ALBERT

Notizen: Experiments were carried out on seven sites in Fermanagh to investigate the yield loss caused by leatherjackets in grassland. Populations on the sites ranged from 65,000 to 865,000 ha−1 and significant damage was recorded from all sites except the least populated. Greater yield increases were obtained by controlling leatherjackets in September when compared with control in March. Regression models were fitted and it was found that 125,000 leatherjackets ha−1 in March caused a yield loss of 50 kg herbage dry matter (DM) ha−1 by mid-May. Based on these figures the average yield loss to leatherjackets in Northern Ireland, from 1965 to 1982, was 208 kg DM ha−1. Controlling leatherjackets in September, rather than March, increased the potential avoidable yield loss by a factor of 2.72. The average yield loss at first silage cut is therefore 566 kg DM ha−1. On average, 100,000 ha grassland in Northern Ireland may be suffering an annual loss of 1t herbage DM ha−1.

Notizen: The utilization of sown and indigenous plant species was studied in three experiments in which plots were stocked with similar live weights of sheep and goats. In the first experiment the animals grazed plots containing 0–5 ha of rush (Juncus effusus)- infested reseeded pasture and 0–5 ha of unimproved blanket bog. The second and third experiments took place on old rush-infested improved pasture; in one experiment two levels of herbage mass of grass were provided while in the other the rushes were cut in spring or remained uncut.The goats grazed the rushes readily in all three experiments. Reduction in herbage mass of grass increased utilization of rushes by goats although these animals still grazed rushes when grass supply was plentiful. Sheep scarcely grazed J. effusus even when hard-pressed by shortage of grass. Both sheep and goats grazed J. acutiflorus.In Experiment I sheep utilized reseeded pasture more heavily than did goats. Sheep grazed similar proportions of the leaves of grass and clover while goats grazed a lower proportion of clover leaves as compared with grass. Among the grasses sheep discriminated in favour of Lolium perenne whereas goats did not. On the blanket bog vegetation, Eriophorum vaginatum and Calluna vulgaris were grazed both earlier in the season and more heavily by goats than by sheep.The relationships between sward structure and grazing height in accounting for differences in species selection by sheep and goats are briefly discussed. The possibility of using goals to control coarse weeds in hill pasture and for strategic grazing to manipulate floristic composition is outlined.

Notizen: The performances of a rising-plate meter and a single-probe electronic capacitance meter were compared for estimating the herbage mass of irrigated pastures both before and after grazing by dairy cows. Mean CV for the rising plate meter and the single-probe meter were 12.7% and 13.3% respectively when herbage mass was measured before grazing, and 21.8% and 15.4% respectively immediately after grazing. These coefficients of variation indicate that while the performance of the two meters was similar when herbage mass was measured before grazing, the single-probe meter was a more precise instrument for estimating herbage mass after grazing.Trampling of herbage prior to measurement had a major effect on the regressions of both meters; the regression intercept was increased by 2800 kg dry matter (DM) ha−1 for the rising-plate meter and by 2580 kg DM ha−1 for the single-probe meter. The slopes of the graphs, however, remained unchanged.It was concluded that while the single-probe meter performed better than the rising-plate meter for estimating the mass of post-grazing herbage when trampling was negligible, the large effect that trampling had on the post-grazing calibration regressions precluded both instruments from general use in dairy cattle research. This indicates that another technique is required in circumstances in which pastures are heavily trampled.

Notizen: Only a very limited number of species, including red fescue (Festuca rubra), perennial ryegrass (Lolium perenne), timothy (Phleum protense) and white clover (Trifolium repens) are considered as suitable for wet hill land. Detailed comparison of red fescue, perennial ryegrass and timothy on contrasting acid brown earth and stagnogley soils from 1966 to 1969 at Pant-y-dŵr Hill Centre (305 m OD) highlighted the advantages of red fescue in annual DM production and its more even distribution over a longer growing season but also indicated drawbacks of slow initial establishment and lower feed quality. In vitro DOMD of red fescue averaged 645 g kg−1 over the year compared with 690 g kg−1 for perennial ryegrass and timothy. Assessment of a narrow range of species under surface seeding conditions on a stagnogley soil from 1971 to 1975 confirmed the value of red fescue in DM production and persistence. The results are discussed in relation to the characteristics required in herbage species for hill land improvement.

