• Authors:
    • Schoenau, G.
    • Tabil, L.
    • Adapa, P.
  • Source: Biosystems Engineering
  • Volume: 104
  • Issue: 3
  • Year: 2009
  • Summary: Agricultural biomass has the potential to be used as feedstock for biofuel production. However, crop residue after harvest must be gathered, processed and densified in order to facilitate efficient handling, transportation and usage. in this study compacts were prepared by densifying material against a base plate (representing the specific energy required to overcome friction within the straw grinds) as opposed to the process that occurs in a commercial operation where compacts are formed due to back-pressure effect in the die. Densification was measured using four selected biomass samples (barley, canola (oilseed rape), oat and wheat straw) at 10% moisture content (wb) and 1.98 mm grinder screen size using a compaction apparatus which applied four pressure levels of 31.6, 63.2, 94.7 and 138.9 MPa. The specific energy required to extrude the compact was measured; this will closely emulate the specific energy required to overcome the friction between the ground straw and die. The mean densities of barley, canola, oat and wheat straw compacts ranged from 907 +/- 31 to 988 +/- 26 kg m(-3), 823 +/- 73 to 1003 +/- 21 kg m(-3), 849 +/- 22 to 1011 +/- 54 kg m(-3) and 813 +/- 55 to 924 +/- 23 kg m(-3), respectively; while the mean total specific energy for compaction of grinds ranged from 3.69 +/- 0.28 to 9.29 +/- 0.39 MJ t(-1), 3.31 +/- 0.82 to 9.44 +/- 0.33 MJ t(-1), 5.25 +/- 0.42 to 9.57 +/- 0.83 MJ t(-1) and 3.59 +/- 0.44 to 7.16 +/- 0.40 MJ t(-1), respectively. Best predictor equations having highest coefficient of determination values (R(2)) and standard error of estimate or root mean square error were determined for both compact density and total specific energy required to compress the ground straw samples. The resulting R 2 for pellet density from barley, canola, oat and wheat straw were 0.56, 0.79, 0.67 and 0.62, respectively, and for total specific energy the values of R 2 were 0.94, 0.96, 0.90 and 0.92, respectively. (C) 2009 IAgrE. Published by Elsevier Ltd. All rights reserved.
  • Authors:
    • Raus, L.
    • Bucur, D.
    • Jitareanu, G.
    • Ailincai, C.
    • Ailincai, D.
    • Zbant, M.
  • Source: Cercetări Agronomice în Moldova
  • Volume: 42
  • Issue: 2
  • Year: 2009
  • Summary: The influence of long-term fertilization and irrigation on wheat and maize yield and soil fertility was studied at the Agricultural Research and Development Station of Podu-Iloaiei since 1980. These experiments were carried out on a 10% slope field, on a Cambic Chernozem with clayey loam texture (423 g clay, 315 g loam and 262 g sand), a neuter to weakly acid reaction and a mean nutrient supply. The mean annual rainfall amounts, recorded in the last 28 years, were higher, with values comprised between 12.7 and 279.2 mm, compared to the multiannual mean on 80 years (542 mm) in 16 years, and lower by 25.3-236.7 mm in 10 years. Annual application of rates of N 160 P 80, in a four-year crop rotation (soybean-wheat-sugar beet-maize)+a reserve field, cultivated with legumes and perennial grasses, determined the accumulation of a reserve of mobile phosphates of 78 mg/kg soil. Under irrigated, a good plant supply with mineral elements and the increase in the content of organic carbon from soil were done by applying the rate of N 80P 70+30 t/ha manure. Nitrogen and phosphorus fertilizers, although applied at high rates (N 130+100 P 2O 5), could not prevent the decrease in organic carbon content from soil.
  • Authors:
    • Griffis, T. J.
    • Baker, J. M.
