are green when scratched, but no signs of anything else happening. Should I cut back, or wait? Some of the smaller shoots are of course very obviously dead. Interestingly a small 'Autumn Moon' planted at nearly the same time did fine, and has no die-back at all, even though it is in a much more exposed situation, both wind and sun. Thanks for any advice. -E
Following up. I just spoke to the nurseryman about the tree. He says it has phytophtora from the description. His treatment is to water 1.5 g/l of Aliette. This is a systemic fungicide available in France, it may be available elsewhere or there may be an equivalent (benomyl?). He also recommends feeding with 12/12/18 granules, then repeating the Aliette on 15 june. I'm dubious about the feeding, but might give it a try anyway. I guess the idea is to promote some leaf growth. I don't find any reference to phytophtora in my maple books -- the usual suspects -- does this ring a bell with anyone? Any advice? -E
At the 2005 International Maple Symposium we did learn that Acer are susceptible to Phytophthora ramorum, but this is in its infancy. I am highly suspicious, however, of this nurseryman's capabilities of diagnosing the problem as such, wonder at him mentioning Phytophthora at all, and even more at his unique treatment of the problem. A brief search on google regarding diagnosing P. ramorum leads to symptoms other than what you describe, which we actually often see in maples. I hope that this nursery offers a year guarantee and that you can return your tree, but personally I would not deal with this nursery again after that. I would not subscribe to that treatment plan, but rather would fertilize both specimens rather lightly, as we typically do maples. If you keep the tree, I would await further response on how some of our members deal with this problem of branches of nonproductive buds, given that you have one branch which has leafed out. Personally I prune the dead twigs, but I have not experienced the majority of a tree not leafing out. Were the soil conditions the same for both specimens, e.g. a sandy loam with good drainage?
Does yours look like mine. http://www.daj.fseltd.btinternet.co.uk/Shirasa.htm as you can see mine is very poor this year There is nothing visible on the trunk or branches to infer disease. thanks Don
My experience is that, even without being 100% sure about the causes, if in a branch the buds dry out without producing any leaves, that branch is lost: no new leaves will sprout. Cordially Gomero
Thanks for the responses -- replying multiply. First, apologies for a lack of precision. The fungus cited by the nursery was Phytophthora cinnamomi, not P. ramorum. I wasn't sure before as my French didn't quite keep up with him as he was spelling it, so I lost an 'h' and couldn't find it in google. Don, as I said on the usenet forum mine is very similar, only the branch with leaves is lower down. Thanks, now I don't have to post a pic! Laurie, thanks very much for your considered reply. I am also very suspicious of his claim, but I must say he is a nurseryman of considerable reputation -- not all good! -- and holder of several national collections. I have had mixed results with his plants -- unlike Esveld where the quality is always in my experience irreproachable -- but some are very good indeed. I got a very good Kalopanax septemlobus var. maximowiczii this spring from him, don't know where else I could have found it! He had a very large maple collection including some rarities like diabolicum but following family illness most of these trees seem to have been sold and not renewed. This said I have considered stopping using him as a source. His advantage is that as he is domestic any shipping charges are lower. I haven't found many good maple sources here in France, sadly, I hope some members will enlighten me! Sadly the guarantee is only good for the first growing season, not this year. Is it your opinion that the Aliette would adversly effect the soil chemistry? In regards to soil, the differences between 'Autumn Moon' and 'Aureum' are minor. The latter is in an "easier" location, getting only morning light, and good wind protection from prevailing winds. Both have my usual soil prep, local heavy acid soil mixed with some peat and some ericious soil, along with rotted seaweed compost (or brun). I've been reasonably succesful with this mix. The main difference is provenance and size: 'Autumn Moon' is a young plant from Esveld. Thanks Gomero. Certainly the branchlets are lost. My question was whether there is hope that the main trunk may set emergency buds. There may of course be no certain answer to this, just wondering if anyone has observed this on A. shirasawanum. I have seen this behavior on japonicum, for example. regards to all, -E
E The trunk on my tree has started emergency buds but remain at the very bottom. I will take a few more pics of this area and put them on my original page. Don
there we go.... http://www.daj.fseltd.btinternet.co.uk/Shirasa.htm E what part of the UK are you. I am Winchester, Hampshire. Don
ooooops sorry you're in France.......I was confused as you had originally posted on the UK gardening NG. Don
Don, actually I'm in Basse Normandie, south of Caen. As the climate is very similar I sometimes participate in urg. Looks like your maple is anxious to get on with things! -E
emery- i was wondering about your soil preparation, just to consider other reasons for the tree's condition. You write this that you work in local heavy acid soil mixed with some peat and some ericious soil, along with rotted seaweed compost (or brun)'. Do you add all 3 to your existing soil, or is the soil on the site heavy and acidic to which you add peat and 'terre de bruyère', for ericacious plants, plus fertilizer? In any case it could be problematic to add peat and 'terre de bruyère' (if that is what you are adding), because it could easily produce an overly wet situation round the rootball, and lead to rot (or it could dry out in the summer, even if you water). This because amending the hole - creating an area different from the surrounding soil - can lead to adverse water movements. Look for discussions of peat in this forum for more info. I live in Luxembourg, but also work in France - I have noticed that japanese maples in France are defined as 'acidophilic', meaning that they would need a very acidic soil, like rhododendrons, so people are encouraged to use the same soil for ***. maples, as for rhododendrons and azaleas, meaning peat and 'terre de bruyère', soil for ericacious plants. In my experience, and I have also discussed this with three growers, in France, Belgium as well as one of the van Gelderen (Esveld), maples need slightly (PH around 6) acidic soil, but - as you will see, if you investigate some of the threads in this forum - no peat (not in pots, or in situ.) The tree might also not need the initial fertilization, if you plant in situ. Of course, I am only speculating - just to widen the scope of your investigation, but may be you thought about all this. I had a shirasawanum aureum die on me pretty fast due to scales. It was also in a container with a mix that didn't drain well. I suspect it could be a more fragile tree, but others might know more. Hope the tree pulls through. all best, schusch
