bluuebunny/crossref_metadata_2025_split huggingface dataset:
Fertilizer requirements for maintenance of a perennial ryegrass (Lolium perenne L.)/white clover (Trifolium repens L.) pasture growing on a humus iron podzol in N.E. Scotland
Authors: RANGELEY ANNE 
Published: April 2006

AbstractRyegrass/white clover pastures were reseeded on heather moor in north‐cast Scotland in 1978/79. By 1981, despite moderate fertilizer applications, the pastures had deteriorated and dry matter (DM) production was low. After preliminary soil and herbage analysis an omission trial was carried out in 1982/83 at two sites (A and B) to identify the factors which limited production.At site A depressions in growth occurred in the absence of N, P and K. Perennial ryegrass was severely N deficient with concentrations in leaves of less than 22 g N kg−1 in spring and summer even after application of 120 kg N ha−1 annually. Rates of nitrogen fixation were high in spring but rapidly declined in June and July as the soil moisture tension increased. Application of N fertilizer also reduced the N2 fixation rate. Deficiencies of F and K occurred despite apparently high levels of extractable F in the soil. Uptake of these nutrients was inhibited in the dry soil during the summer. White clover was more susceptible to drought than perennial ryegrass, probably because it rooted at a shallower depth.Growth at site B was limited by acidity and lack of N and K. The soil pH was 4 8 (s.d. = 0middot;75) at 1‐5 cm depth. Application of 2 5 t lime ha−1 in spring 1982 had not altered the pH by autumn 1983.It was concluded that methods of incorporating lime into the soil, together with ways of increasing the rates of N2 fixation by white clover and transfer to grass, should be investigated further. Regular small applications of N and K may be necessary to sustain DM production at the level required by the farming system.
Effects of sowing date, placement of seed, vegetation suppression, slugs, and insects upon establishment of no‐till alfalfa in orchardgrass sod†
Authors: BYERS R. A. , TEMPLETON W. C. 
Published: April 2006

AbstractFour treatments designed to affect some environmental factors during germination and establishment of alfalfa were: two sowing dates (March and May) to produce differences in temperature, light and soil moisture; two sowing methods (notill drill and hand sowing) for creating different degrees of soil‐seed contact; mowing and banded and broadcast sprays of glyphosate to produce varying degrees of plant competition; and methiocarb bait combined with carbofuran granules vs. no pesticide to establish different levels of invertebrate feeding.Alfalfa dry matter (DM) production was affected very little by sowing date in two identical experiments. It was unaffacted by sowing method in experiment 1 (1983) but was significantly higher when alfalfa was sown with a drill in the second trial (1984). Highest alfalfa DM yields were achieved when competition was suppressed by broadcast spraying rather than bands, but details of effect differed in the two experiments.Pesticide treatments yielded more alfalfa DM in the year of establishment. Slugs, Deroceras leave (Müller) and D. reticulatum (Müller), and the potato leafhopper, Empoasca fabae (Harris), were among the potential pest species controlled and may have been partly responsible for the observed effects.
Sward maintenance of Lolium multiflorum by slurry seeding
Authors: JONES E. L. , ROBERTS J. E. 
Published: April 2006

AbstractA field investigation into the effect of slurry seeding on the dry‐matter yield and persistence of an Italian ryegrass sward was assessed over a 3‐year period (1984–86) under a regime of three cuts per season combined with sheep grazing in early spring and late autumn. Results showed that slurry plus seed treatments produced up to 30% more herbage dry matter and a significantly higher tiller density than where no slurry or seed were used. Slurry application with and without seed also reduced the proportion of weed grasses (mainly Poa spp.) in the sward. It is concluded that slurry seeding is a useful technique for extending the productive life of an Italian ryegrass sward.
Nitrogen concentrations in the cell wall and lignocellulose of smooth homegrass herbage*
Authors: SANDERSON M. A. , WEDIN W. F. 
Published: April 2006