  • Source: Agricultural and Forest Meteorology
  • Volume: 149
  • Issue: 12
  • Year: 2009
  • Summary: Climate change and economic concerns have motivated intense interest in the development of renewable energy sources, including fuels derived from plant biomass. However, the specter of massive biofuel production has raised other worries, specifically that by displacing food production it will lead to higher food prices, increased incidence of famine, and acceleration of undesirable land use change. One proposed solution is to increase the annual net primary productivity of the existing agricultural land base, so that it can sustainably produce both food and biofuel feedstocks. This might be possible in corn and soybean production regions through the use of winter cover crops, but the biophysical feasibility of this has not been systematically explored. We developed a model for this purpose that simulates the potential biomass production and water use of winter rye in continuous corn and corn-soybean rotations. The input data requirements represent an attempt to balance the demands of a physically and physiologically defensible simulation with the need for broad applicability in space and time. The necessary meteorological data are obtainable from standard agricultural weather stations, and the required management data are simply planting dates and harvest dates for corn and soybeans. Physiological parameters for rye were taken from the literature, supplemented by experimental data specifically collected for this project. The model was run for a number of growing seasons for 8 locations across the Midwestern USA. Results indicate potential rye biomass production of 1-8 Mg ha(-1), with the lowest yields at the more northern sites, where both PAR and degree-days are limited in the interval between fall corn harvest and spring corn or soybean planting. At all sites rye yields are substantially greater when the following crop is soybean rather than corn, since soybean is planted later. Not surprisingly, soil moisture depletion is most likely in years and sites where rye biomass production is greatest. Consistent production of both food and biomass from corn/winter rye/soybean systems will probably require irrigation in many areas and additional N fertilizer, creating possible environmental concerns. Rye growth limitations in the northern portion of the corn belt may be partially mitigated with aerial seeding of rye into standing corn. Published by Elsevier B.V.
  • Authors:
    • Bolotova, N. S.
  • Source: Kormoproizvodstvo
  • Issue: 12
  • Year: 2009
  • Summary: Techniques and standards for production of haylage and silage from high-protein fodder mixtures of pea, oat, rape, vetch, barley, beans, rye, wheat and maize are discussed. Plants should be cut into 15-20 mm pieces when the protein content of fodder mixture is over 30%, and into 40-50 mm pieces when the protein content of fodder mixture is less than 20%. Bales of silage mass are wrapped in film and roll size is 1.2 m wide and 0.8-1.6 m in diameter. The high yield of maize, vetch, and oat-rape mixture achievable in the conditions of European Russia is 10.8 t/ha of dry mass and 1.2 t/ha of protein.
  • Authors:
    • [Anonymous]
  • Source: Muhle + Mischfutter
  • Volume: 145
  • Issue: 18
  • Year: 2008
  • Summary: The article describes harvest and yield details of the German cereals season 2008. All federal states of Germany are covered and all cereals including milling, feed, industrial and grain maize, but excluding silage and corn-cob-mix maize. In 2008, the total tonnage increased from 23% to 49 million tonnes. The highest yield increases, compared to the poor year 2007, were reported from the northern states, Mecklenburg-Vorpommern, Niedersachsen, Schleswig-Holstein and Nordrhein-Westfalen. Average winter wheat yields were 8.1 t/ha, winter barley 6.6 t/ha and triticale 6.0 t/ha. Spring barley was 4.9 t/ha and oats only 4.6 t/ha. Because of the large quantities, enough good quality milling wheat will be available. An outlook on the EU cereal harvest, the global and USA harvests in 2008 are given at the end of the paper.
  • Authors:
    • Shirriff, S.
    • Lozinski, C.
    • Holzgang, G.
    • Hall, L.
    • Brenzil, C.
    • Thomas, A.
    • Leeson, J.
    • Beckie, H.
