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Warm temperatures continue in Illinois, with growing degree day (GDD) accumulations since May 1 running from 150 above average in northern Illinois to about 250 GDD above average in the rest of the state. With GDD accumulations of 900 to 1,000 since May 1, the corn crop planted in early May is at V10 to V14, about 30 to 60 inches tall, and needing only about 350 to 450 more GDD to tassel and silking. With daily accumulations at about 25 GDD,…

We worried our way through the cool month of April, with 32 percent of corn and only 7 percent of soybean acres planted by April 29, and nothing emerged. During the first two weeks of May, the weather was warmer and drier than normal, and adding together corn and soybeans, Illinois farmers planted more than a million acres for each of the 10.3 “days suitable for fieldwork” between April 29 and May 13.
By May 13,…

Parts of Illinois received some precipitation for the third Sunday in a row (starting with Easter) on April 15, and in a few places, also for the third Sunday in a row, it came partly in the form of snow. That streak should end this weekend, and less rain and warmer temperatures are predicted to move in for the rest of April.
Some ammonia went on late last week and there was planting activity in places,…

Last month (March 2018) we used data from 2017 N rate response trials to update the N rate calculator that provides best-estimate N rate guidelines for different regions and previous crops (corn or soybean) in Illinois. The updating process, which is currently being done by spring each year in Illinois, involves adding the new data and taking out some of the older data.
Many people understand the idea of using data from previous research to try to predict how a management factor will work the next time (in this case,…

If the old saying that rain on Easter means that it will rain on the next seven Sundays applies to snow, we’re in trouble – it snowed across a wide swath of Illinois on Easter Sunday (April 1) and also on April 8.
We had enough dry weather in March to allow some ammonia to go on early, but there has been little opportunity for field work over the last six weeks. Rainfall over the past month has been below normal for the northern third of Illinois and above-normal in the southern half of the state,…

I wrote a short article here about a month ago asking for everyone’s cooperation on a project in which we (Corn Belt states) are gathering field-level information on soybean fields to feed into a study, funded (with soybean checkoff dollars) by the North Central Soybean Research Program, looking at weather, soil, and management effects soybean yield over the Corn Belt.
While we got some response to that article, we have so far gathered information on less than half the fields in Illinois that we,…

The substantial rain that fell over central and northern Illinois between October 5 and 15 mostly soaked into the soil that was dried out by crop water use, and harvest has moved back to full speed in most areas. With harvest, thoughts turn to application of fall ammonia in central and northern Illinois. Almost everyone is on board with waiting until soil temperatures are at or below 50 degrees before applying ammonia. Cool soil (along with use of nitrification inhibitor) lowers the rate of nitrification,…

A group of people who work on nitrogen fertilizer met in 2004 to talk about an alternative to the yield-goal-based N recommendation system that had been in widespread use for some three decades. The main concern with the yield-goal-based system was that, as corn yields increased over time, N rate trials were showing that the amount of fertilizer N needed to maximize yields was not going up as fast as yields. On the other hand, the amount of fertilizer N needed on lighter soils,…