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M. Carneiro - One of the best experts on this subject based on the ideXlab platform.
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do Harrowing and fertilisation at middle rotation improve tree growth and site quality in eucalyptus globulus labill plantations in mediterranean conditions
European Journal of Forest Research, 2012Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (<13.4 g m−2) than other treatments (33−61 g m−2) during the first 3 years, but at the end of the experiment differences were less important. Forest floor litter mass after 3 years and at the end of the experiment were similar among treatments. Soil bulk density significantly decreased by Harrowing (H and HF treatments), but 16 months after treatments were similar. Although soil chemical properties were not significantly affected by treatments, a decrease in base cations occurred during the rotation period. Fertiliser application is a questionable practice under the economic point of view, whereas Harrowing can reduce the fuel load only during a short period, without negative effects on productivity and soil quality.
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Do Harrowing and fertilisation at middle rotation improve tree growth and site quality in Eucalyptus globulus Labill. plantations in Mediterranean conditions
European Journal of Forest Research, 2011Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (
Jesper Rasmussen - One of the best experts on this subject based on the ideXlab platform.
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timing of post emergence weed Harrowing
Weed Research, 2010Co-Authors: Jesper Rasmussen, Helle Mathiasen, Bo Martin BibbyAbstract:The timing of post-emergence weed Harrowing was evaluated for two years in spring barley with crop-weed selectivity and crop recovery as the key parameters measured. Selectivity describes the relationship between weed control and crop soil cover immediately after Harrowing, with crop soil cover as the percentage of the crop that has been covered by soil due to Harrowing. Crop recovery describes the relationship between crop yield loss and crop soil cover in the absence of weeds. Neither selectivity nor crop recovery was affected by timing within a period of two weeks in the early growth stages of spring barley. Selectivity was unaffected by year and 80% weed control was associated with crop soil cover in the range of 23-33%, for all combinations of year and growth stage. Crop recovery was affected by year, with an average crop yield loss of 3.5% caused by 25% crop soil cover in 2007 and complete recovery in 2008. A detailed study of crop growth and weed density in the period just after Harrowing, showed that the recovery processes of crop and weeds were influenced by timing of Harrowing, but this had no impacts on crop yield. In conclusion, timing of post-emergence weed Harrowing was not found to be crucial, given the condition that the aggressiveness of cultivation was adjusted to the growth stage.
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Timing of post‐emergence weed Harrowing
Weed Research, 2010Co-Authors: Jesper Rasmussen, Helle Mathiasen, Bo Martin BibbyAbstract:The timing of post-emergence weed Harrowing was evaluated for two years in spring barley with crop-weed selectivity and crop recovery as the key parameters measured. Selectivity describes the relationship between weed control and crop soil cover immediately after Harrowing, with crop soil cover as the percentage of the crop that has been covered by soil due to Harrowing. Crop recovery describes the relationship between crop yield loss and crop soil cover in the absence of weeds. Neither selectivity nor crop recovery was affected by timing within a period of two weeks in the early growth stages of spring barley. Selectivity was unaffected by year and 80% weed control was associated with crop soil cover in the range of 23-33%, for all combinations of year and growth stage. Crop recovery was affected by year, with an average crop yield loss of 3.5% caused by 25% crop soil cover in 2007 and complete recovery in 2008. A detailed study of crop growth and weed density in the period just after Harrowing, showed that the recovery processes of crop and weeds were influenced by timing of Harrowing, but this had no impacts on crop yield. In conclusion, timing of post-emergence weed Harrowing was not found to be crucial, given the condition that the aggressiveness of cultivation was adjusted to the growth stage.
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Weed Harrowing and inter-row hoeing in organic grown quinoa (Chenopodium quinoa Willd.)
Outlook on Agriculture, 2010Co-Authors: Sven-erik Jacobsen, Jørgen Lindskrog Christiansen, Jesper RasmussenAbstract:Weeds, with their negative influence on both yield and quality, constitute a major problem in the organic production of quinoa, a potential new seed crop for protein feed and human consumption in Europe. To attain effective weed control, mechanical weeding strategies, such as weed Harrowing and inter-row hoeing, were studied. Weed Harrowing operates over the entire plot with flexible tines, affecting both crop and weeds, whereas inter-row hoeing is performed between the rows, aiming only at the weeds. The study showed that both hoeing and Harrowing reduced the quinoa density in one out of two years, whereas there was no effect on quinoa density in the other year. Yield was increased by both methods, but hoeing increased yield more than Harrowing due to better weed control. Regression analysis showed that crop yield was related to weed dry matter and showed no indications of higher crop damage associated with weed Harrowing. Protein content was low when weeds were not treated, and increased significantly w...
