1. Edwin M. Lentz, Agriculture and Natural Resources Educator, OSU Extension-Hancock County, 7868 CR 140, Findlay OH 45840
Abstract Methods Test weight, head number, and flag leaf N
ESN is a relatively new controlled-release N product for Ohio • Medium maturity variety – Hopewell concentration means in response to 80 lb N/acre
wheat production. It is a polymer coated urea that the nitrogen • Nitrogen applied prior to planting – 25 lb/acre
release is dependent upon temperature and moisture. The • Plot dimension – 10 x 70 ft
from various N sources
objective of this study was to evaluate ESN as a nitrogen source • Seeded at 1.6 million seeds per acre into soybean stubble - Test Weight Heads Flag leaf
N Source
for wheat production in northwest Ohio. In Fall 2009, medium- no-till, seeded within 7 days of fly-free date lb/bu /ft row N%
maturity variety ‘Hopewell’ was established into soybean stubble • Leaf analysis at heading - 50 flag leaves collected per plot
on the OARDC Northwest Research Station near Custar, Ohio. • Five treatments broadcast applied at early green-up, 80 lb Urea 58.9c 52.0 3.8
Treatments included Urea, ESN, 75:25 urea:ESN blend, 50:50 N/acre
urea:ESN blend, and a 25:75 urea:ESN blend. A nitrogen rate of o Urea 46-0-0 75 Urea: 25 ESN 58.8c 52.0 3.7
80 pounds per acre was applied at greenup for each treatment. o ESN 44-0-0
Experimental design was a completely randomized block o 75:25 Blend – 75% Urea, 25% ESN
replicated four times. Analysis was a simple ANOVA. Grain yield, o 50:50 Blend – 50% Urea, 50% ESN 50 Urea: 50 ESN 59.5ab 52.0 3.8
test weight, spike number, and N uptake were measured for each o 25:75 Blend – 25% Urea, 75% ESN
treatment. Significant differences were observed among • Experimental design - randomized block replicated four times 25 Urea: 75 ESN 59.2bc 44.0 3.7
treatments for yield. ESN yields were significantly less than urea • Statistical analysis – simple ANOVA
and the 75:25 and 50:50 urea:ESN blends. The 75:25 urea:ESN
and 50:50 urea:ESN blends were similar to urea. Yields of the Results ESN 59.9a 44.0 3.5
25:75 urea:ESN blend was similar to ESN. ESN alone would not be
an adequate N source for wheat production in northwest Ohio. Grain yield for ESN, Urea and lsd0.05 0.5 ns ns
It may be a viable product when blended with urea as long as the
blend contains more than 50% urea. 78 Urea-ESN blend Treatments
cv 0.5 11.1 5.1
Introduction 76 77.1 means with different letters are significantly different
Environmentally Smart Nitrogen (ESN®) is a relatively new ns - no significance difference among means (p<0.05)
74 75.4
technology fertilizer for the wheat industry in Ohio. It is a lsd0.05 = 3.9
bushels per acre
polymer-coated urea product developed to perform as a 74.0
controlled-release nitrogen fertilizer. Limited University research 72
has been completed in Ohio that compares ESN to urea. Since Conclusions
ESN is more expensive to manufacture than urea, industry would 70
• Lower yields may occur when ESN is applied as the only spring
like to blend ESN with urea to lower the cost per acre; 70.0
N source compared to urea
information is lacking on the potential benefits or problems with 68
68.3 • Yields may be similar between urea-ESN blends and urea
urea:ESN blends.
66 provided that urea contributes 50% or more of the total N
requirements
Objective 64 • Limited N released early in the spring growing season may have
Evaluate ESN as a nitrogen source for Ohio 62
lowered yields from ESN alone as suggested by the decrease in
number of heads compared to urea
wheat production Urea 75 Urea: 50 Urea: 25 Urea: ESN
25 ESN 50 ESN 75 ESN • ESN may provide more N later in the growing season than urea
as suggested by the increase in test weights
N Source
Result Highlights Outreach and Impact
• ESN alone yielded less than urea
• Data has been presented at 10 county and regional meetings to
• Urea-ESN blends were similar to urea when blends
approximately 700 producers, consultants, and retailers
contained ≤50% ESN
• Test weights were larger for ESN alone than urea • As a result of this and other research, industry now blends ESN
• Heads for ESN < urea at p< 0.10, but similar at p<0.05 with urea or ammonium sulfate to minimize risk of yield loss
• Leaf nitrogen concentration was similar among all N that may occur from some environments in Ohio
ESN Urea sources at heading
Acknowledgement
ESN and urea:ESN blends were provided by Crop Production Services, Attica, OH