Application of organic waste composts when producing forest planting material

Most seedlings and saplings of woody plants in the Russian Federation are produced in the open ground in forest nurseries. In order to produce high quality planting material it is necessary to support and preserve soil fertility, which can be obtained by using organic wastes and organic-based fertilizers. Our research is aimed at the assessment of the influence of non-conventional organic fertilizers on fertility of podzols and on the growth rate of seedlings and saplings of woody plants in forest nurseries. Our research shows, that the application of non-conventional organic fertilizers does not re-sult in any accumulation of heavy metal salts in podzols, but optimizes hydro physical and agrochemical properties of the ploughed horizon. The efficiency of non-conventional organic fertilizers depends on their composition, physical and chemical characteristics of the origi-nal components, their doses applied and original fertility of soils. A combined application of non-conventional organic fertilizers and sand results in the optimization of practically all soil fertility parameters in middle clay-loam soils, while application of non-conventional organic fertilizers and clay is optimal for application on light soils. The optimal application dose of non-conventional fertilizers depends on soil texture, woody species and the fertilizer composition. An optimal application dose for Norway spruce on a light clay-loam soil is 50-80 tons/ha, and on a middle clay-loam soil is 149-182 tons/ha. It is 50 tons/ha for Scots pine growing on a sandy loam soil, and 100 tons/ha for the same species growing on a sandy soil or a light clay-loam. For Siberian larch growing on a light clay-loam soil the dose of fertilizer applied should be 150 tons/ha. It is recommended to apply composts con-taining over 50% (by weight) of Category II wastes (substrate) for the amelioration of light soils, and composts containing over 40% (by weight) of Category I wastes (filler) for the amelioration of heavy soils. It would allow for the optimization of soil properties and production of better quality planting material in forest nurseries.