Hi, My paperbark maple tree has some kind of disease and im having trouble figuring out what it is. The tree is planted in a soil called "Rhododendron soil" its a very open soil wich much organic material and its quite acidic. The tree has had no shortage of water, maybe i've been prone to over water it. Ive tried some googeling and cant come to any conclusions my self but have two main theories. iron chlorosis which could be explained by the choice of soild which i think is lacking in iron and the fact that i've might been over watering the tree. The second option ive concluded is Verticillium wilt, which ive understood i should hope its not. The symptoms has affected the whole tree and about half of the leafes has fallen of and more falling daily. No part of the tree is unaffected. Many thanks and hoping for some guidance, /David
Hi, welcome to the forum. Maybe a form of anthracnose ?... (Anthracnose [Trees and Shrubs] (Many genus and species involved)-Hort Answers - University of Illinois Extension) Before more savvy experts can give you their diagnosis, I found this page that you might find interesting to read : Soil Requirements of the Acer Griseum Excerpt : "Although pH considerations aren't vital the the plant's survival, the paperbark maple prefers alkaline or only slightly acidic soils."
Hi, Thank you, and many thanks for your reply. I bit irritating since it was the information i came with to both the seller of the tree and the supplier of the soil which both recommended the soil its planted in. And im no expert so i listened to their advice. However reading along it seemes the tree should adapt and shouldnt be too affected if it was healthy otherwise? Any suggestions on how i would go about with increasing the alkalinity? Thought about using ash from a woodstove (birch) as additive. Or should i blend in some regular alkaline planting soil?
Hi David, Sorry you're having troubles with your Paperbark. For sure, griseum doesn't like too much acid, but as you say, they can get along with it, too. We are at 4.8-5.2, depending on the spot, and griseum grows well here. My observation is that they seem to like garden soil much better than custom substrate. They almost always seem to do better out of the pot: our latest, a variegated cultivar called 'Golden Lucky', sulked for years in a pot. Once in the ground, growing fine. (Whether it's variegated or not is another question). I think your soil is holding too much water, which is encouraging the leaf spot, chlorosis, and -- this is the real giveaway -- the leaves bent over the petioles. That last is a very sure sign of over watering, but it could just be the pot is too big, or the substrate not draining enough, or water not getting out of the pot, whatever. The nursery and soil company marketed you a bag of soil you didn't need, and that is sub-optimal for the tree. Nurseries often promote this old myth of "Ericaceous Soil" here too, it adds to profit margins. Amending it is a mug's game, because a) hard to do and b) not the problem anyway. I've been assuming it's in a pot; if you dug a hole, filled it with the compost to plant in, that's even worse for it as it makes a sort of a bowl that water can't drain from. In this case, just plant in your native soil, that will be best for it. Good luck, -E
I always order 2 (or 3) when I order online. One of them died in the first winter -- wanted to see if it could make a bonsai and probably pruned the roots too heavily. The other one is now about 1,70 metres tall and the bark peels off in summer. The soil in the pot is about 50% garden centre compost, 25% pozzolan (5-7 mmm) and 25 % composted pine bark. It gets the sun from 4 to sunset. I also have an Acer triflorum, very close to it, but the bark is not as "spectacualré", and on mine the leaves are of a lighter green I also stratified then planted in a tray about 80 seeds of Acer mandschuricum from a very reliable provider, another of the "trifoliate kind", but none of them germinated. I've kept the tray and water it like all my trees/seedlings. Out of 80, maybe one will sprout next spring ?... ;°)
