On an apple tree - scab or something else?
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Looks just like cracks in bark from rapid growth basically harmless.
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I planted a grape in April and it is thriving BUT I think it has downy mildew. This is my first time with grapes. Can someone confirm if this is indeed downy mildew? Since my grapes won’t be fruiting this year, would you suggest I still spray it? Besides removing leaves, there’s no way to improve airflow (it’s on a single pole and there’s nothing in an 8 foot radius or so)
My other grape seems to have a different disease. Ignore the white powder- that’s baking soda . It’s been hot and humid recently so I figured they’d catch something.
If it was on mine I’d say the second and third picture are Japanese beetle damage.
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I’m going to second the vote on Japanese beetle damage, which I already expect because it’s a grape.
Japanese beetles were first sighted this year in the Minneapolis area on July 4 or so.
Things were a lot worse and prior years but there is a parasitic wasp that was released by the state and my trap shows about 1/3 of the Japanese beetle so far were struck by the wasp. They have anywhere from one to four white dots on their backs.
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I saw a Japanese beetle the other day on my raspberries nearby so it’s probably true. The picture from the IPM app does look exactly like their bite marks. I hope the birds learn to love to eat the beetles and not the grapes. Thank you both!
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Unsure if a good thing or bad thing but the very next day after a baking soda application the leaves have changed color. So it did something, I just hope it was positive
@zone7a
So you can just sprinkle the baking powder on? I always thought you would have to dissolve stuff like that in water and make a spray.
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I only have two grapes which needed this so it wasn’t hard to give them TLC by hand rubbing on the baking soda instead of a spray. I put a bunch in a small jar and just rubbed some on. A bunch did come off (and that may be bad for salts etc) but you could also probably make a thick paste too and smear some on.
My guesses: putting a pure powder like I did won’t stick as easily EXCEPT my leaves were a little wet from recent rain anyway.
Pure powder will be more concentrated and therefore will act faster than a spray, but it may be less effective because it’ll be less sticky or even too concentrated. There may be a significant amount of powder that will land in the soil.
I need to look more into it, but the leaves turning a different color the next morning makes me hypothesize the mildew is dying because of the baking soda, but it could just be leaf burn! (But imo it doesn’t look like leaf burn)
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