Author(s):
Sailesh Sigdel, Heather Karsten
Abstract:
Nitrogen (N) management is critical in corn (Zea mays L.) production due to its significant impact on yields, economic costs, water and air quality, and greenhouse gas emissions. Growers' practices aimed at ensuring maximum yields often lead to the application of more N than the crop can utilize. Applying manure before corn planting and then side-dressing N fertilizer later can enhance N use efficiency and reduce environmental losses. Despite these advantages, predicting the economically optimal N rate (EONR) remains challenging, often resulting in excessive side-dress N applications that increase both costs and environmental risks. Despite advancements in N recommendations, which range from sensor-based technologies like SPAD and NDVI to models that incorporate real-time weather information along with local soil and crop management factors, there remains a need to refine side-dress N recommendations due to the inherent uncertainty in estimating mineralizable N in fields with varied crop and manure management histories. While several N management tools show promise, their accuracy and reliability in side-dress applications have not been extensively evaluated in the U.S. mid-Atlantic region. \n The objective of this research was to identify side-dress nitrogen (N) recommendation methods that provide accurate N recommendations across diverse crop and manure management histories. The study was conducted at Rock Springs, PA, and on-farm locations across Pennsylvania using no-till corn production systems representing 21 different prior-crop and manure management histories, including injected and surface-broadcast manure applications without incorporation. Side-dress N recommendation tools including SPAD, Adapt-N, the Cover Crop and Soil Organic Matter (CC & SOM) N Credit Tool, NDVI, the Penn State Agronomy Guide, and the Pre-Side-dress Nitrate Test (PSNT) were evaluated at the same corn development stage from 2021 to 2023. Following tool recommendations, multiple side-dress N fertilizer rates were applied to establish N response curves and determine the economically optimal nitrogen rate (EONR) for each environment.
Funder:
USDA NIFA
Award Title:
Consortium for Cultivating Human And Naturally reGenerative Enterprises: Grass2Gas
Award Number:
2020-68012-31824
Keywords:
Adapt-N, Economically Optimal Nitrogen Rate (EONR), Normalized Difference Vegetation Index (NDVI), Pre-Sidedress Nitrate Test (PSNT), Soil Plant Analysis Development (SPAD), corn, dairy manure, nitrogen management, nitrogen recommendation tools, no-till agriculture, side-dress nitrogen
Project (Abbreviated name):
G2G_Karsten_early_season_N
Team:
Grass2Gas
Geographic Location:
The state of Pennsylvania, US.
Families:
Bovidae, Fabaceae, Poaceae
Species:
Bos taurus, Dactylis glomerata, Lolium multiflorum, Medicago sativa, Secale cereale, Trifolium pratense, Zea mays
Data Mirror:
Data Table Column Names and Descriptions
| Table name | Column name | Data type | Units | Column description |
|---|---|---|---|---|
| Adapt N tool | Adapt N tool pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| Adapt N tool | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| Adapt N tool | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| Adapt N tool | method of manure application | string | NA | The method used to apply manure. |
| Adapt N tool | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| Adapt N tool | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| Adapt N tool | tool | string | NA | Sidedress nitrogen fertilizer recommendations were generated using the Adapt-N nitrogen decision support system for corn grown in no-till dairy cropping systems from 2021 through 2023. |
| Adapt N tool | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| Agronomy Guide | Agronomy Guide pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| Agronomy Guide | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| Agronomy Guide | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| Agronomy Guide | method of manure application | string | NA | The method used to apply manure. |
| Agronomy Guide | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| Agronomy Guide | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| Agronomy Guide | tool | string | NA | Sidedress nitrogen fertilizer recommendations were generated using the Penn State Agronomy Guide for corn grown in no-till dairy cropping systems from 2021 through 2023. |
| Agronomy Guide | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| Normalized Difference Vegetation Index | Normalized Difference Vegetation Index pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| Normalized Difference Vegetation Index | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| Normalized Difference Vegetation Index | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| Normalized Difference Vegetation Index | method of manure application | string | NA | The method used to apply manure. |
| Normalized Difference Vegetation Index | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| Normalized Difference Vegetation Index | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| Normalized Difference Vegetation Index | tool | string | NA | Recommended sidedress nitrogen rates were generated from NDVI-based assessments of crop nitrogen status using canopy reflectance measurements and GreenSeeker (Trimble Inc., Sunnyvale, CA, USA) associated recommendation algorithms. |
| Normalized Difference Vegetation Index | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| Pennsylvania State Nitrogen Test | Pennsylvania State Nitrogen Test pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| Pennsylvania State Nitrogen Test | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| Pennsylvania State Nitrogen Test | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| Pennsylvania State Nitrogen Test | method of manure application | string | NA | The method used to apply manure. |
| Pennsylvania State Nitrogen Test | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| Pennsylvania State Nitrogen Test | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| Pennsylvania State Nitrogen Test | tool | string | NA | Recommended sidedress nitrogen rates were generated according to Pennsylvania State Extension PSNT interpretation guidelines. |
