Technical Abstract: We tested 12 different organic sources as amendments for E horizon or a mixture of E and Bt horizons of a southeastern coastal loamy sand. Amendments included biochar, cellulose, corn stalk, corn starch, cotton hull, cotton meal, manure residual, peanut hull, poultry litter, soybean plant, wheat straw, and wood shavings. We hypothesized that amendments would increase carbon and improve soil physical/chemical properties. Amendments of ~1% organic carbon content were allowed to incubate for 60 days. Over the course of the experiment, cellulose, corn stalk, and corn starch gave the greatest improvement in aggregation; the control, peanut hull, poultry litter, wood shavings, and biochar gave the lowest. Cotton meal and poultry litter had the highest carbon dioxide evolution; biochar had the lowest. Corn starch and poultry litter had the highest amount of dissolved organic carbon leached; the control and biochar had the lowest. Biochar, wood shavings, and corn starch had the highest soil penetration resistance; cellulose and cotton meal had the lowest. Poultry litter and manure residual had the greatest improvement in water holding capacities; cellulose, biochar, and soybean plant had the lowest, though all were better than the control. The Bt horizon mixed into the E essentially added clay, which improved parameters for most treatments. All treatments improved the soil in one way or another – more carbon, softer soil, or more aggregation. Biochar retained the most carbon throughout the incubation period.