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Mind the moldy dust during harvest

By Angie Peltier and Liz Stahl, Extension educators - crops Photo: Dave Nicolai Saprophyte – this is a fancy term for fungi that make their living by colonizing and extracting nutrients from dead tissue. Saprophytes are the reason continuous corn fields aren’t packed with piles of corn residue taller than us – saprophytic fungi help to degrade dead tissue as they complete their own life cycles. In years where we have rain after the corn crop has matured, but before the crop is harvested, saprophytic fungi are able to colonize and begin degrading corn tissue. The dark-colored dust that has been trailing combines in southern MN this year is most likely spores of saprophytic fungi that are helping to decay corn residue. When you are out 'push-testing' your crop, the mold can even work its way through your clothing and cover your face ( Figure ). Figure. The author covered in a 'mold beard'. Note: the shirt has gone through a heavy-duty wash cycle twice and still
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