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The study aimed to evaluate the aboveground dry biomass production and the quality of fresh and dried chips obtained by eight different species grown under SRC culture and subjected to two harvesting systems and chipping devices. The present study was part of a long project including different species and management regime of a SRC plantation, which was established in 2007 on a level soil at the Improsta experimental farm (Eboli, Salerno, Italy). In 2015, It was realized a comparative test chipping eight different species grown under SRC system: Fraxinus oxyphylla, Robinia pseudoacacia, Salix alba, Populus nigra (Limatola) and four hybrid genotypes of Populus x euroamericana (Grimminge, Vesten, Hoogvorst, Muur), harvested at the end of the first three years rotation coppice (2012-2014). The trees were chipped both fresh and dried. The fresh biomass was harvested and chipped in a single phase by a self-propelled forage harvester Claas Jaguar 880 (nominal power of 353 kW), equipped with GBE biomass head for trees cutting and harvester feeding. The dried biomass was chipped by a forestry wood disk chipper Farmi Forest CH 260, after two months of storage in the field. The plantation mean of the standing aboveground dry biomass was greater for P. nigra Limatola, followed by F. oxyphylla. As consequences, they showed respectively a high mean annual increment of aboveground dry biomass of 14.38 and 10.16 t ha-1 year-1. The first coppice rotation dry biomass yield was not significantly different for Hoogvorst and Vesten. In contrast to the biometric attributes clone Muur showed a low aboveground dry biomass production, followed by Grimminge and S. alba with a significantly lower production. Moisture content of the fresh biomass ranged between 42.59 % and 56.84 % for black locust and willow, respectively. The dried biomass ranged, instead, between 17.32 % for willow and 36.80 % for Populus nigra. The average reduction of moisture content after storage was 43.97 % with the highest and lowest rate of dehydration for willow (69.53 %) and poplar Vesten (28.70 %). Concerning the particle size distribution, the presence of large chips (63-45 mm) and oversized (> 63 mm) were extremely limited for the fresh chips, while it is considerably higher for the dried chips. Fractions ranging from 45 to 3 mm were the most represented for all species and treatment, accounting between 84.09 % and 90.65 % for the fresh chips, and 74.15 % and 85.68 % for the dried chips. The comminution carried out with the disk chipper on dried biomass always leads to a decrease in the percentage of accept (45-3 mm fractions) respect to the same fresh species chipped by drum chipper.

The aim of this study was to evaluate the performance of two-pass harvesting system on giant reed (Arundo donax). The biomass was shredded, dried in the field and baled for logistic chain and storage. The first step was cutting and grinding biomass crops with a specific shredder rear-mounted on an agricultural tractor. Subsequently, after some days of drying in the field monitoring continuously its moisture content, the Arundo biomass was collected in round-bales for storage. This harvesting system presents the following advantages: immediate and long biomass storage (12-14 % or lower moisture content), better use of farm mechanization for hay making, diversified use of the dried biomass (combustion and II° generation ethanol), reduced fuel consumption (in line or even lower than other ordinary crops present in that area). The tests carried out showed the technical and energy features of the harvest technology based on the adoption of only one specific shredder machine, designed and developed by an Italian constructor for more biomass herbaceous crops (Arundo, Sorghum, Panicum, Mischantus, etc). This machine is suitable for highly vegetative developed crops and can spread the product in all soil surface or windrows. The tests, conducted in the South of Italy (Campania region) in an experimental farm of Torre Lama, showed a good system performance, slightly lower than 1.5 ha h-1 (1.47), with 4.88 km h-1operative speed.

Apricot trees usually bear more fruits than they can adequately support. Crop load adjustment through fruit thinning is a routine practice adopted by fruit growers to obtain a marketable product. Manual thinning, although effective, is a labor-intense and expensive operation, accounting for over 30% of the production costs; chemical thinning, on the other hand, provides inconsistent results and, though relatively inexpensive, is an unreliable practice.The aim of this study is to test a new thinner machine on apricots fruitlets, identifying the most suitable working speed combining thinning with the lack of visible damage on branches and on the remaining fruits. The machine is composed by a rotor equipped with radial rods on a central axe mounted in a rear tree point linkage of a tractor. Trials were carried out in April 2016 in an apricot orchard sited in Cesena (FC). The experiment aimed to compare mechanical thinning at different working speeds (1.11 and 0.83 m s-1) and hand thinning on green fruits (2 ≤ Ø ≤ 2.5 cm). The thinning effect was evaluated by counting the remaining fruits from 40 randomly chosen branches in the upper and down part of four plants replicates. After the mechanical thinning, a manual thinning of finishing was performed, aimed to eliminate the fruits too close together on the branch and, in general, to ensure a uniform fruit set on the tree. The time required for thinning was measured in the mechanically thinned trees and compared with the ones thinned only by hand (control). The two different working speeds gave two different thinning intensities: at 0.83 m s-1 fallen fruits counted for 44 % of the total while 47 % at 1.11 m s-1 . The thinning effects depended on the branch length: the highest fruit reduction was recorded (50.3 %) in more-than-35-cm long branches at 1.11 m s-1 while the lowest one (44.4 %) was recorded in less-than-15-cm long branches. The results obtained in the thesis at 0.83 m s-1 were different. The percentage of fruit reduction varied, indeed, from 47.5 % recorded in more-than-35-cm long branches and 41.3 % recorded in less-than-15-cm long branches. Mechanical thinning can produce a net economic impact on apricot cultivation and, in some cases, can replace manual thinning and reduce the labor costs considerably.