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We set out to determine the particle-size distribution, the fiber, the bark and the leaves content, the heating value, the CNH and the ash content of a wide sample of wood chips, collected from 10 forestry and 10 agroforestry production sources. This sampling focused on two main production types: forestry (Full Tree System—FTS—and logging residues—LR) and agroforestry (Short Rotation Coppice—SRC). For the forestry production wood chips from coniferous and broadleaf species were considered. For the agroforestry production wood chips from poplar plantations were examined (different clones with two different harvesting intervals). Overall, we collected 400 samples. Particle size distribution was determined with an automatic screening device on 200 samples. The higher heating value was determined on 200 subsamples using an adiabatic bomb calorimeter. The CNH and the ash content was ascertained on another 200 subsamples. FTS and SRC (with three year old sprouts) offered the best quality, with high fiber content (71%–80%), favorable particle-size distribution and good energetic parameters. On the contrary, both logging residues and SRC (with two year old sprouts) presented a high bark content (18%–27%) and occasionally a mediocre particle-size distribution, being often too rich in fines (6%–12%), but the energetic parameters are in the normal range.

The main aims of this study were to determine the productivity, profitability and energy balance (output/input) of mechanized harvesting applied to a eucalyptus plantation in central Italy. The study area was located in Rome, at an altitude of 35 m a.s.l., on a flat, even site (average slope gradient 3%). The stand was a eucalypt coppice (Eucalyptus camaldulensis Dehnh.) harvested for the first time in 2000. The planting pattern was square with 3 m among stumps (1111 trees ha–1). By 2009, insect (Phorachantha semipunctata) attacks had reduced stump density to 592 stumps ha–1. The work system applied was theWhole Tree System(WTS) and the final assortement chips for energy.Machine rateswere calculated using coefficients and mathematical formulas extracted from themain methodologies proposed by different authors. Energy balance was estimated with the Gross Energy Requirements (GER) method. In these plantations, mechanized harvesting seems most appropriate: this is demonstrated by the high productivity recorded (PSH15 6.5 td.w. h–1 worker–1) and by the favorable energy balance (output/input 23.8, 95.8% system efficiency). However harvesting cost is still high (44.30 € tf.w. –1) and can only be reduced through careful operational planning.