Notizen: High-yielding grass-legume mixtures play an important role in forage-animal systems but finding compatible and adapted species can sometimes be difficult. The objective of this study was to examine productivity of perennial ryegrass and orchardgrass in pure stands with N and in mixtures with legumes.Broadcast sowings were made on conventionally prepared seedbeds in August 1979 and May 1980 on a Hagerstown silt loam soil (fine, mixed mesic Typic Hapludalf). When sown alone orchardgrass cv. Pennlate and perennial ryegrass cv. Reveille received rates of N ranging from 0 to 448 kg ha−1 a−1. The grasses were also grown in mixtures with alfalfa cv. Arc, red clover cv. Arlington, or birds foot trefoil cv. Viking. The same legumes were sown alone. Four legume seed rates were used in both the pure legume and mixed stands.Orchardgrass-N swards were more productive than ryegrass-N swards over 3 years. More dry matter (DM) was harvested from pure stands of

Notizen: Fungicide applied to plots of perennial ryegrass cv. S24 in the autumn of 1981 significantly increased tiller number and total dry matter accumulation in February and March of 1982. However, fungicide application in the autumn of 1982 failed to increase tiller number or dry matter accumulation in the spring of 1983. It is suggested that fungicide application in autumn 1981 prevented the death of tillers caused by fungal attack after snow covered the plots in December 1981.

Notizen: A mathematical model of grass production and utilization on a dairy farm is described. Using the model an assessment has been made of the extent to which financial uncertainty arising from year-to-year variability in grass yields, coupled with a preference among farmers for minimizing risks, may explain the relatively low stocking rates and observed nitrogen usages on many dairy farms in England and Wales. The degree of risk has been equated with the probability of profits in a particular year being less than those required to cover the consumption needs and short-term borrowing requirements of the farmer. The results of the analysis indicate that a strategy of minimizing risks may lead to a significantly lower stocking rate than one of maximizing profits. Thus, considerations of risk may lead to stocking rates which are suboptimal from the viewpoint of economic and biological efficiency. However, there is no evidence to suggest that the comparatively low average usage of nitrogen on dairy farms in the UK is determined by risk considerations. On the contrary, increasing nitrogen usage lowers the apparent financial risk at a given stocking rate.

Notizen: The herbage dry matter (DM) harvested, N response and herbage quality of monocultures and mixtures of Holcus lanatus (local ecotype) and Lolium perenne (cv. S24) were compared in a field experiment. The species were seeded in the proportions 100:0, 75:25, 50:50, 25:75 and 0: 100; three rates of N were applied (150, 300 and 450 kg ha−1) and five or six cuts were taken in each of four harvest years. H. lanatus established poorly in the seeding year and in the first full harvest year L. perenne contributed 1, 54, 76, 89 and 99% of the total herbage DM harvested from the five sward types (mean of N treatments). Only a small decline in the L. perenne content of the swards occurred during the experiment.Total amounts of herbage harvested were significantly lower for H. lanatus monoculture than for the other sward types in three of the four harvest years However, L perenne monoculture yielded significantly more total DM than mixtures with H lanatus in only one of the four harvest years. The five sward types did not differ overall in response to N fertilization. Nitrogen, phosphate and potassium content of the herbage was greatest for H. lanatus monoculture and decreased with increasing proportions ofL perenne present in the mixtures.Thus the presence of a high proportion of H. lanatus in mixture with L. perenne cv. S24 had

Notizen: Two experimental populations of Italian ryegrass selected for high and low magnesium content were established as swards, harvested fresh daily and offered to sheep. Chemical analysis of the crops showed a 44% higher Mg and a 22% higher Ca concentration in the high-Mg selection but no significant differences between the selections for the other minerals.Blood and rumen contents were sampled throughout the feeding period and voluntary intake, digestibility and mineral balances for Na, K, Mg, Ca and P were determined. Magnesium intake, apparent availability and retention were significantly greater with the high-Mg selection. There were no significant differences in the plasma-mineral concentrations and all were within the normal range. Rumen fluid from animals fed the high-Mg selection had a higher proportion of soluble Mg and a higher Na:K ratio in the supernatant liquor.

Notizen: A perennial ryegrass sward was managed by continuous stocking with sheep (April–September) for 4 successive years after sowing. The sward was grazed to maintain a leaf (lamina) area index (LAI) close to 1.0. Areas of the sward were released from grazing on three occasions: once during summer in the third year after sowing, and twice during spring and summer in the fourth year after sowing. There were marked changes in the structure and physiology of the continuously stocked sward following release from grazing. After several successive years of continuous stocking, the sward comprised a large population of small tillers and the small LAI resulted in consistently low rates of photosynthesis. Following release from grazing, photosynthesis increased markedly as the LAI increased but this change was associated with the loss of a large proportion of the population of tillers. There were seasonal differences in the pattern of changes in photosynthesis and tiller numbers following release from grazing which were not apparent under continuous stocking. The changes in the structure and physiology of the sward following release from grazing suggest that the net accumulation of herbage in areas of sward from which the animals are excluded, for instance using cages, may be an unreliable estimate of production under continuous stocking.

