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An increase in Short Rotation Forestry (SRF) in Ireland is expected in response to the increasing demand for fibre products and wood energy. SRF is the practice of cultivating fast growing tree species mainly for the production of biomass, through a rotation length of less than 20 years in Ireland. Although forest policy is promoting SRF, currently establishment is limited. This thesis aims to investigate the potential financial value of practicing SRF and evaluate whether SRF should be financially managed to allocate a range of assortments to diverse markets or supply a single market only. The work included: 1) Quantification of above ground biomass by dry matter content, merchantable volume and energy content from four SRF stands, two of Eucalyptus spp. and two of Populus spp.; 2) A market survey identifying pallet producers and the wood energy sector as most willing to use SRF material; 3) Benchmarking conditions that facilitated market development in Oregon with current conditions in Ireland, identifying: large scale plantations; high value product market development; and, investment in research, education and marketing, as key conditions; 4) Development of a unit conversion tool to quantify and value wood resources by volume, weight and energy parameters for market segment comparison and 5) Determination, from the landowner’s perspective, of the optimal financial value of SRF and finding maximum returns were for eucalyptus stands used for diverse markets, mainly small sawlog for pallet production. Contrary to policy objectives, SRF will not contribute significant biomass to fibre and fuel markets, under current financial and market conditions. Policy promoting SRF must be long term, and supported by industry, research and education to gain landowners acceptance. Further research on SRF wood properties and yield models will be necessary to underpin SRF development in Ireland.

A comprehensive study of a number of in-forest wood energy supply chains was undertaken to collect empirical data on many aspects of both the stand and operational parameters therein. The data was then used to develop statistical models, so that a number of harvesting systems could be compared in a simulated environment. The simulated environment had two factors: the mean diameter at breast height (dbh) of the stand (cm), and the mean extraction distance (m). The harvesting systems compared were: cut to length (CTL) harvesting, CTL harvesting with chipping of the pulp assortment, and whole tree harvesting with terrain chipping of the whole trees. Not only were models developed on the productivity of the machines, but a taper equation, dbh to total height model, and a set of dbh distribution models were developed to predict the volumes of the assortments attributable to each harvesting system down to the tree level. The productivity models then used this data to estimate a cost of production per hectare for the harvesting systems. A value per unit volume of the assortments was taken from literature, and a profit analysis performed for each harvesting system. The simulation results show that whole tree harvesting and terrain chipping returns the highest positive profit for all levels of mean dbh at short extraction distances, but suffered from the machine interaction in the terrain chipping system at long extraction distances. The machine interaction between the terrain chipper and the chips forwarder was analysed using discrete event simulations. CTL harvesting and chipping of the pulp assortment returned the highest positive profit at longer extraction distances.