In a 10-year project, the authors tested the performance of complete tree harvesting as an alternative to mulching in the geometric first thinning of young Mediterranean pine, in flat, sandy soils. In 1998, a simple machine set-up was used to uproot removal trees, chip them, and extract the biomass to a roadside landing. Time study data were collected to obtain reliable estimates of processing productivity and were later turned into harvesting cost figures by applying current machine operating costs. In 2008, the same experimental plots were measured again for tree mortality and growth to determine if the seemingly traumatic process of uprooting had resulted in any major negative impacts. It was concluded that complete tree harvesting is a viable option for the geometric first thinning of young pine plantations: under the conditions of this study, it is preferable to mulching to waste whenever the delivered price of chips exceeds 30 Euro per ton ((sic) t(-1)). Financial sustainability is reached for a chip price in the order of 40 (sic) t(-1). Very intense superthinning (75% removal) offers better financial results than standard heavy thinning (50% removal), and neither option seems to negatively affect residual stand mortality and growth.
Complete tree harvesting as an alternative to mulching in early thinnings
Spinelli R;Magagnotti N;Picchi G
2009
Abstract
In a 10-year project, the authors tested the performance of complete tree harvesting as an alternative to mulching in the geometric first thinning of young Mediterranean pine, in flat, sandy soils. In 1998, a simple machine set-up was used to uproot removal trees, chip them, and extract the biomass to a roadside landing. Time study data were collected to obtain reliable estimates of processing productivity and were later turned into harvesting cost figures by applying current machine operating costs. In 2008, the same experimental plots were measured again for tree mortality and growth to determine if the seemingly traumatic process of uprooting had resulted in any major negative impacts. It was concluded that complete tree harvesting is a viable option for the geometric first thinning of young pine plantations: under the conditions of this study, it is preferable to mulching to waste whenever the delivered price of chips exceeds 30 Euro per ton ((sic) t(-1)). Financial sustainability is reached for a chip price in the order of 40 (sic) t(-1). Very intense superthinning (75% removal) offers better financial results than standard heavy thinning (50% removal), and neither option seems to negatively affect residual stand mortality and growth.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


