Effects of Planting Scale and Management Level on Macadamia Nut Yield

Planting area, nut yield, plantation management were analyzed of main producing countries, China and Yunnan Province by using the methods of reference review, field investigation, face-to-face communication, and conference discussion. The effects of planting scale and management level on the nut yield of Macadamia were evaluated. The results showed Yunnan had become the largest planting area of Macadamia in the world, which the planting area had accounted to about 90% of China and 54.3% of the world, but the nut production(in-shell) was only 17.4% of the world. Soil fertilizer management, shaping and pruning technology and pest occurrence of plantation were the key limiting factors for efficient production with high quality for Macadamia. The average annual fertilization frequency of individual farmers was 1.6 times, and the coefficient of variation was 31.3%. The yield of nut in husk fertilized 4 times per year was up to 8490 kg per hectare. The yield of nut in husk of applying chemical and organic fertilizer was significantly higher than that of only applying organic fertilizer. The yield of nut in husk on young Macadamia trees shaped was 246% higher than that of unmanaged trees, and the yield of pruned trees was 50% higher than that of unmanaged trees. Thrips, rust disease and stink bugs were becoming more and more harmful, which thrips harm reduced nut production by 21.3%, bug harm led to bad nut rate of 0–12.3%, and the average rate was 4.68%. Integrated solution towards efficient production with high quality for Macadamia were put forward. Firstly, to strengthen plantation construction with the soil fertilizer scientific management, shaping and pruning, and controlling pest, and to improve the scientific awareness of forest farmers to improve effectively the nut yield per hectare on Macadamia. Secondly, to strengthen the scientific and technological support, to establish a high quality demonstration plantation with high-standard and efficient production, and to build an efficient technology mode with high quality. Thirdly, to insist on moderate development, to standardize the inputs and to improve the quality and efficiency of the plantation. Lastly, to improve the organization degree, close the interest connection mechanism of forests and farmers, cooperative organizations and leading enterprises.