Evaluation Of Biomass Power Plant Wood Ash As a Liming Material For Agricultural Soils In East Texas.

Application of wood ash from biomass power plants has the potential to reduce soil acidity, improve nutrient availability and increase yields of agricultural crops. A greenhouse pot study was conducted to compare effects of wood ash and commercial agricultural limestone on soil properties and growth of common bermudagrass. The experiment was a randomized complete block design with three lime sources applied at six rates on two acid soils grouped into four blocks. Lime sources were mixed with one thousand grams of each acid soil at six rates corresponding to 0, 0.5, 1, 1.5, 2, and 4 times the lime requirement of each soil expressed on an effective calcium carbonate equivalent (ECCE) for each of the three lime sources. Core soil samples were collected from each pot after three weeks of incubation and final clipping (seventeen weeks). Samples were analyzed for salt pH, buffer pH, electrical conductivity, Mehlich III extractable P, K, Ca, Mg, and KCl extractable Al and Mn. Grass sprigs were planted in pots after incubation. Grass was clipped on day 42 and 82 from planting. Lime application significantly increased soil pH of both soils at the end of incubation. Change in soil pH was not significantly different for lime sources except at highest rates where wood ash amended soils were higher. Grass yield increased by as much as 100 percent in amended Darco soils at half the recommended lime rate, however differences were not observed beyond this rate. Grass did not respond to liming effect or lime sources in Nacogdoches soil. Results indicate that wood ash is as effective in changing soil pH as commercially available limestone sources.