Corn plants in rapid growth phase showing wrapping of leaves at the whorl. Affected plants typically recover and resume normal growth.
Leaves that have been trapped in the whorl will often be bright yellow when
they emerge, making them very noticeable in the field.
Elmore, R. and M. Licht. 2012. Twisted Whorls and Yellow Leaves. Iowa State Univ.
Nielsen, R.L. 2011. Wrapped and Twisted Whorls in Corn. Purdue Univ.