Notizen: A randomized block experiment was conducted to compare unwilted and wilted grass silages and the effects of the feed additive monensin sodium on the silage intake and performance of finishing beef cattle. Two regrowths from a predominantly perennial ryegrass (cv. S24) sward were ensiled either without wilting or after field wilting for 3 d (dry matter (DM) concentrations 161 and 266 g kg−1 respectively). Both silages were treated with formic acid (2·6 and 30 litre t−1 respectively) and were well preserved. The silages were offered ad libitum to forty-eight Charolais-cross cattle (thirty-two steers and sixteen heifers, mean initial live weight 351 kg) for 145 d. All animals received 2·2 kg concentrates per head daily and half of those on each silage treatment received in addition 200 mg monensin sodium per head daily. Silage DM intake was 5.04, 504. 5·48, 5·63 ± 0.134 kg d−l; fasted liveweight gain was 0·69, 0·77. 0·64 and 0·73 ± 0.033 kg d−l and carcass gain was 0·47, 0·50, 0·40 and 0·45 ± 0·020 kg d−1 for the unwilted silage without and with monensin and the wilted silage without and with monensin respectively. It is concluded that wilting grass of low DM concentration for 3 d prior to ensiling reduced the performance of finishing beef cattle below that obtained from well-preserved unwilted silage in spite of a higher DM intake being achieved with the wilted silage. The inclusion of monensin sodium in a silage-based diet increased performance without significantly affecting feed intake.

Notizen: Formic acid, sodium diacetate, propionic acid and two of its ammonium salts, ammonium isobutyrate and tributyl phosphate, were examined for their antimicrobial effects with cultures of micro-organisms typical of the microflora of moist hay. The assays, which were conducted at pH 5, 6, 7 and 8, revealed that all potential preservatives discriminated against actinomycetes in particular and were least effective against fungi. In addition, it was apparent that antimicrobial properties were enhanced under slightly acid conditions and for this reason the use of mixtures of organic acids and salts in commercial hay preservatives is justified. Tributyl phosphate not only had the strongest antimicrobial properties of the compounds tested but was also the least affected by pH.

Notizen: Yields of grass were measured on three dairy farms in 1981. Farm 1, on free-draining loamy soil over chalk, produced 10.3 t DM ha−1 using 336 kg N ha−1. Farm 2, on poorly-drained loam over Oxford clay, produced 12.8 t DM ha−1 using 354 kg N ha−1. Farm 3, on loam over clay with some free-draining sandy loam, produced 9.5 t DM ha−1 with 169 kg N ha−1. Allowing for differences in soil nitrogen and summer rainfall these yields were quite close to expectations from experimental results, despite considerable poaching damage to some swards.Animal production records were kept and all livestock were weighed every 6 months, so as to calculate the utilized metabolizable energy (UME) output from grassland on each farm. These were 73, 62 and 59 GJ ha−1 on farms 1, 2 and 3 respectively.The UME output, expressed as a proportion of the yield of grass (converted to ME), was taken as the ‘efficiency of utilization’ of grass. This was 70% on farm 1,44% on farm 2 and 58% on farm 3. Results are presented separately for the summer and winter 6 months. Utilization by grazing appeared to be markedly reduced under very wet soil conditions. Major losses occurred in the conservation of grass.The results begin to establish a valuable base of data from commercial farms.

Notizen: The establishment and growth of white clover (cv. Grasslands Huia) was investigated in two experiments with seeds sown in slots cut in old permanent pasture in early May 1982. In the first experiment, fully protected from pests and diseases, either 50 (low), 100 (medium) or 200 (high) seeds were sown evenly per metre length of slot; 100 seeds were also sown in a clumped pattern unevenly. In the second experiment, the effects of various combinations of molluscicide, insecticide and fungicide were investigated.Nine weeks after sowing there were 27, 37, 34 and 62 seedlings m−1 on the low, medium even, medium uneven and high seed-rate treatments, representing percentage establishments of 54, 37, 34 and 31 respectively. By September, however, there were no significant differences between the dry weights m−l of any of the treatments. In the second experiment, damage by slugs occurred early in treatments without molluscicide and caused a mean reduction of 70% in seedling establishment. As a result significantly smaller dry weights m−1 of clover were recorded in September in these than in other treatments. Failure to protect against insects resulted in smaller seedlings.The results indicated that variations in seed rate within the range investigated were not critical but that failure to protect against pests decreased percentage establishment and subsequent growth.

