| 1. |
- Edelfeldt, Stina, et al.
(författare)
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Effects of cutting traits and competition on performance and size hierarchy development over two cutting cycles in willow
- 2018
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 108, s. 66-73
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Tidskriftsartikel (refereegranskat)abstract
- To assess if cutting traits (clone, fresh weight) in combination with strong competition from adjacent willows (planted in monoclonal stands and clonal mixtures) affected performance and size hierarchy development in willow during consecutive harvests, a field experiment was performed in central Sweden during 2008-2015. Cuttings from five Salix clones were planted in 1.8 m x 1.8 m plots, at a density of 197 500 cuttings ha(-1) in monoculture and in ten mixtures using two clones (i.e. 15 combinations). Maximum height was measured each year and the experiment was harvested after the growing seasons 2012 and 2014. Larger cuttings produced stools with lower death rate, higher maximum height and larger biomass production compared to smaller cuttings. The high competition pressure resulted in 9.2% stool death at harvest 2012 and 39% stool death at harvest 2014. Tora (Salix schwerinii x Salix viminalis) showed the highest performance and Jorr (Salix viminalis) and Gudrun (Salix dasyclados) the lowest. Planting system had less effect on stool death, height development and biomass production. Tora was the only clone producing more biomass when grown in mixtures compared to monoculture. The size hierarchy between individual stools was generally kept during the experimental period in both monocultures and mixtures, even if the height correlations decreased with year. To obtain a more even establishment of willow stands and lower the risk of a size hierarchy developing leading to large stool mortality and gaps in the stand, we recommend the use of larger and more even-sized cuttings.
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| 2. |
- Edelfeldt, Stina, et al.
(författare)
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Effects of mechanical planting on establishment and early growth of willow
- 2013
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Ingår i: Biomass and Bioenergy. - : Elsevier BV. - 0961-9534 .- 1873-2909. ; 55, s. 234-242
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Tidskriftsartikel (refereegranskat)abstract
- Commercial willow planting is mostly performed by machines, using long rods which are automatically pressed in the soil and cut. This procedure exerts a large mechanical impact on the cuttings, and may lead to damage, especially when planted in compacted soils. We studied cuttings and early growth performance of willow (in terms of produced shoot biomass, shoot height, leaf area, and number of shoots per cutting) after machine planting, in comparison to manually prepared and planted cuttings. To isolate the effect of mechanical planting from the effects of field variation after planting, we dug out cuttings from five different clones directly after machine planting in well prepared and compacted soil respectively and grew them under controlled conditions, together with a manually prepared control. We found that undamaged cuttings had a better growth performance than visibly damaged cuttings. Planting by machine on compacted soil resulted in a relatively large number of cuttings landing on the soil surface, instead of being planted vertically in the soil. Soil compaction and machine planting interacted with cutting dimensions, the poorer performance of thinner cuttings being more pronounced in compacted soil. To obtain a faster and more even establishment of willows, we recommend thorough soil cultivation prior to planting, further development of planting machines to minimize damage to cuttings at planting, and the use of cuttings with a diameter of at least 10-11 mm. (C) 2013 Elsevier Ltd. All rights reserved.
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