RT Journal Article SR Electronic T1 Laboratory Assays on the Effects of Aerated Compost Tea and Fertilization on Biochemical Properties and Denitrification in A Silt Loam and Bt Clay Loam Soils JF Arboriculture & Urban Forestry (AUF) FD International Society of Arboriculture SP 269 OP 277 DO 10.48044/jauf.2011.035 VO 37 IS 6 A1 Scharenbroch, Bryant C. A1 Treasurer, William A1 Catania, Michelle A1 Brand, Vincent YR 2011 UL http://auf.isa-arbor.com/content/37/6/269.abstract AB Aerated compost tea (ACT) is gaining interest as a nutrient amendment for urban trees. This study examined the effects of ACT, synthetic fertilizer, and deionized water on 15 biochemical properties with two soil types. Significant effects for pH, Mg2+, Na+, C, N, and C/N ratio were not observed among treatments. No differences between dilute ACT (ACTd) at 22.4 kL ha−1 and water were detected. Soil K+ was greater with ACT concentrate (ACTc) at 224 kL ha−1 compared to 30-10-7 fertilizer at 195 kg N ha−1 with A horizon soils. Soil K+, NH4+, and microbial respiration were greater with ACTc compared to water in A soils. Soil P (A soils only), NO3− (Bt soils only), dissolved organic N, microbial biomass N, and N mineralization were greater with fertilizer compared to ACT. Increases in denitrification were seen with ACTc compared to fertilizer and water in the first 24 hours (+4 to +12 mg N2O kg−1), but greater increases were observed with fertilizer at hours 48 and 96 (+65 to +127 mg N2O kg−1). Greatest improvements in soil fertility were observed with fertilization. Minor improvements in soil fertility were observed with ACTc, and denitrification losses were lower with ACTc compared to the fertilizer.