  • Source: Weed Technology
  • Volume: 22
  • Issue: 3
  • Year: 2008
  • Summary: Weed resistance monitoring has been routinely conducted in the Northern Great Plains of Canada (Prairies) since the mid-1990s. Most recently, random surveys were conducted in Alberta in 2001, Manitoba in 2002, and Saskatchewan in 2003 totaling nearly 800 fields. In addition, nearly 1,300 weed seed samples were submitted by growers across the Prairies between 1996 and 2006 for resistance testing. Collected or submitted samples were screened for group 1 [acetyl-CoA carboxylase (ACCase) inhibitor] and/or group 2 [acetolactate synthase (ALS) inhibitor] resistance. Twenty percent of 565 sampled fields had an herbicide-resistant (HR) wild oat biotype. Most populations exhibited broad cross-resistance across various classes of group 1 or group 2 herbicides. In Manitoba, 22% of 59 fields had group 1-HR green foxtail. Group 2-HR biotypes of kochia were documented in Saskatchewan, common chickweed and spiny sowthistle in Alberta, and green foxtail and redroot pigweed in Manitoba. Across the Prairies, HR weeds are estimated to occur in fields covering an area of nearly 5 million ha. Of 1,067 wild oat seed samples submitted by growers and industry for testing between 1996 and 2006, 725 were group 1 HR, 34 group 2 HR, and 55 groups 1 and 2 HR. Of 80 submitted green foxtail samples, 26 were confirmed group 1 HR; most populations originated from southern Manitoba where the weed is most abundant. Similar to the field surveys, various group 2-HR biotypes were confirmed among submitted samples: kochia, wild mustard, field pennycress, Galium spp., common chickweed, and common hempnettle. Information from grower questionnaires indicates patterns of herbicide usage are related to location, changing with cropping system. Two herbicide modes of action most prone to select resistance, groups 1 and 2, continue to be widely and repeatedly used. There is little evidence that growers are aware of the level of resistance within their fields, but a majority have adopted herbicide rotations to proactively or reactively manage HR weeds.
  • Authors:
    • Blackshaw, R. E.
  • Source: Crop Protection
  • Volume: 27
  • Issue: 2
  • Year: 2008
  • Summary: Cover crops may have a valuable role to play in developing improved dry bean production systems. A field experiment was conducted to determine the agronomic benefits of including various fall-seeded and spring-seeded cereal cover crops with and without in-crop herbicides in dry bean. Main plot treatments included fall-seeded winter rye, barley, oat, and spring rye; spring-seeded barley, oat, and spring rye; and a no-cover crop control. Subplot treatments consisted of in-crop sethoxydim/bentazon and an untreated control. Fall-seeded cover crops were often superior to spring-seeded cover crops in terms of providing sufficient ground cover to reduce the risk of soil erosion and reducing weed emergence and growth. Among the fall-seeded cover crops, winter rye provided the greatest ground cover and often resulted in the greatest weed suppression. Dry bean density was not affected by any of the cover crops, but fall-seeded cover crops delayed emergence by up to 5 days and delayed maturity by up to 4 days. Cover crop effects on dry bean yield were most evident in the absence of in-crop herbicides, where fall-seeded cover crops increased dry bean yield by 20-90%. Cover crops also increased dry bean yield in 2 of 3 years when in-crop herbicides were used but yield increases were much smaller, ranging from 5% to 13%. These yield increases occurred with fall-seed cover crops that aided in weed management but also with spring-seeded cover crops where weed suppression was not evident, suggesting that cover crops provided additional benefits beyond weed management. Information gained in this study will be utilized to advise farmers on the most suitable use of cover crops in sustainable dry bean production systems.
  • Authors:
    • Bellinder, R. R.
    • Brainard, D. C.
    • Hahn, R. R.
    • Shah, D. A.