AbstractApplying nitrogen (N) fertilizer to grass generally increases N concentration in herbage. Not as well documented, however, are N fertilizer effects on concentrations of N in plant cell walls and lignocellulose. The objective four study was to ascertain how N fertilizer applied with or without a nitrification inhibitor would affect N concentrations in the cell wall (neutral‐detergent fibre (NDF)) and lignocellulose (acid‐detergent fibre (ADF)) of smooth bromegrass (Bromus inermis Leyss). Nitrogen fertilizer ((NH4)2SO4) was applied at 0, 125, or 230 kg N ha−1 in combination with 0, 2–5, or 50 kg ha−1 of nitrapyrin (2‐ chloro‐6‐(trichloromethyl) pyridine) to smooth bromegrass in April of 1985 and 1986. Herbage was harvested at 2, 4, 6 and 8 weeks after treatment. Freeze‐dried herbage samples were analysed for in vitro digestible dry matter (IVDDM), total N, and N in neutral‐ and acid‐detergent fibre (NDFN and ADFN, expressed as g kg−1 NDF and ADF, respectively). Nitrapyrin had no effect on IVDDM, total N, NDFN or ADFN, Nitrogen fertilizer increased concentrations of total N in herbage dry matter, and increased N concentrations in NDF and ADF. Most of the increase in total N concentration occurred in the neutral‐detergent soluble portion. When NDFN and ADFN concentrations were expressed on a total N basis (g k g−1 of total N), N fertilizer had no effect. Available fibre N (AFN; calculated as NDFN minus ADFN, each expressed as g kg−1 total N) was not affected by N fertilizer. The average AFN concentration was 93 g kg−1 total N. Nitrogen fertilizer did not affect herbage quality; however, age of herbage had marked effects on herbage quality.
The performance of high‐latitude grass varieties under Scottish conditions: seasonal distribution of dry‐matter production
Authors: HAY R. K. M. 
Published: April 2006

AbstractThe seasonal patterns of dry‐matter (DM) production by swards of Norwegian grasses originating from high latitudes >61°N (Dactylis glomerata Hattfjelldal, Phleum pratense Engmo and Poa pratensis Leikra) were compared over 2 years (1986 and 1987) with those of grasses developed at lower latitudes, 52°N (Dactylis glomerata Cambria, Phleum pratense Motim and Lolium perenne Perma) at a lowland site in southwest Scotland (55.5°N, altitude 45 m). In each year, there was a significant enhancement of the DM production of the high‐latitude varieties of Dactylis glomerata, Phleum pratense and Poa pratensis at harvests during May and June, although the lower latitude grasses gave a higher proportion of annual production than the Norwegian grasses in April and from September onwards. These findings are compatible with the observed stimulation of DM production of high‐latitude grasses by daylength extension under controlled conditions. However, since the stimulation of DM production did not occur until the normal peak of production in May and June, it served to accentuate the skewed distribution of production in Scotland, rather than to improve production earlier in the season. Since the total annual DM production was significantly lower for the high‐latitude grasses in general at the lowland site, there does not appear to be a clear role for these grasses in UK agriculture.
Assessment of contrasting perennial ryegrasses, with and without white clover, under continuous sheep stocking in the uplands
Authors: DAVIES D. A. , FOTHERGILL M. , JONES D. 
Published: April 2006

AbstractPotential lamb production from grass‐clover (75–80 kg N ha−1) swards was compared with that from grass‐only (160–200 kg N ha−1) swards from 1985 to 1987 at the Bronydd Mawr Research Centre in mid‐Wales. Separate pastures of three perennial ryegrass (Lolium perenne L.) varieties; Aurora (very early‐flowering diploid), Meltra (late‐flowering tetraploid) and Aberystwyth S23 (late‐flowering diploid), with and without Aberystwyth S184 small‐leaved white clover (Trifolium repens L.), were continuously stocked with Beulah Speckled Face ewes and their Suffolk cross lambs from spring (late April) until weaning in mid‐July. From late July the pastures were grazed with weaned lambs until early November.Individual lamb liveweight gain was 8% more (P < 0·001) pre‐weaning on grass‐clover than on grass‐only swards and 30% more (p < 0·001) post‐weaning. Averaged over three years, mean stocking rate was 17% higher (p < 0·001) pre‐weaning and 29% higher (p < 0·001) post‐weaning on the grass‐only pastures. Even so, total lamb output (kg ha−1) was similar from the two sward types, although during the pre‐weaning period lamb production was 9% higher (P < 0·05) from grass‐only swards.The results show the potential of grass‐clover (low N) swards to improve the efficiency of lamb production from grassland since better individual lamb growth rate compensated for the lower stock‐carrying capacity. That is, similar output was achieved with lower cost of fertilizer N input and with the lower costs associated with carrying fewer animals.
Slot‐seeding investigations 7. The effects of two grasssuppressants on the growth of white clover introduced into permanent pasture
Authors: STANDELL CHRISTINE J. 
Published: April 2006

