May 10, 2019   
  Issue 2

Prepared by:

Paul Kassel

Extension Field Agronomist



(712) 262-2264




Serving Clay, Buena Vista, Dickinson, Emmet, Hancock, Kossuth, Palo Alto, Pocahontas, Sac and Winnebago Counties



The U.S. Department of Agriculture (USDA) prohibits discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion, age, disability, political beliefs, sexual orientation, and marital or family status. (Not all prohibited bases apply to all programs.) Many materials can be made available in alternative formats for ADA clients. To file a complaint of discrimination, write USDA, Office of Civil Rights, Room 326-W, Whitten Building, 14th and Independence Avenue, SW, Washington, DC 20250-9410 or call 202-720-5964.


The Iowa State University Extension and Outreach Policies Page.  


























Volatilization loss of surface applied urea, UAN.  
Surface applied urea or UAN solutions can have losses of nitrogen due to volatilization .  UAN solutions are half urea.  Incorporation by 3-4 inch deep tillage or by 0.5 inch of rainfall within two days of application will minimize surface volatilization losses.
Conditions that favor volatilization losses from urea, or UAN solutions.
-          Damp soil surface
-          Warm and sunny conditions
-          High pH soils
-          High amounts of crop residue - as in corn on corn situations.
Conditions that lessen volatilization losses from urea, or UAN solutions.
-          Dry soil surface
-          Cool air temperature
-          Neutral or slightly acid soil pH
-          Low amounts of crop residue.
Imbibitional chill injury. Injury can occur to corn seedlings when corn seeds imbibe water that is colder than 50 degrees within 24 hours of planting - which may have occurred to corn planted on May 7. Soil temps have fluctuated greatly in the past two weeks. 
Read more about imbibitional chill injury here .
ISU Custom Rate.   The most recent Custom Rate Survey in available on ISU's Ag Decision Maker website.
Crop Scouting School.   There is a Field Scouting Basics Workshop at the ISU Field Extension Education Lab near Boone from 9:30 to 3:50 on May 16.  The cost is $100 - register here by May 13.  


Prepared by Paul Kassel, Extension Field Agronomist

Phone: (712) 262-2264, Email: