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To increase wheat (Triticum aestivum L.) yield in Kentucky, many producers are increasing nitrogen (N) rates to 160 or 180 lb N/ acre and applying a plant growth regulator (PGR) to reduce plant height and lodging. Replicated field trials were established in three environments (Princeton 2014, Princeton 2015, Lexington 2015 to determine whether increased nitrogen rates and/or PGR applications increase yield or alter the structure of the wheat plant. Five N rates (0, 50, 100, 150, 200 lb N/acre), three cultivars (Pioneer Brand 25R32, Pembroke 2014, Truman), and two PGR treatments (nontreated control, Palisade EC [12.5 oz/acre]) were evaluated. The PGR treatment consistently increased the number of spikelets head -1 ; however, grain yield was not increased. Plant height was reduced in two environments (Princeton 2014, Lexington 2015) following the PGR treatment. Height reductions were more pronounced in environments with unusually cold winter and early-spring temperatures in which untreated wheat was already significantly shorter than years with less severe winter and spring temperatures. Stem diameter increases were observed when wheat height was not shortened. Grain yield of Pembroke 2014 increased as N rates increased; maximum grain yield for the other two cultivars was achieved at 100 lb N/acre. These results indicate that the PGR did not consistently reduce plant height or increase grain yield.

a b s t r a c tComposting swine slurries has several advantages, liquid slurries are converted to solids at lower moisture, the total volume and weight of material is reduced and the stabilized product is more easily transported off-site. Despite this, swine waste is generally stored, treated and applied in its liquid form. High-rise finishing facilities (HRFF) permit liquid slurries to be converted to solids which are partially decomposed underneath the HRFF and then finished in compost windrows. The purpose of this study was to evaluate the effect of turning frequency and ambient weather conditions on biological, physical and chemical properties of composted slurry-woodchip mixtures from HRFF. Compost trials were conducted in either fall (FT) or spring (ST) and piles were turned once or three times per week or upon compost temperature reaching 65°C. Physical, chemical and microbiological characteristics were measured over the course of 112 (FT) or 143 (ST) days of composting. Total carbon, total nitrogen (N) and inorganic N decreased in all piles. Ammonium decreased while nitrate increased in all piles (including unturned), but total N losses were greatest in piles turned more frequently during the ST. Microbial populations of nitrifiers were dominated by ammonia-oxidizing archaea (3.0 Â 10 3 -4.2 Â 10 6 cells g À1 compost) but ammonia oxidizing bacteria (below detection to 6.0 Â 10 5 cells g À1 compost) varied in response to turning and compost temperature; denitrifiers were present in high concentrations throughout the process. Swine HRFF materials composted well in windrows regardless of turning frequency and despite significant differences in starting materials and low initial C/N. Volume reduction, low moisture and low readily degradable organic matter suggest that the finished compost would have lower transportation costs and should provide value as a soil conditioner. Published by Elsevier Ltd.

Currently accepted pedotransfer functions show negligible effect of managementinduced changes to soil organic carbon (SOC) on plant available water holding capacity (θ AWHC ), while some studies show the ability to substantially increase θ AWHC through management. The Soil Health Institute's North America Project to Evaluate Soil Health Measurements measured water content at field capacity using intact soil cores across 124 long-term research sites that contained increases in SOC as a result of management treatments such as reduced tillage and cover cropping. Pedotransfer functions were created for volumetric water content at field capacity (θ FC ) and permanent wilting point (θ PWP ). New pedotransfer functions had predictions of θ AWHC that were similarly accurate compared with Saxton and Rawls when tested on samples from the National Soil Characterization database. Further, the new pedotransfer functions showed substantial effects of soil calcareousness and SOC on θ AWHC . For an increase in SOC of 10 g kg -1 (1%) in noncalcareous soils, an average increase in θ AWHC of 3.0 mm 100 mm -1 soil (0.03 m 3 m -3 ) on average across all soil texture classes was found. This SOC related increase in θ AWHC is about double previous estimates. Calcareous soils had an increase in θ AWHC of 1.2 mm 100 mm -1 soil associated with a 10 g kg -1 increase in SOC, across all soil texture classes. New equations can aid in quantifying benefits of soil management practices that increase SOC and can be used to model the effect of changes in management on drought resilience.

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