Abstract
To investigate the effects of the application of apple prunings compost on the growth of apple nursery trees and on the chemical properties and aggregate structure of soil, three kinds of composted apple prunings were applied to soil in Wagner pots planted with apple nursery trees. The composts used were piled for one year and two years respectively, plus recycled-use compost, i.e. compost mixed with highly decayed apple prunings compost and piled for one year. For control purposes, plots treated with rice-straw compost and without compost were also prepared. The growth of apple nursery trees on the three plots treated with composted apple prunings was similar to that on the plot treated with rice-straw compost. The chemical properties of the soil were improved by the application of composted apple prunings, especially the recycled-use compost, which increased the exchangeable bases and available nitrogen contents of the soil. While faster formation of soil aggregates by composted apple prunings was not ascertained, organic matter derived from the applied compost clearly tended to accumulate in soil aggregates. These findings show that the application of composted apple prunings promotes the growth of apple nursery trees and is an effective method of improving the chemical properties of soil.
