Radiata pine and Douglas-fir plantations in New Zealand

• Autores: Peri, Pablo Luis
• Año de publicación: 1999
• Idioma: inglés
• Tipo de recurso: informe técnico
• Fuente: Publicación Técnica Forestal / EEA Santa Cruz; nº 16 (1999)
• Materia: Pinus radiata; Plantaciones; Mejora Genética; Esquejado; Plantations; Genetic Improvement; Propagation by Cuttings; Plantation Forestry; Competing Vegetation; Plantaciones Forestales; Vegetación Competidora
• Institución: Instituto Nacional de Tecnología Agropecuaria

Douglas-fir makes up almost 5% of New Zealand’s plantation forest, and with 60,000 ha planted is the second most common species after radiata pine with 1.6 million ha. Genetic improvement is one important aspect of intensive plantation forestry. Three basic phases of practical genetic improvement of forest trees was considered: selection of species, selection of provenances within species and selection of and breeding from individuals within suitable provenances of species. The gain in percentage of acceptable stems mean that improved seedlots require fewer seedlings to be planted per hectare and less thinning-to-waste than “bulk” seed, to obtain the same number of crop trees. Also the gain in form, combined with volume gains, result in large increases in log values. By far the main intensive breeding effort based on individual-treeselection has been devoted to P. radiata than to Douglas-fir. To take full advantage of the available improved seed, methods of propagating cuttings from 1-year-old radiata pine seedlings have been developed in New Zealand. While radiata pine performs well over a wide range of sites in New Zealand, Douglas-fir is now recognised as the most appropriate choice for many mid- and high elevation sites where increased effects of exposure must be tolerated. Correct site preparation is often essential to the success of the plantation. Before planting, site preparation is carried out to control competing vegetation and remove debris, and also to assist root penetration where is needed. Compared with Douglas-fir, radiata pine generally has a high tolerance of competing vegetation. Current practice in New Zealand for radiata pine to plant 600 to 1000 trees per hectare (bare-rooted), depending on regime and terrain, thinning in two operation to 250-400 spha final stocking. Extreme regimes are for agroforestry (100-200 spha, up to 3-4 pruning lifts and 3 waste thinning), and for pulp production 1500-1600 spha, and no thinning. Low (less than 1300 spha) or irregular initial stocking may permit excessive branch diameters on Douglas-fir. A great number of combinations are possible between initial stocking, timing and intensity of pruning and thinning, and final crop stocking. Management and market circumstances will differ and there is probably a good solution to fit every case. Because of its good strength and stability New Zealand grown Douglas-fir is primarily suited for use as a structural and framing timber. Radiata pine is grown mainly for its wood, which is processed into sawn timber, plywood, and reconstituted products (chipboard and particle board).
EEA Santa Cruz
Fil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina
Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral (UNPA); Argentina