AbstractThe benefits of reducing competition from the surrounding grass sward against slot‐seeded clover were measured in terms of white clover dry matter production following applications of two grass‐suppressing herbicides, propyzamide and carbetamide.Clover was slot‐seeded in early June 1983 and herbicides were applied in September and October 1983. The later application was more damaging to the surrounding sward. Generally, the September spraying was more effective in encouraging white clover, especially from July of the following year. Only by September 1984 did the October applications result in higher clover yields than the September applications.Propyzamide had the greater stimulatory effect on white clover production but it also damaged the grass more than carbetamide. Increasing the dose of each herbicide increased grass damage. However, with treatments applied in September, the loss was more than compensated for by an increase in clover and in total dry matter production at the end of the year.The results suggest that either of these herbicides, but especially propyzamide, can be used to increase both total dry matter production from the sward and the contribution from slot‐seeded white clover.
Comparison of the fermentation quality and nutritive value of sulphuric and formic acid‐treated silages fed to beef cattle
Authors: KENNEDY S. J. 
Published: April 2006

AbstractFive experiments were carried out in the years 1980‐1983 and 1986 to study the effect of treating grass at ensiling with sulphuric acid (850 g kg−1) and formic acid (850 g kg−1) additives alone, and in mixtures with or without formalin on the preservation of grass, in vivo digestibility in sheep, in‐silo loss, intake and performance of finishing cattle.Primary growth grass was ensiled in experiments 1 (3–4 June 1980), 2 (12‐15 June 1981) and 3 (31 May‐2 June 1982), primary regrowth grass in experiment 4 (1‐2 August 1983) and secondary regrowth grass in experiment 5 (7‐10 October 1986). During the ensiling period within each experiment, approximately 60 t of unwilted, double‐chopped, additive‐treated or untreated grass was packed into covered concrete‐walled 60‐t capacity silos. The dry matter (DM) contents of the ensiled grass in experiments 1, 2 and 5 ranged from 155‐180 g kg−1 and were lower than those recorded in experiments 3 and 4 (214 g kg−1). With the exception of grass ensiled in experiment 2, where water‐soluble carbohydrate (WSC) contents were low, at 104 g kg−1 DM, grass in all other experiments contained relatively high WSC contents ranging from 140‐154 g kg−1 DM.In experiments 1, 3 and 4 all silages were well‐preserved. However, in experiment 2 the 450 g kg−1 sulphuric acid‐treated and formic acid‐treated silages displayed significantly lower pH, buffering capacity (Bc) and ammonia nitrogen contents than the untreated silage. In experiment 5, the sulphuric acid‐treated and formic acid‐treated silages displayed significantly lower pH, Bc, ammonia nitrogen, butyrate and volatile fatty acid (VFA) contents than the untreated silage.Each of the silages was offered daily with various levels of a supplementary concentrate for approximately 70‐d periods to twelve animals of mixed breed in experiments 1, 3, 4 and 5 and to fifteen animals in experiment 2. All animals weighed between 380‐470 kg at the start of the experiments.In experiments 1, 2 and 3 there were no significant differences between silages for any of the intake or animal performance parameters. In experiment 4, cattle fed the formic acid‐treated silage displayed significantly higher silage DM intakes and daily liveweight gains than those fed the sulphuric acid‐treated and untreated silages; in experiment 5, cattle fed the formic acid‐treated silage displayed significantly higher silage DM intakes than those fed the untreated silage. It was concluded that formic acid was a more effective silage additive than sulphuric acid.Increasing the level of supplementation significantly decreased silage DM intakes in cattle in experiments 3 and 4, and significantly increased daily liveweight gains and daily carcass in cattle in experiments 1, 3 and 4.
Sward canopy structure and the bite dimensions and bite weight of grazing sheep
Authors: BURLISON A. J. , HODGSON J. , ILLIUS A. W. 
Published: April 2006

