Technical ArticleInfluence of Pecan Biochar on Physical Properties of a Norfolk Loamy SandBusscher, Warren J.1; Novak, Jeff M.1; Evans, Dean E.1; Watts, Don W.1; Niandou, M. A. S.2; Ahmedna, Mohamed2 Author Information 1USDA-ARS, Florence, SC. Dr. Warren J. Busscher is corresponding author. E-mail: [email protected] 2North Carolina A&T State University, Greensboro, NC. Received August 14, 2009, and in revised form November 17, 2009. Accepted for publication November 18, 2009. Soil Science: January 2010 - Volume 175 - Issue 1 - p 10-14 doi: 10.1097/SS.0b013e3181cb7f46 Buy Metrics Abstract Because the southeastern US Coastal Plain has high temperatures and abundant rainfall, its sandy soils have poor physical characteristics and low carbon (C) contents. To increase soil C, we added switchgrass (Panicum virgatum) and nonactivated recalcitrant pecan biochar. Biochar was developed by pyrolyzing ground pecan shells at 700 °C. Biochar had 88% C, 0.4% N (C:N ratio, 220:1); 58% of its C resided in polymerized aromatic ring structures. Biochar treatments were 0, 5, 10, or 20 g kg−1 of soil, which was the Ap horizon of a Norfolk loamy sand, a thermic Typic Kandiudult. Switchgrass was ground to a fine powder and added to the biochar treatments at rates of 0 or 10 g kg−1. Treatments were incubated in 750-g columns for 70 days at 10% (wt wt−1) water content. Biochar decreased soil penetration resistance; adding switchgrass also decreased it by the end of the experiment. Biochar and switchgrass affected aggregation, infiltration, and water-holding capacity; but results were mixed. Although the nonactivated biochar (and switchgrass) improved some soil physical characteristics, other biochar formulations may have more of an effect on soil properties. © 2010 Lippincott Williams & Wilkins, Inc.