Notizen: Masham ewes were stocked at 12(L), 16(M) or 20 (H) ewes ha−1, with 1·8 lambs per ewe on average, on two blocks (A and B) in both 1976 and 1977. Silage was offered at pasture to the ewes in early lactation and as stocking rate increased from 12 to 16 and then 20 ewes ha−1, 47, 73 and 100 kg DM per ewe was consumed respectively. Silage was cut mainly in the autumn and 179, 100 and 9 kg per ewe was made for L, M and H respectively. More variation between treatments was measured in net herbage accumulation in summer than spring and 11·4, 10·0 and 9·7t DM ha −1 was grown over the whole season for L, M and H respectively as a mean of both years.High intakes of herbage OM were measured with values up to 40 g per kg live weight for BL lambs in 1976. Rapid lamb growth was achieved. There were effects of stocking rate on lamb performance and for L, M and H the respective growth rates to 4 weeks were 266, 248 and 247 g d−1; growth rates to sale were 274, 263 and 252 g d−1; days to sale were 124, 126 and 129; mean carcass weights were 17·7, 17·1 and 16·7 kg. Most ewes lost weight in early lactation, especially AH and BH in 1976, but there were no stocking rate effects on ewe weight change in 1977.

Notizen: Measurements of rates of growth and senescence of leaf lamina per tiller and of changes in tiller population densities were made in three experiments designed to investigate the influence of sward slate on leaf turnover and net production under continuous stocking.In each experiment initially uniform swards were fenced to provide four plots on which animal numbers were adjusted twice weekly to give a series of swards maintained as nearly as possible in a steady state with respect to sward surface height (range 1.1–6.4 cm) and herbage mass (range 440–2690 kg OM ha−1). Two experiments were carried out in July–September on vegetative swards and one in May–June on a reproductive sward. Measurements were begun 3–7 weeks after treatments were started and were repeated weekly during 3–4 week measurement periods.In all three experiments the rate of lamina growth per tiller increased linearly with an increase in sward surface height and herbage mass. In the two experiments conducted in July–August this relationship was partially offset by a linear increase in the rate of senescence per tiller but net production per tiller also increased linearly in relation to sward height and mass. In the experiment conducted in May–June the rates of growth and senescence per tiller increased in parallel so that net production per tiller showed no relationship with sward condition.Tiller population densities in the July–August experiments were highest in swards maintained between 2 and 3 cm surface height and declined in swards maintained above and below this height. In the experiment in May–June tiller numbers were similar in all treatments prior to the summer solstice but diverged in a manner similar to the other experiments later in the year.The rate of lamina growth per unit area increased in a manner consistent with an asymptotic relationship and the rate of senescence increased linearly with increasing sward height and mass in all three experiments. Net production per unit area was reduced on swards below about 2.5 cm in height but was insensitive to variation in sward surface height between 2.5 and 6.0 cm (approximately 1000–2500 kg OM ha−1 herbage mass).The effectiveness of adjustments in tiller numbers and production per tiller and of changes in the balance between growth and senescence as mechanisms of sward homeostatis, together with their implications in the scope for manipulating herbage production by grazing management are discussed briefly.

Notizen: There was a three-fold variation in epicuticular wax content between populations of white clover and a five-fold variation between populations of red clover. The mean for all populations of red clovers was twice that of white. There was also a two- to three-fold variation within each population.The epicuticular wax content of white and red clovers grown in the field showed an increase with age. Thin layer chromatography showed no qualitative differences in the epicuticular waxes extracted either between populations or with sampling date.The higher levels of epicuticular wax found in some clovers were considered to be of possible significance as a source of antifoaming compounds in bloat-inducing pastures.

Notizen: Differences in ease of digestion of bundle sheath cell walls of leaf blades of Panicum spp. are shown to be associated with differences in bundle sheath cell wall structure, including the presence or absence of a suberized lamella. These structural differences are correlated with photo-synthetic type (viz. C3, intermediate C3/C4, and the C4 types, PCK, NADP-ME and NAD-ME), as are mesophyll: bundle sheath area ratios.

Notizen: The construction of a transducer and the use of a recording system to measure jaw movements of grazing sheep is described, The time spent grazing, ruminating and idling may be measured by this equipment and the data produced automatically processed using a microprocessor which determines each minute whether the animal is grazing, ruminating or idling and also summarizes these data to give total times. The accuracy of this technique in relation to manual observation is discussed.

Notizen: The effect of two heights of cutting (5 and 8 cm) on the dry matter harvested and persistency of a range of different grass species and varieties were monitored over a 3-year period (1976 to 1978). Dry matter harvested was measured in the second and third harvest year and persistence of sown grass was assessed at the end of the first and third harvest year. The grasses were managed under a frequent cutting system, i.e. simulated grazing. Results showed that at the low cutting height tetraploid hybrid ryegrasses and diploid Italian ryegrasses in the third harvest year gave lower annual dry matter harvests of sown grass and were less persistent than at the high cutting height, whilst, in contrast, perennial ryegrasses gave higher annual harvests of sown grass but persistency was unaffected. In general at the low cutting height varieties of cocksfoot, meadow fescue and tall fescue gave comparatively higher annual harvests of sown grass in the second harvest year but lower yields of sown grass in the third harvest year. A notable exception was Cambria cocksfoot which in the second harvest year gave higher yields of sown grass and was more persistent at the low cutting height.However, at 5 cm cutting height, the proportions of weed grasses (mainly Poa spp.) in swards sown to tetraploid hybrid ryegrasses and diploid Italian ryegrasses were generally greater, particularly in mid-season.

