Hello here , Firstly thank you for sharing experiences of forum members about those trees and vegetation that we love so much , this forum is full of information . I live in France and My Maple this year have suffered of rain almost permanent for almost three months and few of my maple look like to have caught powder mildew , firstly I did not worry more than that and now few one look like to got powder mildew , the first one Beni Hagoromo and beni shichihenge had a small portion of the leaves and branches with fine white powder , now I had removed leaves with white powder , I had treated with Milk without expected result so I switched to baking soda ( water ) with black soap ( or olive oil ) the result was much more effective but on the branches I had to scratch with a sponge applying baking soda product . now I have one Akadama and Iijima Sunago ( my bigger and favorite JM of the house ) who look like affected but strangely only Branches and not Leaves , on my other JM for now all this rain has more created small mold stains on some leaves and not in powder form . Now I start to worry about that it spreads on all my JM . I hoped it was limestone or where a start of moss with this rain but it look like similar to the symptoms of my Beni Hagoromo and beni shichihenge at the beginning without the affected leaves . Difficult to remove stains on the branches even by rubbing with a sponge ( as you can see much has been removed on my beni shichihenge branches , but on the other maples the result is less conclusive ) I know that the treatment with baking soda needs a temperature between 10 ( 50F ) and 20 ( 68F ) degrees celsius to be efficient ( may be this parameter is not correct !! ) If anyone can give me advice , I'll take it :-) some pictures : the first three : beni shichihenge the fourth : Arakawa six seven and eighth : Iijima Sunago
Hello . At the end of the summer the powdery mildew (oidium in french) develops on many plants and sometimes on the sheets of Maples. But I do not believe that the witish color on the branches is the same cryptogam. I don't know the english name of that natural protectress pellicule. (En français nous appelons cette couleur blanchâtre la pruine). In general the oïdium of end of summer is difficult to fight. The oïdium of spring is eliminated by pulverizing liquid sulphur which is preventive and also curative (but the instructions of use are rather strict, full morning sun and temperature 18/24°). A pulverization of copper sulfate (Bordeaux mix) has preventive effects. Now it's too late for any treatment.
Consider spraying a solution of 10ml 3% hydrogen peroxide (from the pharmacy/grocery/beauty-supply) in 1 liter of water and a couple drops of detergent. This makes a very eco-friendly, broad-spectrum fungicide + bactericide. Oxygen released from the peroxide attacks the pathogen and becomes just ordinary water. However, it only works on what is present at the time it is sprayed. In other words, it has no latent effectiveness like Bordeaux mix, lime sulfur, Daconil, etc. do.
Hello , Wow , thank you Opusoculi & Osoyoung for your quick and interesting answer . Osoyoung , your solution of Hydrogen Peroxide with Detergent look like very interesting and I really want to see the result about my problem . Today I had bought Hydrogen Peroxide 10 Volume ( 3% ) and tomorrow I'll buy Saniterpen 90 ( is a disinfectant approved for the habitat of your animals ) & look eco-friendly . Usage tips : For a bactericidal treatment, dilute the product to 0.5% (ie 5 ml per liter of water). For a fungicidal treatment dilute the product to 2% (ie 20 ml per liter of water). So I'll dilute the product to 2% to get bactericidal & fungicidal treatment ( if I understood correctly by reading you ) I hope the dilution will be safe for my JM . ( I will start on a part of one of my maples to see the reaction ) I'll let you know about the evolution and show you some pictures . Thank you again .
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