  • Source: WEED SCIENCE
  • Volume: 56
  • Issue: 3
  • Year: 2008
  • Summary: Three major hypotheses were examined in this study: (1) the density of summer annual weeds is reduced in crop rotation systems that include winter wheat compared to those with strictly summer annual crops, (2) the integration of a red clover in cropping systems reduces weed seedbank densities, and (3) changes in weed seedbanks due to crop rotation system have greater impact on future crops that are managed with cultivation alone, compared to those managed with herbicides. To test these hypotheses, five 3-year rotation sequences were examined in central New York state, USA: continuous field maize (FC); field maize with red clover (FC+CL); field maize-oats-wheat (FC/O/W); sweetcorn-peas-wheat (SC/P/W), and SC/P/W with red clover (SC/P/W+CL). In the fourth year, sweetcorn, snap beans, and cabbage were planted in subplots with three levels of weed management as sub-subplots: cultivation alone, reduced-rate herbicides (1/2*), and full-rate herbicides (1*). The trial was carried out in two separate cycles, from 1997 to 2000 (cycle 1) and from 1998 to 2001 (cycle 2). Crop rotations with strictly summer annual crops (FC) did not result in consistently higher weed seedbank densities of summer annual weeds compared to rotations involving winter wheat (FC/O/W; SC/P/W; SC/P/W+CL). Integration of red clover in continuous field maize resulted in higher weed seedbanks (cycle 1) or emergence (cycle 2) of several summer annual weeds compared to field maize alone. In contrast, integration of red clover in the SC/P/W rotation led to a 96% reduction in seedbank density of winter annuals in cycle 1, although this effect was not detected in cycle 2. Observed changes in weed seedbank density and emergence due to crop rotation resulted in increased weed biomass in the final year in only one case (sweetcorn, cycle 2), and did not result in detectable differences in crop yields. In contrast, final year weed management had a strong effect on weed biomass and yield; cultivation alone resulted in yield losses for sweetcorn (32 to 34%) and cabbage (0 to 7%), but not snap beans compared to either 1/2* or 1* herbicides.
  • Authors:
    • Butkuviene, E.
  • Source: Biodiversity and animal feed: future challenges for grassland production. Proceedings of the 22nd General Meeting of the European Grassland Federation, Uppsala, Sweden, 9-12 June 2008
  • Year: 2008
  • Summary: Pasture sward improvement investigations were conducted during the period 1980-2003 at the Vezaiciai Branch of the Lithuanian Institute of Agriculture. The focus was on the effects of pasture turf cultivation and resowing time, different cover and catch crops, and herbicide use in combination with pasture resowing. Cover crops, catch crops and pasture resowing time all affected dry matter (DM) yield. The most suitable time for turf cultivation was August-September and spring was most suitable for grass sowing. The best cover crops were barley for grain and oat-vetch mixture for green forage/silage. Potato and cereals were the best catch crops for pasture resowing. DM yield of resown pasture increased by 0.04-2.181 ha -1 compared with old untreated pasture. Resowing led to increased proportions of legumes in the sward by 1.1-9.2%, while the proportions of forbs decreased by 9.1-14.9%.
  • Authors:
    • Nason, R.
    • Entz, M.
    • Froese, J.
    • Ranjan, R.
    • Kahimba, F.
  • Source: Applied Engineering in Agriculture
  • Volume: 24
  • Issue: 3
  • Year: 2008
  • Summary: Excess root zone soil moisture resulting from annual precipitation in excess of crop water requirements negatively affects crop yields. A field study was conducted in the 2005 and 2006 seasons on sandy loam soils to investigate the influence of berseem clover ( Trifolium alexandrium L.) cover crop in oats ( Avena sativa L.) on soil temperature, infiltration, and soil moisture redistribution within the growing season and during the fall to spring seasons. A 4-year crop rotation experiment to investigate farming with fewer chemicals was used to grow oats in a no-till cultivation system with and without the cover crop. The total and unfrozen water contents were measured in the field using neutron moisture meter and time domain reflectometry, respectively, at 0.2-m intervals from the surface to 1.8-m deep, plus a 0.1-m measurement depth. The cover crop significantly reduced soil moisture during the growing season resulting in significantly lower biomass yields (6146 kg ha -1 combined biomass for oats and berseem clover, vs. 7327 kg ha -1 for oats alone). By mid-August 2005, the cover crop treatment had 34.6% lower water content (0.17 vs. 0.26 m 3 m -3) within the 0.0- to 0.7-m root zone depth compared to the non-cover crop. During the fall, the soil profile in the cover crop treatment was 3°C warmer, thus delaying soil freezing and leading to a shallower depth of the frozen soil layer (0.4 vs. 0.6 m) in March 2006. During the spring, the cover crop treatment warmed and thawed earlier enabling more snow melt infiltration and deep percolation. Areas experiencing excess soil moisture could use annual cover crops as a means for reducing excess soil moisture during the summer growing season and avoiding accumulation of soil moisture during the fall, winter and spring seasons.