AbstractSeventeen grass or oats swards, displaying a wide and largely independent variation in surface height and bulk density, were produced using different seed rates at sowing and different cutting or grazing pre‐treatments. Four sheep confined in cages were allowed to take twenty bites from small patches of each sward, and measurements of bite weight and the physical dimensions of the average bite in the sward (bite depth, area and volume) were related to a range of sward structural characteristics.Mean bite weight per sward ranged from 40 to 330 mg dry matter (DM). It was positively related to surface height (range 6–55 cm), which acted primarily upon bite depth and hence bite volume, and to the bulk density of the grazed stratum (range 0·1–2·0 mg DM cm −3) which influenced bite weight directly. The effects of surface height and grazed stratum bulk density were independent and additive, resulting in a planar response surface.The influence of sward variables on bite area was less clear than on bite depth, but within a given grass species the effect of surface height appeared to be positive and that of the population density of grazed leaves and stems negative. These findings are considered in relation to a theory concerning grazing mechanics.The merits of the grazing cage technique are discussed and suggestions made for further work.
Assessment of contrasting perennial ryegrasses, with and without white clover, under continuous sheep stocking in the uplands. 3. Herbage production, quality and intake
Authors: DAVIES D. A. , FOTHERGILL M. , JONES D. 
Published: April 2006

AbstractHerbage characteristics were monitored over 3 years (1985–1987) in three perennial ryegrass (Lolium perenne L.) varieties as grass/only (200 kg N ha−1) and grass/clover (Trifolium repens L.) (75 kg N ha−1) swards when continuously stocked with sheep. Although mean total annual herbage production was similar from the grass varieties, growth of Aurora, a very early‐flowering variety, was higher than that of Aberystwyth S23 and Meltra (tetraploid) late‐flowering types in spring. Herbage production from grass‐only swards was 15% higher than from grass/clover swards. In vitro organic matter digestibility (OMD) of Aurora and Meltra was 34 g kg −1 and 26 g kg −1 higher (P < 0·01) than that of S23. Averaged over varieties, the OMD of grass/clover was 25 g kg −1 higher (P < 0·05) than grass‐only during the post‐weaning period. Individual lamb digestible organic matter intake (DOMI) was 22% higher (P < 0·05) on grass/clover than on grass‐only during this period. Water‐soluble carbohydrates content of Aurora was 42% higher (P < 0·001) than that of both Meltra and S23.Herbage characteristics were related to lamb performance reported previously. Lamb production was positively correlated with DOMI. However, the magnitude of differences in lamb performance between treatments was much greater than the extent of differences detected in herbage characteristics.
The effect of rate and timing of phosphate fertilizer on the yield and phosphate off take of grass grown for silage at moderate to high levels of soil phosphorus
Authors: PAYNTER R. M. , DAMPNEY P. M. R. 
Published: April 2006

AbstractA series of twenty‐one trials was undertaken during 1985–1988 to investigate the effect on lowland silage crops of 0, 40 or 80 kg ha−1 phosphate (P2O5) fertilizer applied as triple superphosphate (46% P2O5) in the autumn, spring or as a split application (spring and after first cut). All sites had moderate to high sodium bicarbonate‐extractable soil phosphorus contents (18–34 mg P 1−1 in air‐dried soil).Significant yield responses were obtained at eight of the forty‐two individual cuts (two cuts per site). When meaned over all sites, spring or autumn applied phosphate increased dry matter yield at both first and second cut (mean total increase 0·32 t ha−1), though the effect was significant only at the highest phosphate rate. The time of phosphate application had no overall effect on yield. Herbage P concentration and phosphate off take were significantly increased at both cuts by both rates of phosphate. Generally, the most recent application had a significantly greater effect than other timings. These findings indicate that DM yield responses to freshly available phosphate can occur on soils of moderate P status.
Supplementary forage for grazing sheep. 2. Effects on weaned lambs
Authors: MARTIN J. H. , PHILLIPS C. J. C. , ALCOCK M. B. 
Published: April 2006

AbstractIn two experiments weaned entire ram lambs were offered either pasture alone or pasture plus ad libitum conserved forage for 7–12 weeks during the finishing period. Herbage height was maintained at 3·2 cm on both treatments by manipulation of stocking rate in the twenty‐four plots (twelve per treatment) used for the experiment. In experiment 1 silage, which was of lower metabolizable energy (ME) and crude protein (CP) content than the grazed herbage, was consumed at an average of 194 g DM head−1 d−1, providing approximately 40% of total DM intake requirements. In experiment 2 a strawmix, containing (g k g −1 freshweight) 450 g barley straw, 300 g concentrate and 250 g molasses and again with a lower ME and CP content than the grazed herbage, was consumed at an average of 57 g DM head−1 d−1, providing approximately 11% of total DM intake requirements. In both experiments stocking rate was increased by 20–25% by providing forage, but lamb growth rate was not affected.
Differences in lamina wettability in some permanent pasture grass species and two Lolium perenne cultivars
Authors: TALLOWIN J. R. B. , TYSON C. M. , BROOKMAN S. K. E. 
Published: April 2006

