Tar spot, prussic acid concerns rise this fall

By Sara Bauder, SDSU Extension
Oct 4, 2024
Oct 4, 2024

Sow and Grow tar spot 1.jpg — Tar spot of corn is spotted in South Dakota. This plant disease appears as black, circular to diamond shaped lesions that vary in size. Lesions are visible on both sides of the leaf.
Submitted photo by Ciera Kotaska

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By Sara Bauder, SDSU Extension

The South Dakota State University plant pathology team identified tar spot on corn in 44 counties across eastern South Dakota as of Oct. 2.

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Sow and Grow tar spot 2.jpg — *Tar spot of corn is spotted in South Dakota. This plant disease appears as black, circular to diamond shaped lesions that vary in size. Lesions are visible on both sides of the leaf.*
Submitted photo by Ciera Kotaska

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Sara Bauder is forage field specialist for South Dakota State University Extension, based at the Mitchell Regional Center. Reach her at 605-995-7378 or sara.bauder@sdstate.edu.