April 11th marks the first day for corn planting in SW Iowa for crop insurance. With the corn planting season starting we often begin the season with optimism. While soil conditions have dried the past twp weeks soil temperatures have been slow to warm. The forecast for the next few days has us working in the shop, wearing stocking caps or waiting for warmer days to work on machinery outside. For those who want to check current soil temperatures and previous days refer www.mesonet.agron.iastate.edu/agclimate/soilt.php Below is a graph of the soil temp daily variation at the 4" level at the Armstrong Research farm. feel free to build your own graph on the site. You can adjust the location closest to your farm and can develop a map after corn has been planted to monitor predicted emergence. With dry soil conditions presently i see corn planters rolling so be sure to monitor corn emergence. With soil temperatures below 50 degrees farmers can expect slow emergence and potential for chilling inhibition. Monitor early planted fields closely if you are planting in cold soils. Soil temps in corn stalks worked with a vertical tillage tool were 41.8 degrees this morning.
Herbicide applications
With cold temperatures the past few nights herbicide applications have been difficult and can be less effective when temperatures dip below 40 degrees. Most herbicide labels will indicate to apply when weeds are actively growing. Most winter annuals and early germinating weeds are adapted to cool temperatures, however we need to understand it will take time after a frost to recover and resume more normal growth habits. It typically is best to wait 24 to 48 hours after a frost to resume herbicide applications. This is a proceed at your own risk option. If you do find yourself applying in less than good conditions you may need to increase the rate 10 to 20 percent. You may also experience inconstant results on larger weeds and an extremely slow killing conditions. This is one of those agronomic issues where patience now can pay big dividends later and provide peace of mind. As always refer to the herbicide label and talk it over with your retailer before making applications. For all herbicide labels check out the following website for information. http://www.cdms.net/Label-Database
Aaron Saeugling
Extension Field Agronomist
Office 712-769 2650
Mobile 641-344-5704
Email: clonz5@iastate.edu
Serving
Adair, Adams,Cass, Clarke, Decatur, Fremont, Madison, Mills, Montgomery, Page, Pottawattamie, Ringgold, Taylor, And Union Counties. Events
LAST CHANCE PRIVATE PESTICIDE APPLICATOR CLASS
Summer Field Day Schedules
If you missed your Private pesticide applicator class a few counties in SW Iowa will offer a one time opportunity.
Contact your Local County Extension Office ASAP
Western Iowa No-Till Field Day June 21, 2016 Shelby, IA
