May 28, 2009

 

CORN

 

Black Cutworms

 

I am receiving scattered reports of minor black cutworm injury in areas south of Highway 30.  If eggs were laid during the late April moth flight, feeding should begin along Highway 30 today.  Based on the National Weather Service temperature forecast, the onset of any cutting along Highway 20 should occur on Saturday May 30 or Sunday, May 31.  Scouting should always begin a couple of days prior to the projected onset of cutting and continue until the corn has reached V5 (the five-leaf growth stage).  For information on scouting for and management of black cutworms, see http://www.extension.iastate.edu/Pages/eccrops/blackcutworm.html.

 

Stalk Borers

 

Most commonly, stalk borers hatch in ditches, fence lines, and waterways, where they move into tall grass, such as brome. As the stalk borers develop, they outgrow the grass plant, killing the top of the plant, and they then move into nearby crop land, generally corn.  As each dead stem represents one stalk borer that may migrate into the field, observing the seed head stems of tall grasses for signs that they have been killed will provide some guidance on the need to spray the edge rows of corn to kill the stalk borers as they migrate into the field.

 

Stalk borer migration from grassy areas into adjacent corn rows should begin Friday, May 29 along Highway 34.  Using National Weather Service Temperature forecasts through June 2, 2009 and then normal temperatures thereafter, migration should begin along Interstate 80 on Friday, June 5, along Highway 30 on Tuesday June 9, and along Highway 20 on Saturday, June 13.  Weather anomalies between now and then may change that.

 

To monitor Growing Degree Days for stalk borers and for more information on managing stalk borers, see http://www.extension.iastate.edu/Pages/eccrops/stalkborer.html.

 

 

Late Spring Soil Nitrate Test

 

Late Spring Soil Nitrate Test samples should be pulled to a one foot depth when the corn is 6-12” tall at the whorl. Soil samples should be sent to a lab immediately after sampling. Results can help to fine-tune nitrogen management.

 

It is best to use a systematic method rather than a random method to pull the samples. Pull the first sample in the corn row, the next 1/8 of the distance between rows, the next ¼ the distance between rows, etc. until you have worked your way across the rows. Do this at least twice for a total of 16 cores. This way you won’t by chance happen to be over or under representing areas that have differing amounts of nitrogen (i.e., anhydrous bands, manure bands, starter fertilizer, etc.).

 

For more details see the publication “Nitrogen Fertilizer Recommendations for Corn in Iowa” at http://www.extension.iastate.edu/Publications/PM1714.pdf.

 

 

FOR YOUR CALENDAR

 

SPRING FIELD DAY & SPECIAL SESSION FOR CCAs

SE IA RESEARCH FARM – CRAWFORDSVILLE

JUNE 24

 

Certified Crop Advisors can obtain 5 hours of credit (including 3.5 hours in soil and water management) by attending a residue management training workshop in the morning followed by the afternoon tour at the ISU SE Iowa Research & Demonstration Farm near Crawfordsville on June 24. There is a $50 fee ($70 after June 22) for CCAs attending for credit. Non CCAs can attend the morning residue management training workshop for $10 (which includes lunch). There is no charge for the afternoon field day except a $5 fee for those wanting lunch at noon. Fees (check or cash) can be paid at the door, but if you plan to attend the morning session or want to reserve a lunch at noon, please send Jim Fawcett (fawcett@iastate.edu) a note by June 22.

 

8:30 a.m. – Noon         Residue Management Training Workshop (targeted at Certified Crop Advisors)

 

Ø Residue/Soil Carbon/Nutrient Cycling          

Mahdi Al-Kaisi, ISU Extension Agronomist – Soils

 

Ø Cover Crops, Erosion, and N-leaching

     Tom Kaspar, Plant Physiologist, National Soil Tilth Lab

 

Ø What is the Value of Soil & Crop Residue?

Andy Herringshaw, Graduate Research Assistant, Sustainable Ag - Economics

 

 

Noon                             Lunch ($5 for those not attending the morning session.  Reservations required by June 22.) 

 

 

1:00 p.m. – 3:00 p.m.  Spring Field Day Tour (for everyone)

 

Ø Crop Season Review & Current Crop Concerns

Kevin Van Dee, Farm Superintendent, & Jim Fawcett, ISU Extension Field Agronomist

 

Ø Monitoring Yield Data for the ACRE Program

Jim Jensen, ISU Extension Farm Management Specialist

 

Ø Cover Crops for Soil Conservation & Better Soils

Tom Kaspar, Plant Physiologist, National Soil Tilth Lab

 

Ø Corn & Soybean Fungicide Research Results

Alison Robertson, ISU Extension Plant Pathologist

                              OR

Ø Organic Crop Opportunities

Kathleen Delate, ISU Extension Organic Specialist

 

 

Advances in Precision Ag Field Day

ISU SE Iowa Research & Demonstration Farm – Crawfordsville

September 17

 

See the latest in precision agriculture technology, including RTK guidance systems, auto-steer, automatic shut-off planters, and sprayers. As details emerge, they will be posted at  http://www.extension.iastate.edu/Pages/eccrops/meetserc.html.