Newly emerging Palmer amaranth

Travis Legleiter, Weed Science Professional Assistant, Botany & Plant Pathology, Purdue University

Palmer amaranth seedlings are beginning to emerge in Indiana after a cold hard winter. The emergence seems to be right on cue from what we saw last year (2013) at our Cass county Indiana Site. A few spares seedlings were noted the week of May 5th-9th and counts of approx. 20-25 seedlings per meter squared were noted on May 15th despite cold rainy conditions

These pictures were taken on May 15th of very freshly emerged Palmer amaranth in our Palmer amaranth emergence study at Cass County. We imagine that many of these plants had emerged in the last 24 hrs. Due to many still having their cotyledons inside the exposed hard black seed coat.

The warming weather coming next week (May 19-23rd) in combination with the well-saturated soils will very likely continue to promote palmer amaranth. We predict that our emergence counts will continue to rise in the next couple of weeks and that palmer plants will quickly become established as we approach the month of June.

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