Orange spots on the honeycrisp
My Honeycrisp has some orange colored raised bumps on some of the leaves. In the book I got it describes scab, and cedar apple rust, but neither look like what it is. Book says scab is brown, and the rust is on the under side of the leaves, this is on the top. What is it?
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applestar
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Sounds like Cedar-Apple Rust to me! They start out as yellowish spots that develop into raised orange bumps with grayish undersides, followed by tentacle like fruiting bodies beneath the leaves that produce spores. I pick off affected leaves at first sign (dispose in trash) and start spraying with the Milk Solution (about 1:4 milk:water with some lactobacillus culture --plain yogurt, Sour cream, etc.).
I only have cultivars resistant to C-AR (and fireblight) -- both extremely prevalent in my area -- so those measures are sufficient. If your trees are not disease resistant, you may need to take more aggressive approach..
ETA: According to this chart. Honeycrisp is susceptible
https://www.extension.purdue.edu/extmedia/BP/BP-132-W.pdf
I only have cultivars resistant to C-AR (and fireblight) -- both extremely prevalent in my area -- so those measures are sufficient. If your trees are not disease resistant, you may need to take more aggressive approach..
ETA: According to this chart. Honeycrisp is susceptible
https://www.extension.purdue.edu/extmedia/BP/BP-132-W.pdf