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Digital image analysis offers new possibilities in weed Harrowing research
2006Co-Authors: Jesper Rasmussen, Michael NørremarkAbstract:Two field experiments were carried out in winter wheat to determine the optimal intensity and timing of weed Harrowing. Each experiment was designed to create a series of intensities by increasing the number of passes at varying growth stages. Visual assessments and digital image processing were used to assess crop soil cover associated with weed Harrowing. The study showed that winter wheat responded differently to weed Harrowing at different growth stages. In autumn, the crop was severely damaged due to high degrees of crop soil cover and poor recovery resulting in crop yield losses in the range of 7 % to 22 %. In early spring, the crop showed some variability in the ability to recover from soil cover. The best results in spring were obtained at growth stage 22 (BBCH). Increasing number of passes resulted in increasing crop yields in the range of 2 % to 5 % and increasing degrees of weed control in the range of 22 % to 62 %. The role of digital image analysis in future weed Harrowing research is discussed.
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Selectivity of weed Harrowing in lupin
Weed Research, 2004Co-Authors: Rikke K. Jensen, Jesper Rasmussen, Bo MelanderAbstract:Three field experiments were conducted in lupin in 1997, 1998 and 1999 to study two aspects of selectivity of post-emergence weed Harrowing; the ability of the crop to resist soil covering (the initial damage effect), and the ability of the crop to tolerate soil covering (the recovery effect). Each year soil covering curves and crop tolerance curves were established in three early growth stages of lupin. Soil covering curves connected weed control and crop soil cover in weedy plots, and crop tolerance curves connected crop yield and crop soil cover in weed-free plots. The experiments showed that both resistance and tolerance were unaffected by the growth stage of lupin within the range from the cotyledon to the 7 to 8 leaf growth stages. Tolerance to soil covering was also unaffected by year whereas the ability of the crop to resist soil covering was highly affected by year. Lupin showed high tolerance to soil covering but a rather low ability to resist soil covering. Harrowing at multiple growth stages supported the finding that lupin is fairly tolerant to soil covering. Advantages and disadvantages of using soil covering as a measure of crop damage is discussed. In conclusion, weed Harrowing in lupin showed positive prospects due to high tolerance to crop soil cover.
Manuel Madeira - One of the best experts on this subject based on the ideXlab platform.
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do Harrowing and fertilisation at middle rotation improve tree growth and site quality in eucalyptus globulus labill plantations in mediterranean conditions
European Journal of Forest Research, 2012Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (<13.4 g m−2) than other treatments (33−61 g m−2) during the first 3 years, but at the end of the experiment differences were less important. Forest floor litter mass after 3 years and at the end of the experiment were similar among treatments. Soil bulk density significantly decreased by Harrowing (H and HF treatments), but 16 months after treatments were similar. Although soil chemical properties were not significantly affected by treatments, a decrease in base cations occurred during the rotation period. Fertiliser application is a questionable practice under the economic point of view, whereas Harrowing can reduce the fuel load only during a short period, without negative effects on productivity and soil quality.
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Do Harrowing and fertilisation at middle rotation improve tree growth and site quality in Eucalyptus globulus Labill. plantations in Mediterranean conditions
European Journal of Forest Research, 2011Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (
António Fabião - One of the best experts on this subject based on the ideXlab platform.
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do Harrowing and fertilisation at middle rotation improve tree growth and site quality in eucalyptus globulus labill plantations in mediterranean conditions
European Journal of Forest Research, 2012Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (<13.4 g m−2) than other treatments (33−61 g m−2) during the first 3 years, but at the end of the experiment differences were less important. Forest floor litter mass after 3 years and at the end of the experiment were similar among treatments. Soil bulk density significantly decreased by Harrowing (H and HF treatments), but 16 months after treatments were similar. Although soil chemical properties were not significantly affected by treatments, a decrease in base cations occurred during the rotation period. Fertiliser application is a questionable practice under the economic point of view, whereas Harrowing can reduce the fuel load only during a short period, without negative effects on productivity and soil quality.