Notizen: Laminae of Lolium perenne and Phleum pratense were tested mechanically and the results analysed using engineering composite theory and fracture mechanics. As the lamina dries the fibres double in stiffness. The intervening cells show a sevenfold increase in stiffness below 20% water content (based on dry weight). Work to fracture across the veins is almost independent of water content, but below 50% water content the mode of fracture changes. It is predicted that total fibre content will not affect hay shatter; total protein content may affect it by altering the water-binding properties.

Notizen: Grass silages made from first-harvest perennial ryegrass in mid-May and early-June and termed high-D and low-D respectively had mean DOMD values of 694 and 633 g kg−1 and were offered ad libitum to twelve Ayrshire cows in a 16-week feeding experiment using a cyclic changeover design. The silages were supplemented with a concentrate containing 363g CP per kg DM at daily rates of 1.5, 3.0 and 4.5 kg per cow. The average daily intakes of silage DM were 12.6 and 11.1 kg per cow on the high- and low-D silage treatments respectively, and were not significantly different on the three concentrate treatments. The mean daily milk yields were 171, 18.6 and 21.0 kg per cow on the low-D silage treatments, and 19.6, 21.2 and 22.8 kg per cow on the high-D silage treatments at the 1.5, 3.0 and 4.5 kg rates of concentrate feeding respectively. Fat and lactose concentrations in the milk were not affected significantly by treatment, whereas the CP and SNF concentrations increased progressively and significantly as the rate of supplementary feeding increased. It is concluded that a high-protein concentrate supplement allows silage to make the maximum contribution in the diet, and gives a high response in terms of milk yield and composition.

Notizen: Grass which had grown without interruption from late April was cut as for hay in early July in each of 2 years. Fifteen dates of removal of the cut herbage were compared ranging, at 1-d intervals, from the day of cutting to 14 d after cutting. Sward regrowth was studied.A delay of 5 d in removing cut herbage reduced herbage dry matter harvested during the remainder of the growing season by 9% and a delay of 10 d reduced yield by 16%. Delaying the removal of cut herbage reduced the density of grass tillers considerably in the short term, but the effect had worn off in 8 to 12 weeks. The presence of cut herbage reduced the rate of extension of leaf blades considerably. Delaying the removal of cut herbage reduced the area per leaf blade and the weight per unit area and these effects persisted for several weeks. Grass growing under cut herbage had a less negative leaf water potential and a rather cooler but much darker environment in which to grow than uncovered grass.

Notizen: Book reviews in this article: Milk from Grass Edited by C. Thomas and J. W. O. Young Nitrogen Fixation in Legumes Edited by J. M. Vincent Herbage Intake Handbook Edited by J. D. Leaver Man's Proper Study By Richard J. Colyer Introduction to Sheep Fanning By R. G. Johnston

Notizen: Information about the grazing behaviour and the return of dung to pasture by lactating dairy cows was collected from stocking rate experiments in northern Victoria. Grazing behaviour was observed for 24-h periods in mid-summer in two years. Grazing time increased as herbage allowance decreased to about 32 kg DM cow−1 d−1 but as herbage allowance decreased further grazing time also decreased. A herbage allowance of 32 kg DM cow−1 d−1 corresponded to a stocking rate of about 5.5 cows ha−1. This effect of herbage allowance on grazing time may have been confounded by herbage mass, however. Rumination time of the cows increased by 003 h for each kg increase in herbage allowance while resting time was not affected by treatment.The effects of stocking rate on some of the characteristics of faecal output were measured for a 3-d period in mid-summer. The number of pats deposited per cow daily declined by 0.66 for each unit increase in stocking rate. The fresh weight of dung also declined as stocking rate increased by 0.16 kg per unit of stocking rate. While the values for the amounts of dung deposited on the pasture by the cows at the lower stocking rates are similar to many of those reported in the literature, this study has quantified the way in which stocking rate may influence this in one instance. Furthermore, provided that some measure of herbage intake is made when measurements of dung excretion are performed, it is suggested that estimates of in vivo digestibility can be obtained.