| Pennsylvania State Nitrogen Test | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| SPAD chlorophyll | SPAD chlorophyll pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| SPAD chlorophyll | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| SPAD chlorophyll | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| SPAD chlorophyll | method of manure application | string | NA | The method used to apply manure. |
| SPAD chlorophyll | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| SPAD chlorophyll | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| SPAD chlorophyll | tool | string | NA | Recommended sidedress nitrogen rates were generated using SPAD chlorophyll meter assessments of corn nitrogen status and associated recommendation algorithms. |
| SPAD chlorophyll | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| corn grain N response | block | float | number | The statistical block that plots had treatments randomized within. |
| corn grain N response | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| corn grain N response | corn grain N response pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| corn grain N response | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| corn grain N response | plot id | string | NA | A unique identifier for the plot this data was collected in. |
| corn grain N response | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| corn grain N response | sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| corn grain N response | treatment | string | NA | The method used to apply manure. |
| corn grain N response | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| corn grain N response | yield bu a 15 5 percent mc | float | bushelPerAcre | Corn grain yield in bushels per acre normalized to 15.5% moisture content. |
| corn silage N response | block | float | number | The statistical block that plots had treatments randomized within. |
| corn silage N response | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| corn silage N response | corn silage N response pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| corn silage N response | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| corn silage N response | dry yield t a | float | tonPerAcre | Corn silage yield after normalizing for 0% moisture. |
| corn silage N response | plot id | string | NA | A unique identifier for the plot this data was collected in. |
| corn silage N response | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| corn silage N response | sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| corn silage N response | treatment | string | NA | The method used to apply manure. |
| corn silage N response | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| corn silage N response | yield t a 65 percent moisture | float | tonPerAcre | Corn silage yield normalized for 65% moisture. |
| cover crop N tool | corn environment | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| cover crop N tool | cover crop N tool pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| cover crop N tool | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| cover crop N tool | method of manure application | string | NA | The method used to apply manure. |
| cover crop N tool | recommended sidedress nitrogen rate kg n ha | float | kilogramPerHectare | Recommended sidedress nitrogen rate (kg N/ha). |
| cover crop N tool | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| cover crop N tool | tool | string | NA | Recommended sidedress nitrogen rates were calculated by estimating nitrogen credits from cover crop biomass and soil organic matter and subtracting those credits from crop nitrogen requirements. |
| cover crop N tool | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| site details | corn environment site | string | NA | Environment or site name. Information about sites can be found in table site_details. |
| site details | crop entry | string | NA | The crop entries included in the study were corn silage following a winter cereal rye cover crop in an organic grain rotation (R, Cs, O), corn silage following a winter cereal rye cover crop in a grain rotation with rye (R, Cs, R), corn silage following annual ryegrass and red clover cover crops interseeded into corn grain the previous year (Int, Cs), and corn grain following a winter cereal rye cover crop (R, Cg). Perennial forage entries were excluded because cover crop nitrogen credits were not applicable. Full abbreviations used were: A+Og = Alfalfa + Orchardgrass; Cs = Corn silage; Cg = Corn grain; Int = Interseeded annual ryegrass + clover mix; O = Oats; R = Rye cover crop; Rs = Rye silage; S = Soybean; SS = Sorghum-sudangrass. Production year notation: 1 = First full production year; 2 = Second full production year; 3 = Third full production year (for multi-year perennial crops such as alfalfa + orchardgrass). |
| site details | manure application method | string | NA | The method used to apply manure. |
| site details | manure since last harvest | string | NA | Has manure been applied since the last harvest. |
| site details | measured EONR kg N per ha | integer | kilogramPerHectare | The measured economic optimum N rate (EONR) applied at side dressing for sites was determined from experimental side dress N response curves. |
| site details | previous crop | string | NA | The crop in this environment the previous year. |
| site details | previous crop management | string | NA | Relevent details on how the previous crop in this environment was managed. |
| site details | rotation | string | NA | The cropping system rotation in the larger Penn State LTAR Sustainable Dairy Cropping Systems experiment. |
| site details | side dress n responsiveness | string | NA | P-value of a mixed-model ANOVA that tested for a difference in N responsiveness between sites with block as a random effect. |
| site details | site details pkey | integer | dimensionless | A unique primary key identifier for each row in this table. |
| site details | year | dateTime | NA | The calendar year for this entry. This dataset contains data from 2021-2023. |
| site details | yield plateau Mg per ha dry weight | float | megagramPerHectare | The quadratic plateau function fit with PROC NLIN. The point on a response curve was used to determine the economically optimum N rate (EONR), which is considered a threshold rate or range that maximizes return on investment in N fertilizer. 4A, 4B, 5A, and 5B in 2022 did not meet the expected yield goal for the environment. |