Jim Schwartz, CCA 
ICORN IGRONOMIST
1-800-240-0101
jschwartz@icorn.com

How much Nitrogen have I lost?

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How much Nitrogen have I lost?

Well, it appears that everything old is new again.  Back in the spring of 2001 I wrote an igronomist report detailing nitrogen loss in a wet spring like this one.  Take a look at the article, I hope it helps.  I have also included a link to a recent release from Purdue that covers the same topic but not in quite as much detail.  The bottom line is that, if there is one positive to the cooler temperatures, the conversion of ammonium form N to the nitrate form NO3- (the form most commonly associated with N loss) has been slow.  Also, the conversion of NH+ (ammonium N) to NO2- (nitrite) will not occur in an oxygen depleted environment since this is an aerobic process.  Nitrite is quickly converted to Nitrate which can be lost.  Therefore, the wet oxygen depleted soils may slow recently applied NH+ from being converted to Nitrate which could be lost through leaching and or denitrification.  Most of you have in all likelihood lost less N than you suspect. Check out the following links for more information.

Having gone from scary dry to soppy wet

Soggy Soils Lead to Questions About Supplemental Nitrogen Fertilizer

Weed control in a wet spring

Many growers are grappling with fields that have been planted but not sprayed and how to handle that situation.  I am not a herbicide expert, mainly because the options grow faster than I can keep up with them.  Here are a couple of good links from the Universities that might help.


Purdue Pest and Crop Newsletter

Applying Preemergence Herbicides to Emerged Corn - Loux CORN Questions

Weed Management Considerations in Corn in a Wet Spring

Be gentle with that young corn

Some day this cold wet weather will end, but until then keep in mind that those young corn seedlings are under a lot of stress.  I have recently looked at some fields suffering herbicide injury.  It is not the herbicide’s fault, but rather a combination of many environmental factors.  Most herbicides must be metabolized by the corn plant to render them nontoxic.  Metabolization is a biological process and is driven by the plant as it grows.  Well, with weather like this, very little or very slow growth is occurring and thus the plant’s ability to metabolize the herbicide is greatly inhibited, so sometimes injury begins to show.  Many times these symptoms will go away once the weather turns and the plant begins to actively grow.  Until that time, do not do anything to add additional stress to the plant such as post herbicide applications, especially products like 2,4-D and Dicamba.