Hello Schusch, I look forward to searching the forum to see if there is a consensus on peat. I have heard different sides of this story. Certainly your point about water movement is important and well taken. My problem is that if I do not amend the soil considerably, I have a very low success rate on planting. That is because the soil is really very heavy, and plants coming from better draining media have a difficult time of it at first. So -- and indeed depending on where in the garden I am digging -- I try to add as little as possible of peat and terre de bruyere to get the consistancy better. I don't think there is usually enough of the latter to do all that much. I also put down agri-fleece and mulch heavily with flax (paillette de lin). As for watering, I do so for the first summer for plants that are planted in spring, or not at all for fall planted, unless there is severe heat or drought. (as in the last couple of years, as it happens.) Shirasawanum 'Aureum' was watered last year. I don't think the soil is the problem with this maple, unless whatever I'm doing wrong is multiplied because of its delicacy. Certainly could be, I suppose. If it's not indiscreet, may I ask what other sources you are using in France and Belgium, besides the van Gelderens? best regards, -E
Emery, A few thoughts for you. Phytophthora can affect maples, but it is not terribly common and it has been mentioned, there are a number of forms and means by which it acts. You mention that the branches or twigs seem okay other than the buds seems dry. I believe it is common that the buds will show some blackening with Phytophthora and just to have them dry may not be enough to diagnose the condition correctly. It has been my experience with shirasawanum Aureum, or what is actually japonicum Ogon itaya (as many are, and also sold as japonicum Kinkakure) that verticillium is the pathogen that prevents our branches from leafing out, but we do not see the early signs fo the verticillium as the wood and bark in these plants are a bit more robust and it conceals the visible colorations and twig dieback that we can see. The vascular damage is enough to kill off the buds so they don't leaf out in spring and then the branch shuts down later. At this time, long after the buds are gone, we see the telltale signs of verticillium. My Ogon Itaya is doing great this year, but last year I did lose a little branch on the lower part of the tree as you describe. There are also some telltale signs of where dormant buds will push along the trunk in verticillium that can help us pin point the pathogen. I think the thought process is a good one you have gone through, but I will bet you and the nurseryman have been confused by one disease presenting like another. Without bud discoloration or blackening, I would look elsewhere. As for planting, certainly stress on the plant makes it more suseptible to problems like this, but the particular plant you are working with can be fussy on account of it is often "dirty" and can shut down in parts or all at once on us if it is not happy. Autum Moon is a bit better, but still not ideal in this regard.
Hi Emery- may be you could take a branch to a lab, and have it analysed. It might be worth the effort for your future plantings, if this one dies? As regards planting where you live: you know your soil, so you know best, of course. Peat and related material do have the additional problem that they break down over the course of one year, and I'm not sure they help in the long run. (I have read about 'shrunken landscapes' where the peat has broken down, and created a much denser, soggier, soil mix.) May be there are still other strategies to deal with the soil you have - one is raising the tree above grade: that way the roots might stay above the water table, plus the maple roots do stay at the surface, so if the soil above has been loosened sufficiently and in a wider circle, they might establish faster? May be other people have some more strategies and experience with heavy soil? My point about water movements was also that - and here again, someone might want to correct me - the delicate feeder roots might not 'leave' the initial rootball (or die off) because the peat around it is retaining too much water. Or they die off since the peat mix is too dry at various spots. Again, since you know your soil, may be what I am saying is not to the point. You talk about the difference between the initial media in which the tree came and your soil. If you eliminate all the initial soil (I heard that acers tolerate very well this procedure, important if you grow in containers) I'm not sure in how far the change itself (not the condition afterwards) affects the tree, is a direct contribution to the state of the tree (usually they like leaving the confines of container, if old enough). Good luck with all this. schusch (As regards other sources of maples, if you look at the top of this forum (list of websites) you get Maillot Erables: I ordered from there, they have a large and often intriguing selection, and M. Maillot is prompt in answering any questions. I also bought plants from CECE Pépinières in Bray (Binche, Belgium): M. Choteau is a dedicated grower, and might not be too far from where you live (not sure whether he sends by mail to France already: I think he is working on it, as well as on his website, http://www.cece-choteau.be/fr/index.php)
