These field experiments were conducted in connection with the recent upsurge of interest in composting as a disposal method for municipal refuse. Heavy applications of compost made from municipal refuse and sewage sludge were evaluated for production of forage sorghum (Sorghum bicolor L. Moench × Sorghum sudanense P. Stapf.) and common bermudagrass (Cynodon dactylon L.) at Muscle Shoals, Ala., and for corn (Zea mays L.) at Johnson City, Tenn.Positive yield responses were observed t o annual compost application at rates up to 80 metric tons/ha on bermudagrass, 143 metric tons/ha on sorghum, and 112 metric tons/ha on corn. However, the highest yields of bermudagrass or sorghum attained from compost application were equaled or surpassed by application of fertilizer nitrogen (N) at the rate of 180 kg/ha together with adequate phosphorus (P) and potassium (K). Compost‐induced K deficiency was not observed in any crop.Incorporation of compost over a 2‐year period significantly increased moisture‐holding capacity and decreased bulk density and compression strength of the soil. The pH, organic matter, K, calcium (Ca), magnesium (Mg), and zinc (Zn) levels were also increased. Soil and plant tissue analyses indicated that potentially toxic amounts of Zn could accumulate in the soil if compost were applied at rates totaling several hundred tons/ha over a few years.

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