I have been trying to grow Amur maple seedlings for three years as singles, clumps, and forests. Every year I am haunted by what I would assume as fungus...black edges on leaves which usually ends up eating all the leaves on the tree. Then they start over again and here come the black leaf edges again. I have sprayed at least three times this year starting early but have them again this year. Yes all my maples are in my storage shed in the winters where the humidity is higher, but I have a fan running. I know these things are tough and maybe I should just leave outside in my 5-6 zone and I would not have the problem. The fungus only seems to attack the Amur and not other maples in the same shed. Are Amur's just more susceptical than others. Drives me crazy! Help appreciated.
Amur maple and fungus
- Thread starter August44
- Start date
Mike Corazzi
Masterpiece
Isn't "Oregon, storage shed, higher humidity" sort of a travel brochure for fungus?
Eckhoffw
Masterpiece
Interesting. That’s a real pain in the rump!
I think your thought of leaving them outside is spot on. I just started some Amurs 2 yrs ago. They stay outside in the winter bunker. So far the past 2 Minnesota winters have not phased them.
I think your thought of leaving them outside is spot on. I just started some Amurs 2 yrs ago. They stay outside in the winter bunker. So far the past 2 Minnesota winters have not phased them.
Forsoothe!
Imperial Masterpiece
Ya know this is also called Siberian Maple? You are in Rain Capital of North America, The Pacific Northwest. Keep the panzy-ass Maples in the shed, but the real men of Mapledom want to winter outdoors.
0soyoung
Imperial Masterpiece
Amur maples are USDA zone 3 cold hardy. Leave it/them outside!
Do remember that cold hardiness is induced by being exposed to several cycles of deepening cold that naturally happens in fall. Lacking this, Amur maples (and any plant for that matter) are far less hardy.
Most spray fungicides work by leaving a residue that is activated when it is wetted (by rain, is the expectation). Of course this also washes the fungicide from the plant. IOW, one should avoid wetting the foliage when watering and should re-spray after a rainstorm or having accidentally sprinkled the plant.
Do remember that cold hardiness is induced by being exposed to several cycles of deepening cold that naturally happens in fall. Lacking this, Amur maples (and any plant for that matter) are far less hardy.
Most spray fungicides work by leaving a residue that is activated when it is wetted (by rain, is the expectation). Of course this also washes the fungicide from the plant. IOW, one should avoid wetting the foliage when watering and should re-spray after a rainstorm or having accidentally sprinkled the plant.
bwaynef
Masterpiece
I have a Field maple (A. campestre) from Oregon and an Amur maple (A. ginnala) that behaved exactly as you described for the past 3 years. This spring, neither have had the first inkling of an issue and are growing with the vigor I've only heard about, but never witnessed.
2 things changed: I removed an oak canopy and situated my trees where they get a TON more light and I dormant sprayed w/ oil and lime sulfur (2 separate applications 4-5 weeks apart). I attribute the lack of dieback to the dormant sprays, ...but the additional light could be playing more of a part than I suspect. There isn't a great way for me to tell for this year. I'll say, its a LOT cheaper to spray oils than have ~15 mature oaks removed.
2 things changed: I removed an oak canopy and situated my trees where they get a TON more light and I dormant sprayed w/ oil and lime sulfur (2 separate applications 4-5 weeks apart). I attribute the lack of dieback to the dormant sprays, ...but the additional light could be playing more of a part than I suspect. There isn't a great way for me to tell for this year. I'll say, its a LOT cheaper to spray oils than have ~15 mature oaks removed.
sorce
Nonsense Rascal
Not if you just light a match and give a warning! Lol!
@Peter44 I'll snag a amur seedling of mine and send it to you, they're gangster!
As the biggest advocate for "f the shed", I still don't see how that would have any effect on these maples. Less you blow hot farts in there and seal it in spring!
Pics!
Sorce
Enfield Snapper
Mame
It depends on which part of the state you're in. Much of the state doesn't get the crazy rainfall you see near the coast. Portland (not even the wettest part of the state) gets nearly triple the annual rainfall of Baker City, for example. Oregon and Washington both have areas classified as semi-arid desert. So the Pacific Northwest is not a universally soggy region.
Have you ever looked at Oregon and Washington on Google maps with the satellite layer turned on? Most of that area is brown.
Mike Corazzi
Masterpiece
I agree with all that you are saying here. I will never shed them again. Just so you understand Oregon...I live on the East side of Oregon, the would be East of the Cascade Mts. The weather (and the politics) are very different here than the West side. Portland, Or ( the West side) gets 43" of rain per year and in growing zone 7-8 I believe. Baker City, Oregon, where I live is in zone 5-6 and we get 15" of rain with very low humidity. We can have some pretty severe winters with -20, snow and winds. I do have maples other than Amur that don't seem to be affected like the Amur, but I am going to phase out maples I think. I just joined the Boise Bonsai Society (2 hrs away) so maybe I'll be able to get some good hands on and feel better about bonsai. There are some really great people in that club! Thanks for all the answers and help!
Eckhoffw
Masterpiece
Sounds good. let’s see how that goes. excited to b able to go back to regular bonsai club meetings soon !
