Skip Navigation

Yellow Leaves Emerge from Twisted Whorls – 2011

By Roger Elmore, Department of Agronomy

Yellow leaves wave above V5 to V8 corn canopies in northern and central Iowa this week.   These sun-starved leaves freshly emerged from twisted whorls will turn green soon after they begin intercepting sunlight.

Potential causes are numerous:  rapid growth coupled with a wide range of temperatures, hail, strong winds or an application of a herbicide, insecticide or fungicide, etc. 

These two references describe these symptoms and causes in more detail: Twisted Whorls and Twisted whorls and ‘buggy whipped’ corn.

Yellow leaves resulting from twisted whorls associated with an application of a growth regulator herbicide. Broadleaf weeds in the photo were affected too.
  Photo by Brian Lang, ISU Extension Field Agronomist; 2011.

I would expect these plants to look almost normal within a few days to a week or so. If the malformation causes a delay in either growth or development, it could result in yield reductions. But any yield reduction would likely be hard to detect on a field basis unless the symptom is widespread.

See more images at our website Image Gallery: Crop Diagnostics, Early Season Diagnostics.  Click on the thumbnail images to see image descriptions.


Roger Elmore is a professor of agronomy with research and extension responsibilities in corn production. He can be contacted by email at or (515) 294-6655.


This article was published originally on 6/22/2011 The information contained within the article may or may not be up to date depending on when you are accessing the information.

Links to this material are strongly encouraged. This article may be republished without further permission if it is published as written and includes credit to the author, Integrated Crop Management News and Iowa State University Extension. Prior permission from the author is required if this article is republished in any other manner.