Powdery mildew?

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Waltron
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Powdery mildew?

Post by Waltron »

I'd never heard of this condition until 5 minutes ago when I read the related topic by Jamie (Thanks Jamie). I recently noticed white powdery blotches on the leaves of a 1 year old birch cutting I have growing in the ground, I haven't even looked at this plant for a month or two so I don't know how long it's been like this.

So, is this powdery mildew?
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Re: Powdery mildew?

Post by Jamie »

it looks a bit like it mate, this will be good linked on to the other topic, it is generally caused by excess moisture from water at night.

refer to my other post in pests and diseases on how to fix it.

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Re: Powdery mildew?

Post by Waltron »

In the other post you mention "Remove and destroy all infected plant parts", in this case that would mean a complete defoliation, will this kill it?
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Re: Powdery mildew?

Post by Jamie »

hmm thats a good question, you say its a one year old cutting correct? how big of a cutting was it? if it had some size it should have enough stored energy to come back from the defoliation, other wise if it doesnt have many leaves and it is still small wipe the mildew off with a damp cloth early in the morning and hopefully it will the leaves will be free of moisture before the sun hits it, and be wary when watering the tree as to just water the base and not the whole tree.

doing it this way should at least get rid of the prob with out defoliating the tree, although it isnt far off autumn and they will be dropping soon anyways, but to defoliate now means the tree might try and push new growth into autumn and it will suffer die back :?

i would just try the wipe off method, it has worked for me before :D the removal of the infected leaves and destruction of them was recommended on various websites, but you are in a bit of a predicament with it being youngish.

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Re: Powdery mildew?

Post by stymie »

Waltron, Hi buddy.
Spray the infected leaves with milk. That controls the mildew without harming the tree and may be repeated at ten day intervals if necessary.
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Re: Powdery mildew?

Post by Jamie »

stymie wrote:Waltron, Hi buddy.
Spray the infected leaves with milk. That controls the mildew without harming the tree and may be repeated at ten day intervals if necessary.

undoubtably you have experience in this don, but i have a question- wouldnt milk go off and become mouldy in itself? or does it get flushed out with constant watering?


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Re: Powdery mildew?

Post by Ron »

stymie wrote:Waltron, Hi buddy.
Spray the infected leaves with milk. That controls the mildew without harming the tree and may be repeated at ten day intervals if necessary.
I took some small English oak trees down to Ray Nesci yesterday that had powdery mildew on them and this was his advice too - 1 part full cream milk to 8 parts water sprayed on.

And to keep them in a sunny spot and spaced away from other plants so that they get plenty of room around them for air circulation.
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Re: Powdery mildew?

Post by Waltron »

Thanks guys,

Yes, I have been reading up on this condition and a diluted milk solution is common advise. Seems there has actually been positive studies done on this too, I read somewhere last night that it won't matter whether full cream or skim milk is used, though you'll only find full cream milk in my household... The Birch gets about 8 hours sun a day and seems to me to be in an open enough position. I'll try the milk idea until the tree defoliates itself in autumn.

Cheers.
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Re: Powdery mildew?

Post by Waltron »

It seems like the diluted milk solution has done the trick, the leaves have completely cleared up after 3 applications; 1 per week. The only side effect being wasps - and plenty of 'em, they like milk! :)
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Re: Powdery mildew?

Post by tex048 »

Hi and thanks to eveyones posts in this thread.

Once again i had a question and found the answer.

GO AUSBONSAI ..

For the first time ever I have noticed powdery mildew on my oaks, I think a mixture of lot of wet days and nights, and the sun not fulling coming unto our backyard just yet.

Just wiped down leaves and sprayed with milk mixture, will wait and see.

Thanks team
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Re: Powdery mildew?

Post by NBPCA »

tex048 wrote:Hi and thanks to eveyones posts in this thread.

Once again i had a question and found the answer.

GO AUSBONSAI ..

For the first time ever I have noticed powdery mildew on my oaks, I think a mixture of lot of wet days and nights, and the sun not fulling coming unto our backyard just yet.

Just wiped down leaves and sprayed with milk mixture, will wait and see.

Thanks team
Pest oil also seems to keep powdery midew at bay.

Grant
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