Notizen: Two red clover (Trifolium pratense) cultivars, Red Head (tetraploid) and Kuhn (diploid), were sown at a seed rate of 13 kg ha−1 either alone or in mixture with Italian ryegrass (Lolium multiflorum) cv. RvP sown at seed rates of 10, 15, 20 or 30 kg ha−1. RvP was also sown alone at a seed rate of 30 kg ha−1 and received nil or 300 kg ha−1 fertilizer a−1 fertilizer N. All plots were established using the barley cultivar Midas sown at a seed rate of 100 kg ha−1 as a nurse crop.Neither clover cultivar nor ryegrass seed rate significantly influenced either dry matter harvested or botanical composition over the 3 harvest years. On average over all years the grass-clover mixtures produced 75% of the yield of the N-fertilized RvP, 125% of the clover monocultures and 225% of the unfertilized RvP. The red clover contribution to the total dry matter harvested of the mixtures averaged 45–60%. The dry matter concentrations of the mixtures were considerably higher than those of the pure clover stands. In the third year yields were markedly reduced in comparison with those in the first and second years.It was concluded that Italian ryegrass can be a suitable companion grass for red clover. Its superior yielding capacity over other grasses such as perennial ryegrass or timothy under a conservation management can be coupled to advantage with red clover to give a sward which Is essentially stable, at least over a 2- to 3-year cropping period, although giving slightly reduced yields in the third year. Italian ryegrass-red clover mixtures, without the use of fertilizer N, can produce high DM yields of good quality herbage.

Notizen: Red clover cv. Hungaropoly was slot-seeded into a perennial ryegrass-dominant sward in April 1979. Glyphosate and paraquat were applied separately as bandsprays each at two doses and at two band widths. Control plots were either slot-seeded without a herbicide bandspray or received ±150 kg N ha−1 a−1. Red clover establishment was assessed and amounts of dry matter (DM) and total N accumulated were measured at two harvests in 1979 and three harvests in 1980. Bandspraying increased seedling vigour and development and resulted in the eventual replacement of 1 t grass DM ha−1 by an equivalent amount of red clover. Of the treatment variables investigated, bandspray width had the greatest influence on red clover establishment and productivity. The slot-seeded area, meaned for all treatments, produced a total of 6.40 and 13.16 t DM ha−1 in 1979 and 1980. This was estimated to be equivalent to the all-grass sward receiving 112 kg N ha−1 a−1 during the second year of the experiment or 238 kg N ha−1 over the 2 years when measured in terms of N yield. Slot-seeding overcomes several of the problems associated with conventional establishment of red clover.

Notizen: Two experiments were conducted to determine the effect of pre-harvest treatment by formic acid spray on the moisture concentration (MC) of perennial ryegrass (Lolium perenne) in vegetative growth. In Experiment 1 aqueous solutions containing 0.080, 0.148 and 0.259 kg formic acid per litre were applied to a perennial ryegrass sward (fresh matter yield 21.0 t ha−1) at a constant volume of 41.2 litres t−1to give active ingredient application rates of 3.5, 6.0 and 11.5 kg t−1 respectively. In Experiment 2 similar solutions were applied to a perennial ryegrass sward (fresh matter yield of 6.9 t ha−1) at 35.2, 19.0 and 10.9 litres t−1 respectively to give a constant formic acid application of 2.8 kg t−1. The changes in MC and chemical composition after treatment with acid were compared with those in untreated plotsIn both experiments treatment with acid significantly reduced the MC (P 〈 0.001) within 5 h of treatment from 4.4 to 3.0 kg per kg of dry matter (DM) in Experiment 1 and from 3.0 to 2.6 kg per kg DM in Experiment 2. There was no effect of level of acid applied in Experiment 1 or of the volume of water applied with the low level of acid in Experiment 2 on the changes in MC of acid-treated plots. There was however a significant (P 〈 0.00l) difference between the MC of plots treated with acid and those untreated which was maintained in Experiment I for up to 9 d even during rainfall.There were no differences between the chemical compositions of samples from acid-treated plots in either Experiment I or 2 or between untreated and acid-treated plots in Experiment 2. However there were significant differences between untreated and acid-treated plots in Experiment 1 for the content of nitrogen (N), water-soluble carbohydrate (WSC) and digestible organic matter (DOM). There were changes in the content of N, WSC and DOM with time in both experiments. In Experiment I there was an interaction between sampling time and treatment for both N and WSC but not for DOM. Compared with untreated plots, treatment with acid at all levels accelerated the loss of WSC and delayed the fall in N content. There were no such interactions in Experiment 2.

Notizen: The main object of the experiment was to assess the effect of the relative proportion of non-protein nitrogen (NPN) to total nitrogen in silage on digestion in the sheep. Four unwilted perennial ryegrass silages were made with the addition of formic acid at 0, 2·2, 4·2 and 5·2 litres t-1 to provide foods with NPN proportions reducing from 0·26 to 0·20 of the total N. The digestion of the silages was studied in a 4 × 4 Latin Square experiment with sheep cannulated in the rumen, proximal duodenum and terminal ileum.Results for organic matter (OM), cellulose and N showed no major difference between silages in their digestion in the rumen, small intestine and caecum and colon, though small differences (P 〈0·25) in rumen fermentation pattern and in the proportion of digestible OM disappearing in the small intestine were observed. Concentrations of ammonia N in the rumen and rates of rumen bacterial protein synthesis did not differ significantly between silages and there were no treatment effects on the passage of individual amino acids to the small intestine. The results indicate that the proportions of NPN to total N in the silages examined had little influence on the efficiency of silage N utilization in the rumen or on the passage of undegraded dietary protein to the small intestine.

