apple scab

noun

: a disease of apple trees caused by a fungus (Venturia inaequalis) producing dark blotches or lesions on the leaves, fruit, and sometimes the young twigs

Examples of apple scab in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Neem oil is a natural fungicide that helps to control common apple diseases like apple scab, rust and powdery mildew. Steve Bender, Southern Living, 12 Apr. 2025 In a wet year, a disease-resistant apple tree may still show the symptoms of apple scab and powdery mildew, fungal diseases that are encouraged by high humidity and wet leaves. Beth Botts, Chicago Tribune, 16 Feb. 2025 For example, growing chives near fruit trees reduces the incidence of apple scab and repels certain types of tree borers that might otherwise do major damage to home orchards. Lauren Landers, Better Homes & Gardens, 16 Feb. 2025 These specialty crops are especially susceptible to diseases like apple scab, a fungal ailment that attacks both a tree’s leaves and fruit with unsightly lesions, and outbreaks of highly infectious fire blight, which can kill entire trees outright. Laura Kiniry, Smithsonian Magazine, 22 Dec. 2023

Word History

First Known Use

1883, in the meaning defined above

Time Traveler
The first known use of apple scab was in 1883

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Cite this Entry

“Apple scab.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/apple%20scab. Accessed 9 Sep. 2025.

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