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Do Harrowing and fertilisation at middle rotation improve tree growth and site quality in Eucalyptus globulus Labill. plantations in Mediterranean conditions
European Journal of Forest Research, 2011Co-Authors: Manuel Madeira, António Fabião, M. CarneiroAbstract:Effects of Harrowing and fertilisation on tree growth, understory vegetation, forest floor litter and soil properties were studied in a field experiment installed in a 5-year-old first rotation eucalypt plantation. The treatments were Harrowing (H), fertilisation (F), Harrowing and fertilisation (HF) and a control without any treatments (C), with four replicates. Tree growth, root mass, tree nutrition status, understory vegetation, mass of forest floor litter and soil physical and chemical properties were monitored till the end of the rotation (stand was 14-year old). Effects of treatments on tree growth, root mass and timber production were not significant. Root nutrient concentration differed between treatments only few months after the beginning of the experiment, while differences regarding specific root length and area were observed during the first year. Harrowing (H and HF) led to significantly smaller biomass of understory vegetation (
Hugh Riley - One of the best experts on this subject based on the ideXlab platform.
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method timing and duration of bare fallow for the control of cirsium arvense and other creeping perennials
Crop Protection, 2015Co-Authors: Hugh Riley, Mette Goul Thomsen, Kjell Mangerud, Lars Olav BrandsaeterAbstract:Abstract The control of perennial weeds is of great concern in organic farming. Mouldboard ploughing and other soil tillage operations are the main methods for combating weeds, often combined with competition from a green manure cover crop. Inclusion of a period with bare fallow may at times become necessary. Repeated soil tillage may however cause erosion and loss of nutrients, more so with autumn tillage than with spring tillage. The timing and effectiveness of the operations are therefore important. The aim of the present work has been to evaluate if autumn ploughing contributes to increased weed reduction if spring fallow is performed, how to combine stubble cultivation, fallow and establishment of a green manure cover-crop and to compare the two and the optimum duration of spring fallow compared to an established green manure cover-crop. The effectiveness of operations varied between weed species and was related to their biology. Overall, the perennial species studied developed least total biomass in a mown, one-year green manure crop or after complete underground cutting by shallow ploughing after harvest or by deep ploughing in spring. The green manure cover-crop seemed to be established most successfully after stubble Harrowing in autumn and spring or when undersown the previous year. Autumn ploughing had little impact on the biomass of perennial weeds when spring bare fallow treatments were performed or when a green manure cover-crop was established in spring. Only a high number of Harrowings competed well with the undersowing of a green manure cover-crop for the regulation of the individual species, except in the case Elymus repens . The number of fallow operations may be kept to a minimum when followed by a green manure cover-crop, or when such a crop is undersown the previous year. If fallowing in spring is performed, we found no benefit from increasing the number of fallow operations from three to four Harrowings. Shallow ploughing after harvest followed by tine Harrowing in autumn reduced total perennial weed biomass to the same extent as two or three Harrowings in spring without subsequent ploughing, or two Harrowings in spring followed by ploughing. We found in general an increase in cereal yield with the inclusion of a green manure cover crop, preferably undersown in the first experimental year. A prolonged period with fallow treatments had a negative effect on the cereal yield and the number of spring operations for optimization of cereal yield was lower than that required for optimum weed control. We need therefore to find a balance between these two factors.
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Verification of traffic-induced soil compaction after long-term ploughing and 10 years minimum tillage on clay loam soil in South-East Norway
Acta Agriculturae Scandinavica Section B-soil and Plant Science, 2014Co-Authors: T. Seehusen, Trond Børresen, B.i. Rostad, Heiner Fleige, Alexander Zink, Hugh RileyAbstract:Grain yields are presented from a 10-year field trial with four tillage regimes (annual ploughing, Harrowing only, ploughing/Harrowing alternate years and minimum tillage) on clay loam. We also present soil physical analyses and use the compaction verification tool (CVT) to assess compaction on plots with annual ploughing and minimum tillage, after using slurry tankers with contrasting wheel loads (4.1 Mg, 6.6 Mg) and wheeling intensities (1×/10×) in the 11th trial year, and yields monitored two years after compaction. Winter wheat yields in the period before compaction were strongly affected by tillage, with annual ploughing giving on average 24% higher yield than direct drilling. Both wheat and oats were far less affected in treatments with Harrowing only or ploughing/Harrowing alternate years, on average within 6% of annual ploughing. Yields after compaction were affected by both previous tillage and compaction intensity. In the first year, single wheeling after annual ploughing gave 23% yield reductio...