Notizen: Two experiments were carried out to determine whether the differences in intake and feeding value previously shown between two grass cultivars when offered to ruminants as chopped artificially dehydrated (dried) material could also be demonstrated when the grasses were offered in other forms. Two cultivars of tetraploid Italian ryegrass (Lolium multiflorum), Sabalan and Tetila, were established in the same field in 1975. In 1976 they were grazed and conserved (two cuts of primary growth) as dried material or as silage.The composition of the herbage selected at pasture and conserved showed higher concentrations of normal detergent fibre and acid detergent fibre in the dry matter for Tetila than for Sabalan, but differences between cultivars in digestibility were small. In both grazing and winter feeding trials differences in voluntary intake between the two cultivars were not significant, but at pasture young beef cattle spent less time grazing and tended to spend more time ruminating on Tetila than Sabalan. There was no measure of animal performance at pasture but liveweight gain was 15% higher for Sabalan than Tetila when both were offered to young beef cattle as the sole feed of dried grass or of silage. The voluntary intakes of the three forms of feed were very similar, which in part reflected a similarity in digestibility. However, gains were lower for calves given silage than those given dried grass. This may have been due to a lower efficiency in the utilization of the nitrogeneous components of silage for tissue growth than those of dried grass.

Notizen: Four grass silages, all made in mid-July from second-harvest perennial ryegrass swards, were compared in a 16-week feeding experiment with twelve Ayrshire cows. Two silages were unwilted and two wilted. All the silages received formic acid (‘Add-F’) at the rate of 3 litres t-1 either with formalin at the rate of 1 litre t-1 or without formalin. The unwilted and wilted silages had mean dry matter (DM) concentrations of 200 and 243 g kg-1, and in vitro D-values of 0·293 and 0·272 respectively. The silages were offered ad libitum plus 6 kg concentrates per cow per day. The daily intakes of unwilted and wilted silage DM were 10·2 and 9·2 kg per cow respectively on the formic acid treatment, and 10·2 and 9·2 kg on the formic acid + formalin treatment. The mean daily milk yield on the unwilted silage treatments was 19·2 kg per cow which was significantly higher than the yield of 17·2 kg per cow on the wilted silage treatments. The formalin had no significant effect on milk yield. The four silage treatments had small and non-significant effects on milk composition. It is concluded that the unwilted silages, which had excellent fermentation characteristics, were superior to the wilted silages as a feed for dairy cows.

Notizen: Book review in this article Forage Evaluation: Concepts and Techniques Edited by J. L. Wheeler and R. D. Mochrie Improved Feeding of Cattle and Sheep By P. N. Wilson and T. D. A. Brigstocke Nitrogen Cycling in West African Ecosystems Edited by T. Rosswall Land Evaluation By S. G. McRae and C. P. Burnham

Notizen: Three field experiments showed that perennial ryegrass can be successfully slot-seeded into an existing Festuca-Agrostis sward. Ryegrass survival was satisfactory in all cases but was improved on a low fertility site by the application of fertilizer N, P and K in the slot at sowing.The effect of varying inter-row spacing from 37·2 to 15 cm was measured in a 3-year experiment. In year one, involving seven cuts, slot-seeding increased total herbage dry matter harvested by a mean value of 17%; inter-row distances of 22·2-30 cm gave the optimal combination of ryegrass + old sward herbage. Differences in yield between inter-row spacings declined in the subsequent two years, as the rows of ryegrass thickened. Ryegrass digestibility (measured only in year two, from six cuts) was higher than that of the old sward; total metabolizable energy harvested from 15-cm rows was 20% higher than that from unsown controls. Increasing N input from 200 to 400 kg ha-1, starting in year two, only produced a significant increase in total herbage harvested in year three but proved effective in increasing the ryegrass contribution from the wider spaced rows.

Notizen: In three separate feeding experiments using a total of thirty individually-housed Ayrshire cows three silages made from perennial ryegrass were given ad libitum together with supplements of four different hays in the long form. The in vitro D-values of the silages ranged from 0·298 to 0·283, and the hays from 0·280 to 0·200. The daily intake of hay DM varied from 0·2 to 4·2 kg per cow and was given either without or with a daily maximum of 2·2 kg concentrate DM containing 379–527 g CP per kg DM. On average, 1 kg hay DM decreased silage intake by 0·24 kg DM with a range of 0·21–1·20 kg. The hay supplements had only small and non-significant effects on total DM intake, milk yield and milk composition, but increased the daily intake of drinking water. In three behavioural studies, the eating and ruminating times expressed as min per kg DM did not differ significantly between the various supplement treatments. It is concluded that hay has only a marginal value as a supplement for grass silage, although the hay could serve as a useful ‘buffer’ feed if the amount of silage was limited.

