July 19, 2017 Weekly Crop & Weather Update

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Below you will find the daily maximum and minimum air temperatures, growing degree units (GDUs), and 24-hour precipitation amounts for this week. These values are recorded at 8 AM and reflect the conditions for the previous 24-hour period (8 AM to 8 AM) at the Southern Research & Outreach Center, Waseca.

Date Max Air Temp (oF) Min Air Temp (oF) GDUs Precip (inches)
Thursday, 7/13 86 60 23.0 -
Friday, 7/14 72 61 16.5 -
Saturday, 7/15 75 60 17.5 -
Sunday, 7/16 92 65 25.5 -
Monday, 7/17 87 66 26.0 -
Tuesday, 7/18 89 69 27.5 -
Wednesday, 7/19 90 66 26.0 -

Good corn growing weather settled into South Central Minnesota this week.  Temperature averaged 74.1 degrees or 1.8 degrees warmer than normal.  No rainfall was measured; normal rainfall amount this week would be 0.97 inch.  Growing degree units (GDUs) totaled 162 which is 6% more than normal.  Since May 1 we have now accumulated 1324 GDUs.  This is 4% more than normal. 

Last year this week was cooler and wetter.  Temperature averaged 70.9 degrees and rainfall totaled 1.95 inches.  Last year at this time we had accumulated 1356 GDUs. 

Corn is beginning to tassel and we have not seen moisture stress yet.  This should indicate that good pollination should occur and yield potential remains high at this time.  Soybean growth was also good this week and rows are now filled in completely.  I have yet to find aphids on soybeans.  Some in the area have been found, but I have not heard of any populations reaching treatment levels.  It is probably wise to not treat aphids too early and let beneficial insects keep populations low.  When the aphid predators can no longer keep up then it is time to consider treatment. 

Soil moisture measurements at SROC indicate that soil moisture at the 24 and 39-inch depth has not gone down yet this season.  Shallower measurements go up and down with rainfall or crop use.  There appears to be adequate soil moisture that corn can reach to get through pollination.