Nitrogen watch archive
This page archives tracked spring rainfall and identified ‘danger areas’ that could have caused problems with N loss and deficiency in corn. This is a serious production and environmental problem that is estimated to have cost Midwestern corn producers 2 billion bushels total from 2008 to 2011.
To see current nitrogen watch content, visit nitrogen watch.
Nitrogen watch archive
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Nitrogen watch 2020
Well- and moderately well-drained soils Poorly- and somewhat poorly-drained soils July 01 (PDF) July 01 (PDF) June 23 (PDF) June 23 (PDF) June 16 (PDF) June 16 (PDF) June 10 (PDF) June 10 (PDF) June 2 (PDF) June 2 (PDF) May 26 (PDF) May 26 (PDF) May 19 (PDF) May 19 (PDF) May 12 (PDF) May 12 (PDF) May 5 (PDF) - Show/Hide
Nitrogen watch 2019
Nitrogen watch for well- and moderately well-drained soils
Well-drained soils are vulnerable mainly to nitrogen loss from leaching. This process can start shortly after fertilizer application (with some delay for ammonia). We have used April 1 to represent a preplant N application date. For ammonia or for applications later than April 1, risk is lower; for applications before April 1, risk is higher.
Areas with diagonal shading are ‘danger areas’ that are on track to have 16 or more inches of rainfall from April 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 16 or more inches of rainfall since April 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Satellite images or canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
June 30 June 23 June 16 June 9 June 2 May 26 May 19 Nitrogen watch for poorly- and somewhat poorly-drained soils
Poorly-drained soils lose N mainly by denitrification, which is very temperature-sensitive. My rule of thumb is that wet conditions in May and June cause denitrification losses, but losses in April are minimal.
Areas with diagonal shading are ‘danger areas’ that are on track to have 12 or more inches of rainfall from May 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 12 or more inches of rainfall since May 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Satellite images or canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
June 30 June 23 June 16 June 9 June 2 May 26 May 19 - Show/Hide
Nitrogen watch 2018
Well-and moderately well-drained soils
Well-drained soils are vulnerable mainly to nitrogen loss from leaching. This process can start shortly after fertilizer application (with some delay for ammonia). We have used April 1 to represent a preplant N application date. For ammonia or for applications later than April 1, risk is lower; for applications before April 1, risk is higher.
Areas with diagonal shading are ‘danger areas’ that are on track to have 16 or more inches of rainfall from April 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 16 or more inches of rainfall since April 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Midwest July 1 June 24 June 17 June 10 June 3 May 27 May 20 May 13 May 6 April 29 April 22 Poorly- and somewhat poorly-drained soils
Poorly-drained soils lose N mainly by denitrification, which is very temperature-sensitive. My rule of thumb is that wet conditions in May and June cause denitrification losses, but losses in April are minimal.
Areas with diagonal shading are ‘danger areas’ that are on track to have 12 or more inches of rainfall from May 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 12 or more inches of rainfall since May 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Midwest July 1 June 24 June 17 June 10 June 3 May 27 May 20 May 13 May 6 - Show/Hide
Nitrogen watch 2017
Well-and moderately well-drained soils
Well-drained soils are vulnerable mainly to nitrogen loss from leaching. This process can start shortly after fertilizer application (with some delay for ammonia). We have used April 1 to represent a preplant N application date. For ammonia or for applications later than April 1, risk is lower; for applications before April 1, risk is higher.
Areas with diagonal shading are ‘danger areas’ that are on track to have 16 or more inches of rainfall from April 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 16 or more inches of rainfall since April 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA July 2 July 2 July 2 June 25 June 25 June 25 June 18 June 18 June 18 June 11 June 11 June 11 June 4 June 4 June 4 May 28 May 28 May 28 May 21 May 21 May 21 May 14 May 14 May 14 May 7 May 7 May 7 April 30 April 30 April 30 April 23 April 23 April 23 April 16 April 16 April 16 April 9 April 9 April 9 Poorly- and somewhat poorly-drained soils
Poorly-drained soils lose N mainly by denitrification, which is very temperature-sensitive. My rule of thumb is that wet conditions in May and June cause denitrification losses, but losses in April are minimal.
