Disposal of Composted Municipal Waste in a Plantation of Young Slash Pine: Effects on Soil and Trees

Abstract

AbstractA field experiment was conducted to determine the effects of disposal of garbage compost on soil and trees in a 2‐year‐old plantation of slash pine (Pinus elliottii Engelm. var. elliottii) on an excessively drained sandy soil in central Florida. The highly carbonaceous compost was applied at three rates (0, 4.4, and 44 metric tons/ha) in factorial combination with inorganic N fertilizer (0 vs. 224 kg/ha) and with disking vs. no disking following compost application.At 44 metric tons/ha the compost increased the amount and extended the period of moisture availability to the trees during a drought occurring soon after treatment. Disking (with or without applied compost) also improved soil moisture availability temporarily by reducing weed competition. The compost, particularly at the high rate, decreased soil acidity, and modestly increased soil organic matter, cation exchange capacity, and exchangeable Ca, Mg, and K.Nitrogen concentration in pine foliage was reduced following application and incorporation of the high rate of compost, but recovery to pretreatment levels was rapid. Concentration of K in foliage was increased by compost application; this effect was persistent.Height growth of the trees was significantly increased only by disking; this effect diminished in the second year following treatment. No adverse effects of compost on soil or trees were observed, but aesthetics of the site were degraded somewhat by the residue of nondegradable particulates which persisted on the soil surface.