Comparing hybrid Populus clones for SRF across northern Italy after two biennial rotations: Survival, growth and yield

Abstract Short rotation forest (SRF) plantations of hybrid poplars are attractive for Italian farmers due to the availability of public grants and the potential for producing wood chips for energy production. Growth and dendromass yield of new clones for SRF were evaluated after two biennial rotations within a network of experimental fields established in 2003 on three sites of low (Bigarello), medium (Vinovo) and high soil quality (Mira), across northern Italy. Soil preparation, planting density (5900 trees ha −1 ), weed control, tree water status and mechanical harvesting were homogeneous across the sites. Nitrogen fertilization was applied only in Mira (300 kg N ha −1 ). In all sites, survival was high for almost all clones, and stem density increased dramatically, with a decrease of stem dimensions, after the first coppicing. In Bigarello, with limiting soil conditions, there was no significant difference among clone biennial yields, which varied from 10.3 (first rotation) to 14.2 (second rotation) Mg ha −1 in dry matter (dm). In the medium and high quality sites of Vinovo and Mira, there was a significant difference in clone yields, with the new clones performing better than control clones (I-214 and Lux). In Mira, mean biennial yield increased from 30.2 to 40.3 Mg dm ha −1 from the first to second cycle. Preliminary results of new clones on medium and high soil quality need to be further confirmed throughout further coppicing cycles; on a marginal soil, even by using the new clones, poplar SRF is not an advisable option.

[1]  D. B. Duncan.  MULTIPLE RANGE AND MULTIPLE F TESTS , 1955 .

[2]  Gianfranco Minotta,et al.  Identification of the main site factors and management intensity affecting the establishment of Short-Rotation-Coppices (SRC) in Northern Italy through stepwise regression analysis , 2010, Central European Journal of Biology.

[3]  Ronald S. Zalesny,et al.  Early rooting of dormant hardwood cuttings of Populus: analysis of quantitative genetics and genotype x environment interactions , 2005 .

[4]  W. T. Bagley,et al.  Variation in rooting capability of Populus deltoides. , 1977 .

[5]  R. McLaughlin,et al.  Biomass and nitrogen dynamics of hybrid poplar on two different soils: implications for fertilization strategy , 1988 .

[6]  Raoul Lemeur,et al.  Short-rotation forestry of birch, maple, poplar and willow in Flanders (Belgium) I—Biomass production after 4 years of tree growth , 2007 .

[7]  A. DesRochers,et al.  A comparison of pre-planting treatments on hardwood cuttings of four hybrid poplar clones , 2003, New Forests.

[8]  Enrico Bonari,et al.  Comparison of Arundo donax L. and Miscanthus x giganteus in a long-term field experiment in Central Italy: Analysis of productive characteristics and energy balance , 2009 .

[9]  Gianfranco Minotta,et al.  Indirizzi colturali e valorizzazione delle produzioni legnose fuori foresta , 2009 .

[10]  I. Tubby,et al.  Effects of spacing and cutting cycle on the yield of poplar grown as an energy crop , 1999 .

[11]  Wayne A. Geyer,et al.  Biomass production in the Central Great Plains USA under various coppice regimes , 2006 .

[12]  L. Christersson,et al.  Short-rotation forestry - a complement to "conventional" forestry. , 2006 .

[13]  T. McMahon,et al.  Updated world map of the Köppen-Geiger climate classification , 2007 .

[14]  Olivier Dupont,et al.  Heat and drought 2003 in Europe: a climate synthesis , 2006 .

[15]  R. Ceulemans,et al.  Linear and non-linear functions of volume index to estimate woody biomass in high density young poplar stands , 1997 .

[16]  F Facciotto,et al.  Produttività di cloni di pioppo e salice in piantagioni a turno breve , 2006 .

[17]  T. Vesala,et al.  Reduction of ecosystem productivity and respiration during the European summer 2003 climate anomaly: a joint flux tower, remote sensing and modelling analysis , 2007 .

[18]  E. Bonari,et al.  Estimation of chemical traits in poplar short-rotation coppice at stand level , 2009 .

[19]  M. Tomé,et al.  Models of potential height and diameter for Eucalyptus globulus in Portugal , 2003 .

[20]  L. Rytter.  Nutrient content in stems of hybrid aspen as affected by tree age and tree size, and nutrient removal with harvest. , 2002 .

[21]  M. Manzone,et al.  Energetic and economic evaluation of a poplar cultivation for the biomass production in Italy. , 2009 .

[22]  T. Tschaplinski,et al.  Nitrogen fertilization strategies in a short-rotation sycamore plantation , 1994 .

[23]  B. Rudolf,et al.  World Map of the Köppen-Geiger climate classification updated , 2006 .

[24]  R. Ceulemans,et al.  Dynamics of biomass production in a poplar coppice culture over three rotations (11 years) , 2008 .

[25]  E. Bonari,et al.  Water requirements of poplar and willow vegetation filters grown in lysimeter under Mediterranean conditions: Results of the second rotation , 2009 .

[26]  Blas Mola-Yudego,et al.  Yield models for commercial willow biomass plantations in Sweden , 2008 .

[27]  E. Bonari,et al.  Evapotranspiration and crop coefficient of poplar and willow short-rotation coppice used as vegetation filter. , 2008, Bioresource technology.