Areas with diagonal shading are ‘danger areas’ that are on track to have 12 or more inches of rainfall from May 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 12 or more inches of rainfall since May 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA July 2 July 2 July 2 June 25 June 25 June 25 June 18 June 18 June 18 June 11 June 11 June 11 June 4 June 4 June 4 May 28 May 28 May 28 May 21 May 21 May 21 May 14 May 14 May 14 May 7 May 7 May 7 - Show/Hide
Nitrogen watch 2016
Well-and moderately well-drained soils
Well-drained soils are vulnerable mainly to nitrogen loss from leaching. This process can start shortly after fertilizer application (with some delay for ammonia). We have used April 1 to represent a preplant N application date. For ammonia or for applications later than April 1, risk is lower; for applications before April 1, risk is higher.
Areas with diagonal shading are ‘danger areas’ that are on track to have 16 or more inches of rainfall from April 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 16 or more inches of rainfall since April 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA July 3 July 3 July 3 June 26 June 26 June 26 June 19 June 19 June 19 June 12 June 12 June 12 June 5 June 5 June 5 May 29 May 29 May 29 May 22 May 22 May 22 May 15 May 15 May 15 May 8 May 8 May 8 Poorly- and somewhat poorly-drained soils
Poorly-drained soils lose N mainly by denitrification, which is very temperature-sensitive. My rule of thumb is that wet conditions in May and June cause denitrification losses, but losses in April are minimal.
Areas with diagonal shading are ‘danger areas’ that are on track to have 12 or more inches of rainfall from May 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 12 or more inches of rainfall since May 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA July 3 July 3 July 3 June 26 June 26 June 26 June 19 June 19 June 19 June 12 June 12 June 12 June 5 June 5 June 5 May 29 May 29 May 29 May 22 May 22 May 22 May 15 May 15 May 15 May 8 May 8 May 8 - Show/Hide
Nitrogen watch 2015
Nitrogen watch for well- and moderately well-drained soils
Well-drained soils are vulnerable mainly to nitrogen loss from leaching. This process can start shortly after fertilizer application (with some delay for ammonia). We have used April 1 to represent a preplant N application date. For ammonia or for applications later than April 1, risk is lower; for applications before April 1, risk is higher.
Areas with diagonal shading are ‘danger areas’ that are on track to have 16 or more inches of rainfall from April 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 16 or more inches of rainfall since April 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA June 30 June 30 June 30 June 28 June 28 June 28 June 21 June 21 June 21 June 14 June 14 June 14 June 7 June 7 June 7 May 31 May 31 May 31 May 24 May 24 May 24 May 17 May 17 May 10 May 10 May 3 May 3 April 26 April 26 April 19 April 19 Nitrogen watch for poorly- and somewhat poorly-drained soils
Poorly-drained soils lose N mainly by denitrification, which is very temperature-sensitive. My rule of thumb is that wet conditions in May and June cause denitrification losses, but losses in April are minimal.
Areas with diagonal shading are ‘danger areas’ that are on track to have 12 or more inches of rainfall from May 1 to June 30. This does not mean that significant loss of N has already happened, just that producers in these areas should be watchful and aware of the potential for N loss and deficiency.
Areas shown in cross-hatch are ‘problem areas’ that have already received 12 or more inches of rainfall since May 1. I expect a majority of fields to have substantial yield loss due to N deficiency when all N was applied pre-plant. I suggest that producers look at their fields and when N stress is seen apply additional N. Rescue N applications are likely to be profitable until tasseling or later in fields with deficiency symptoms. Canopy sensors potentially provide a way to improve distribution of this N application, putting more N where stress is greatest and little or none where corn looks good.
Missouri Midwest Contiguous USA June 30 June 30 June 30 June 28 June 28 June 28 June 21 June 21 June 21 June 14 June 14 June 14 June 7 June 7 June 7 May 31 May 31 May 31 May 24 May 24 May 24 May 17 May 17 May 10 May 10 May 3 May 3