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Recent yield results and trends over time with conservation tillage on clay loam and silt loam soils in southeast Norway
Acta Agriculturae Scandinavica Section B - Plant Soil Science, 2009Co-Authors: Hugh Riley, Trond Børresen, Per Ove LindemarkAbstract:Abstract Yields are reported from four long-term (16–30 years) tillage trials, comparing results since 1998, under relatively wet conditions, with earlier experience. In trial 1, on clay loam, mean grain yield with spring Harrowing only, has since 1998 been 87% of that obtained with autumn ploughing, whereas it was 94% for the whole period since 1991. The inclusion of autumn Harrowing increased these figures to 94 and 98%, respectively. Over the last six years, spring ploughing gave 5% lower yield than did autumn ploughing. Relative yields of unploughed versus ploughed treatments were negatively correlated with summer rainfall. Grain protein was lowest with spring Harrowing only. In trial 2, on clay loam, direct drilling has since 1998, as in previous years, given around 10% lower yield than has autumn ploughing. Autumn Harrowing gave 4% lower yield in winter wheat and 6% higher yield in spring oats than did autumn ploughing, whilst yields of spring turnip rape were not significantly affected by tillage. ...
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effects of alternative tillage systems on soil quality and yield of spring cereals on silty clay loam and sandy loam soils in the cool wet climate of central norway
Soil & Tillage Research, 2005Co-Authors: Hugh Riley, Marina Azzaroli Bleken, S Abrahamsen, A K Bergjord, Anne Kjersti BakkenAbstract:Abstract Tillage trials were established on a poorly drained silty loam overlying silty clay loam and on a freely drained sandy loam overlying medium sand, in 1988 and 1989, respectively. Autumn and spring ploughing and two ploughless systems were compared for 12–13 years, with three replications at each site. The ploughless treatments comprised deep versus shallow spring Harrowing until 1999, and thereafter autumn plus spring Harrowing versus spring Harrowing only. In 6 years, treatments with and without fungal spraying of the cereal crops were included. In other years, fungicides were not used. Perennial weeds were controlled by herbicides as necessary, on nine occasions up until 2001. Average spring barley ( Hordeum vulgare L.) and spring oat ( Avena sativa L.) yields were similar with spring ploughing as with autumn ploughing at both sites. In treatments without ploughing, average yields on the silty loam over clay were 93% of those obtained with ploughing, and on the sandy loam over sand they were 81%. Smaller and non-significant yield differences were found between spring Harrowing versus deep spring Harrowing, and between autumn plus spring Harrowing versus spring Harrowing only. Fungal spraying increased yields markedly at both sites (25%), but there was no significant interaction between this treatment and tillage system. Oat was compared with barley in 2 years, with oat performing better under ploughless tillage. At both sites increases in penetrometer resistance occurred in the topsoil of unploughed treatments. These were considered particularly limiting on the sandy loam. On the silty loam there was an increase in surface horizon porosity in the absence of ploughing, which was associated with an increase in topsoil organic matter content. On this soil there was also a tendency toward lower penetrometer resistance at >30 cm depth on autumn plus spring harrowed soil than on ploughed soil, indicating that the plough pan may have diminished. This was supported by observations of greater earthworm activity on unploughed soil. Soil chemical analyses revealed that mineral N and plant-available P and K accumulated in the upper horizon under ploughless tillage. The percentage yields obtained in individual years with autumn as opposed to spring ploughing, were positively correlated with air temperature during 0–4 weeks after planting on the silty loam, and with precipitation during 0–12 weeks after planting on the sandy loam. In the case of yields obtained with spring Harrowing only, relative to spring ploughing, positive correlations were found with 0–4 week temperature on both soil types, suggesting that low early season temperatures may limit yields under ploughless tillage.
