Soil Nutrient Accumulation in an Orchardgrass

1
Soil Nutrient Accumulation in an Orchardgrass
Hayfield following Poultry Litter
Application R.A. Gilfillen1, B.B. Sleugh2, W.T.
Willian1, and M.L. Futrell1 Western Kentucky
University1 and Dow AgroSciences, Des Moines, IA2

• Materials and Methods
• General Site Information
• WKU Agricultural Research and Education Complex,
  Bowling Green, KY
• Fifteen random soil cores were taken from each
  plot at the end of the 4 year study to a depth of
  15 cm.
• Soil type Pembroke silt loam (Mollic Paleudalf)
• Soil slope 0-2
• Fertilizer application split application -
  March 26 and Aug. 30, 2001, March 21 and Aug. 16,
  2002, March 24 and Aug. 22, 2003 and April 2
  and August 10, 2004.
• Poultry litter applications (wet weight basis)
• 2001 2002 2003 2004
• ---------------------------Mg ha-1
  PL----------------------------
• NPL 21.0 20.3 16.0 16.0
• PPL 3.0 2.7 3.5 2.9
• NPPL 3.0 2.4 4.2 2.2
• I ----- ------ ------ ------
• Inorganic applications

Abstract Poultry litter can be an
excellent source of nutrients for forage
production. If properly managed, litter can be
returned to land however, one concern regarding
land application of poultry litter is soil
nutrient accumulation. Applying poultry litter
to land at recommended crop N rates can lead to
an accumulation of P, K, and some micronutrients
in the soil. This study was developed to observe
accumulation in nutrient content of the soils
after four years of fertilization with poultry
litter and/or inorganic fertilizers. A
completely randomized block design consisting of
four treatments was utilized an inorganic N, P,
K fertilizer (I), poultry litter applied
according to recommended P rate (PPL), poultry
litter applied according to recommended N rate
(NPL), and poultry litter applied at recommended
P rate with supplemental inorganic N fertilizer
(NPPL). Soil samples from the last year of the
study were analyzed for pH, CEC, organic matter,
and available nutrient content. Differences
between treatments were found for CEC along with
available P, S, Cu, Zn, and Na. In each of these
measurements, the NPL treatment was significantly
higher than all other (plt0.01). Indications are
that while the increased CEC would be useful, the
increase in availability of P, Cu, Zn, and Na can
lead to more serious environmental concerns.
Cu
Zn
plt0.05
plt0.01

OM
CEC

• Introduction
• Poultry Production in Kentucky
• In 1991, there were 2.2 million broilers
  produced. In 2000 there were 20.8 million
  produced. (KASS, 2001)
• Poultry production moved to the 2nd highest
  agricultural cash industry in 2001 (KASS, 2001).
• Most of the poultry production is found in
  four counties in the western part of the state,
• which leaves limited land area for poultry
  waste application due to transportation costs.
• Nutrient accumulation from poultry litter
  application
• Soil nutrient imbalances can result from long
  term application of incorrect litter rates
  (Sistani et al., 2004)
• Poultry litter is high in P and some
  micronutrients in relationship to the quantities
  required by plants (Sistani et al., 2004).
• There is greater concerns over P accumulations
  when poultry litter is applied based on N content
  
• (Sharpley et al., 2003Franzluebbers et al.,
  2002).
• Soil P accumulations from poultry litter
  application
• Broiler litter applied to meet N requirements can
  give 8x as much P as needed (Franzluebbers et
  al., 2002)
• Extractable P was six times greater in litter vs.
  non-littered soils to a depth of 60 cm (Kingery
  et al., 1994).
• Micronutrient accumulation from poultry litter
  application

plt0.05

• Summary
• After four years of litter application, available
  P, K, Cu, and Zn were all observed to be highest
  in the NPL treatment in comparison to all others.
  This would again indicate that these nutrients
  are accumulating faster in the N rate (NPL)
  treatment than in the treatments involving P rate
  of application (NPPL or PPL) or inorganic
  fertilizer (I).
• Organic matter content was highest in the NPL and
  I treatments. The NPL treatment was higher than
  either the NPPL or PL treatments. Cation
  Exchange Capacity was greater in the NPL
  treatment than all others.
• While organic matter and CEC increases are
  beneficial to orchardgrass production in
  Kentucky, the potential environmental concerns
  that excess nutrients create is of greater
  significance.

• Results and Discussion
• Available Nutrient Accumulations (Figures 1 and
  2)
• In the NPL treatment, P, K, Cu, and Zn were all
  in higher concentrations than in the remaining
  treatments (plt0.05 0.01)
• Organic matter content (Figure 3)
• Addition of poultry litter and additional
  vegetative growth led to higher organic matter
  contents in the NPL and I treatments in
  comparison to the other treatments (plt0.05).
• The I, NPPL, and PPL treatments were all similar
  in organic matter content (plt0.05)
• Cation exchange capacity (Figure 3)
• Additions of poultry litter to meet N
  requirements led to higher CEC than all other
  treatments (plt0.05).

• References
• Franzluebbers, A.J., J.A. Stuedemann, and S.R.
  Wilkinson. 2002. Bermudagrass management in the
  southern piedmont USA. II. Soil phosphorus.
  Soil Sci. Soc. Am. J. 66291-298.
• Kentucky Agricultural Statistics Service. 2001.
  Kentucky Agricultural Statistics. Frankfort, KY.
  
• Kingery, W.L., C.W. Wood, D.P. Delaney, J.C.
  Williams, and G.L. Mullins. 1994. Impact of
  long-term application of broiler litter on
  environmentally related soil properties. J.
  Environ. Qual. 23 139-147.
• Sharpley, A.N. 2003. Soil mixing to decrease
  surface stratification of phosphorus in manured
  soils. J. Environ. Qual. 321375-1384.
• Sistani, K.R., G.E. Brink, A. Adeli, H. Tewolde,
  and D.E. Rowe. 2004. Year-round soil nutrient
  dynamics from broiler litter application to
  three bermudagrass cultivars. Agron. J. 96
  525-530.

• Objectives
• After four years of application do soil
  nutrients accumulate faster and at higher amounts
  based on the four fertility treatments.
• Determine which nutrients are accumulating in
  the soil that might be of environmental concern.

Acknowledgements The authors wish to
thank the USDA-ARS at Bowling Green and
Mississippi State for providing funding and
cooperation. Many thanks to the WKU Agronomy
graduate and undergraduate students for
assistance with field sampling and laboratory
analysis.