Irrigation Update 7-7-2021

What a change a couple weeks of rain can make…Rains over the last 3 week have refilled the water holding capacity for most fields. Expect producers to start irrigating when the accumulated rainfall deficit from the crop water removal after subtracting the rainfall totals is 1.5 -2.5” of soil moisture reserve. Irrigators with irrigation capacity less than crop removal should start sooner than irrigators with adequate irrigation capacity allowing them to drain the water reserve down for a few days before starting.

With a predicted Ref ET of 1.4” for the week, the water use by corn at V-10 is 1.1” and V-14 is 1.5” for the week. Soybeans water use at V-3 will use 0.9”water and soybean approaching R-1 will use 1.4” For more information on Irrigation scheduling see:

I have had several questions about replacing N loss to heavy rains or adding N where side dress was missed or inadequate. Fertigation is an excellent way to add N when needed but is limited to only the irrigated section of the field and at least enough water removal since the last soil profile filling rain to allow for the fertigation application to be held in the root zone. For more information:

Fungicides through irrigation (Chemigation) many producers are planning to apply fungicide through irrigation center pivots during mid to late July and beyond. Please help make sure adequate backflow protection is in place and the producers are aware of the chemigation label requirements. Please look for “Chemigation –short narrated” as a power, point for more info.

Please help me advertise a Six Session Irrigation webinar series that starts Tuesday (July 7 from 12-1:00 pm.)

Each session will have a presentation on:

  • Irrigated crops Management, ( Dr. Camberato is talking on mid-season irrigated corn N fertilization decisions tomorrow)
  • A presentation for new or prospective new irrigators
  • An irrigation update from one of the many crop industry dependent on irrigation.
  • An irrigation related question and answer time – please forward irrigation related questions to me.

The registration site below will get producer to future irrigation webinars in the series and to recording of past webinars. Event Summary for Irrigation Webinar Series | ANR Events Management System (

Water… it there to use but not abuse…

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