AbstractLamina wettability, assessed using water droplet contact‐angle and surface water‐retention measurements on excised leaves, was examined in Lolium perenne cv. Melle, cv. Condesa and an indigenous population from an old pasture, Holcus lanatus, Poa trivialis and Agrostis stolonifera. The species fell into two significantly distinct categories, those with unwettable laminae, namely H. lanatus and A. stolonifera, and those with highly wettable laminae, P. trivialis and the three L. perenne populations. There was no significant difference between the L. perenne populations, which had the most wettable laminae overall. The possible implication of these differences in lamina wettability on animal production is discussed.
Wheel‐induced soil compaction effects on ryegrass production and nitrogen uptake
Authors: DOUGLAS J. T. , CRAWFORD C. E. 
Published: April 2006

AbstractSoil and crop responses to zero, small and large tyre/soil contact stresses applied by tractors were studied on a newly reseeded ryegrass sward during 1987 and 1988. The compactive efforts, applied during winter or at the time of spring fertilizer application or at first harvest, were sufficient to increase significantly bulk density in the topsoil layer compared with that in a zero traffic control treatment. The largest increases in soil bulk density occurred after spring‐time traffic in the first year (1987) of the experiment. In both years, the resulting soil conditions after heavy compaction were relatively unconducive to primary grass growth and first cut yields; the soil was wetter (less well aerated), of greater strength and colder in the early spring, and warmer in the late spring than the soil in the zero and more lightly compacted treatments. During a relatively wet summer (1987) there were significant benefits to second and third cut yields from minimizing compaction; in the relatively dry summer of 1988 there were no compaction effects at second cut. In both years, impaired uptake of nitrogen was related closely to increased amount of traffic and soil density.
Degradation of nitrogenous compounds in conserved forages in the rumen of dairy cows
Authors: TAMMINGA S. , KETELAAR R. , van VUUREN A. M. 
Published: April 2006

AbstractDegradation in the rumen of dairy cows of nitrogenous compounds in 35 grass silages and 12 grass hays was studied by means of the nylon bag incubation technique. Silages varied in dry matter content, crude protein content and date of harvesting; hays varied mainly in crude protein content. Measurements in both forages were washable (W), degradable (D) and undegradable fraction (U) and rate of degradation (ks) of D. W and U were measured as the residue after washing without incubating (W) or after 336 h in the rumen (U). N escape (E) was calculated from these data, assuming a ruminal passage rate of 4·5% per hour.E (N escape from the rumen) in hays was substantially higher than in silages, mainly because a large proportion of N compounds in silage became soluble during the ensiling process. Of the total variation in E, around 80% could be explained in both forages. In silage, E was positively influenced by dry matter content, negatively by crude protein content and positively by the number of days elapsed since 1 April. This effect of day of harvesting was mainly through an increase of U and may not be beneficial to the animal. In hays crude protein content was the major factor explaining variation in E.
Barley/pea mixtures as cover crops for grass re‐seeds
Authors: GILLILAND T. J. , JOHNSTON J. 
Published: April 2006

AbstractSubstantial annual fluctuations in the performance of arable silage mixtures, comprising Minerva forage pea and Goldmarker barley, were observed from ten annual sowings between 1977 and 1986, Total dry matter (DM) yield varied between 2·5 and 11·5 t ha−1. Dry matter content also ranged widely from 10·3% to 20·0% and there was a large variation in the proportion of peas in the DM (0·44 to 0·90). Almost 80% of this yield variation was due to the fluctuation in pea performance and over 60% of all yield variation was related to the variation in sunshine hours and air temperature.In 1983 and 1984 differences in seed rate of between 20 and 140 kg ha−1 of Minerva and 80 and 160 kg ha−1 of Goldmarker influenced the forage composition at harvest, with the pea component capable of outgrowing and suppressing the other species when sown at over 80 kg ha−1. Very high yields of peas were associated with increasing stress on the undersown grass re‐seed and were considered undesirable.It was concluded that sowing rates of between 120 and 160 kg ha−1 for barley and a maximum of 60 kg ha−1 for peas would, in most years, provide the best compromise between attaining good arable silage yields and avoiding excessive dangers of damage of undersown grass re‐seeds.