Review of second rotation silviculture of Pinus radiata plantations in southern Australia: establishment practice and expectations

Summary

The retention of litter and logging residue as a source of nutrients and organic matter for the next crop, as well as a mulch to conserve soil moisture, are recognised as primary factors influencing the productivity of successive crops of radiata pine planted on sandy soils, and are also likely to be relevant, though perhaps to a lesser extent, on more fertile soils. The influence of site and stand characteristics on the implementation of these principles is discussed with special reference to radiata pine on infertile sands.

On infertile sands, improved early growth in the second rotation has been achieved from a variety of practices. In each case, the improvement appears to be largely as a result of increases in both the availability of water (weed control and/or mulching) and nitrogen (inputs from either fertiliser, fixation by legumes, or from accelerated mineralisation of organic N in logging residue). The significance of these early results in terms of productivity over the full rotation is discussed in relation to soil water availability and studies of the influence of water and nitrogen treatments on the water-use efficiency of radiata pine seedlings.