Thesis
Thesis Document 07172017 revised.pdf
(2017)
Abstract
iv
Abstract
The increasing cost of commercial fertilizers and the avail
ability of animal waste
that has high nutrient content have led to producers utilizing animal waste such as poultry
litter in their fertility programs. This increased use has raised concerns as to what are the
optimum rates to apply to meet crop needs and
how will long term use at high rates of
litter effect soil test levels of nutrients such as phosphorus and potassium. The objective
of this study was to address these concerns. This study has been ongoing since 1998 with
treatments of zero to seven tons
of litter being applied in years where corn was planted
and then in years where soybeans were planted the residual fertility from the previous
years of applications were observed. In 2005, 2006, and 2009; 23
0 lbs
/A of commercial
phosphorus (P
2
O
5
) and 250
lbs
/A of commercial potassium (K
2
O) were applied to the
plots treated with the historical rates of one and two tons per acre of broiler litter. This
study looked at the effects residual fertility from past broiler litter applications had on soil
nutrient
levels and plant nutrient uptake during the 2013 soybean growing season, as well
as, the effect on soybean yield in 2012 and 2013. In 2014 the study was returned to corn
and the one through seven tons per acre broiler litter treatments were again applied
. Data
reported from 2014 included soil test results, R1 corn ear leaf tissue analysis, and yield.
In 2007 a positive correlation between soybean uptake of copper and yield was
observed (Upchurch, 2008). In 2009 a second study to compliment the broiler
litter study
was started where the effects of pre plant soil
applied rates 0, 10, and 20 lbs
/A copper on
soil test copper levels, plant uptake of copper, and yield
were evaluated
(Scott, 2010).
This study was continued with only yield data being reported
for the 2012 growing
season and soil test results, plant tissue analysis, and yield data being reported for the
soybeans in 2013 and the corn in 2014.
Mean soil test values for pH, organic matter, and total nitrogen, though not always
significant, tended
to be higher in plots treated with the higher rates of broiler litter. Plots
treated with the higher rates of broiler litter and those treated with the past rates of one
and two tons per acre rates of broiler litter, which also received high rates of comm
ercial
phosphorus (P
2
O
5
) and potassium (K
2
O) fertilizers three years of the study, tended to
have higher soil test phosphorus and potassium values. No statistical difference in mean
soil test calcium values were observed among the one through seven tons p
er acre rates of
broiler litter treatments in either year. Mean soil test magnesium values were highest in
plots treated with the four through seven tons per acre rates of broiler litter. In both 2013
and 2014 mean soil test values for zinc and copper we
re highest in the plots treated with
the seven tons per acre rate of broiler litter, then soil test values declined steadily as the
rate of litter applied was reduced. Mean soil test values for boron were only collected in
2013, but followed a similar pat
tern as zinc and copper. Mean values for manganese did
not seem to follow a pattern based on fertility, as in both years the highest values came
from the no litter treatment, but were not significantly different from other treatments of
moderate to high r
ates of broiler litter. Though not always significantly different, in both
years, mean soil test values for iron tended to be lowest in the no litter and three tons per
acre rates of broiler litter treatments.
No statistical differences from R5 soybean l
eaf tissue analysis or R1 corn ear leaf
analysis were observed for plant uptake of nitrogen, magnesium, calcium, sulfur, zinc,
manganese, or iron. Tissue analysis from both years showed that plant uptake of
phosphorus was significantly lower in the plots
treated with no litter, than in plots
v
receiving any rate of litter. No statistical difference in plant uptake of potassium was
observed from soybean tissue samples in 2013, but R1 corn ear leaf analysis in 2014
revealed that plant uptake of potassium was
statistically lower in plots that received no
litter, compared to plots that received any rate of broiler litter. Boron and copper uptake
were statistically lower in soybeans treated with the seven tons per acre rate of broiler
litter than the zero throug
h five tons per acre treatments in 2013, but no statistical
difference in boron or copper uptake by corn was observed in 2014.
No statistical difference in soybean yield was observed among broiler litter
treatments in 2012 due to extended dry periods dur
ing the growing season. In 2013 the
soybeans treated with past applications of seven tons per acre of broiler litter had
statistically higher yields than all other treatments except the one ton per acre treatment,
which was not significantly different. I
n 2014, corn that received the five through seven
tons per acre rates of broiler litter tended to have higher yields, due in part to the amount
of nitrogen supplied by the litter.
In both 2013 and 2014 mean soil test values for copper were significantly h
igher
in the plots receiving
the 2009 application of 20 lbs
/A of copper and the soil test values
declined steadily as the rate applied was reduced. Despite the significant differences in
soil test copper values, no statistical differences in plant uptake
of copper were observed
form R5 leaf tissue analysis in 2013 or R1 corn ear leaf analysis in 2014. Although no
statistical differences in yield were observed among the treatments from 2012 to 2014, a
strong trend was observed where th
e plots treated with
the 10 lbs
/A application of copper
in 2009, yielded highest among treatments.
Keywords
- broiler litter,
- copper,
- corn,
- soybeans
Disciplines
Publication Date
Summer August 4, 2017
Degree
MS
Field of study
Agriculture
Department
Agricultural Sciences
Advisor
Dr. David Ferguson
Citation Information
Jesse Gray. "Thesis Document 07172017 revised.pdf" (2017) Available at: http://works.bepress.com/jesse-gray/1/