Notizen: Two areas of an early-heading perennial ryegrass cv. Cropper were harvested by either a precision-chop or a flail harvester at around 50% ear emergence (15 May 1978) and 14d later (29 May). Formic acid (85%) was applied at the rate of 2·2 litres t-1. Mature crossbred wethers were used in a 2 × 2 factorial design to determine the effect of stage of maturity and method of harvesting (chop length) on the in vivo digestibilities of formic acid-treated grass in experiment 1 and formic acid silage in experiment 2. Apparent digestibility coefficients were determined at a fixed level of feeding for both grass and silage and at ad libitum access to feed for silage only.There were no significant differences in the concentrations of crude protein (CP), ether extract (EE), acid-detergent fibre (ADF) or acid-detergent lignin (ADL) in grass or silages of differing chop lengths but the later cut forages had significantly higher ADF and ADL concentrations and lower CP concentrations than the early-cut forages. The ADF and ADL concentrations were also higher in the silages than in the corresponding grasses.In general, the fermentation characteristics of precision-chopped silage were better than for the corresponding flail-cut silage but date of harvest was a more important determinant of quality and the late, flail-cut silage had the highest butyrate and ammonia N concentrations and the highest pH (411) of any treatment. There was a significantly higher intake of precision-chopped as compared with flail-cut silage with both the early-and the late-cut silage but there were no significant differences attributable to stage of maturity (i.e. date of harvest) or significant interaction between chop length and maturity. The slightly increased intake of early harvested, precision-chopped silage as compared with late precision-chopped silage was not significant.Dry matter digestibility (DMD) of the grass decreased at a rate of 0004 units d-1 post 50% ear emergence. The results of experiment 2 indicated a decrease of 0·207 units d-1 in silage fed at a similar level. The late-cut silage (DMD 0·292, mean of both harvesting treatments) thus had a significantly lower digestibility than the corresponding grass (mean DMD 0·247). Chop length had a variable influence on the DMD of both grass and silage fed at a fixed level but treatment differences were non-significant. However, a trend towards higher digestibility of flail-cut as compared with precision-chopped silage was apparent and this became statistically significant when the animals were allowed ad libitum access to feed. This may be a response to the generally lower intake of flail-cut silage.

Notizen: Book review in this article Weed and Pasture Management in South Africa Edited by N. M. Tainton Collecting and testing tropical forage plants Edited by R. J. Clements and D. G. Cameron Herbage Intake by Grazing Dairy Cows By J. A. C. Meijs

Notizen: Two experiments were carried out to evaluate propionic acid-treated hay as a feed for sheep in which eighteen ewes (experiment 1) and eighteen ewe lambs (experiment 2) were fed ad libitum on hay only. At feeding, the propionic acid-treated hays had higher D-values and water-soluble carbohydrate concentrations, but a lower dry matter concentration, than the untreated hays. The voluntary feed intake and liveweight gain of the sheep fed on two acid-treated hays and on an untreated hay in experiment 1 were similar. In the second experiment an acid-treated moist hay was eaten in greater amounts by the sheep and liveweight gains were greater than on the corresponding untreated hay, but were not significantly different from those of sheep fed on field-cured hay.

Notizen: Six varieties of white clover, each grown with perennial ryegrass, four intervals between cuts and two levels of applied nitrogen in all combinations, were compared in a field experiment during the first 27 months after sowing. Information about yields, crop fractions, heights and ryegrass tillers has been presented in an earlier paper (Wilman and Asiegbu, 1982). The present paper is concerned with the more detailed studies of white clover, which help to explain the yield results and contribute to the understanding of the response of this species to management when grown in competition with grass.Increasing the interval between harvests increased the length of clover stolon per unit area of ground and increased stolon diameter, petiole length, weight per leaf and number of leaves harvested as a proportion of the number present in the sward while only slightly reducing the rate of leaf emergence, helping to explain the positive effect of increasing the interval on clover yield noted in the earlier paper. During regrowth, successive leaves had longer petioles and the length of individual petioles increased beyond the stage at which the leaflets were fully opened. Weight per leaf in clover increased considerably from April to June and declined to below the April value by October. It was shown that weight per leaf can be greatly increased by increasing the interval between harvests without reducing the number of leaves harvested per unit area per year. The stolon length measurements provided some support for the view that medium large-leaved varieties of white clover can with advantage be defoliated rather less frequently than small-leaved varieties. Stolon length was less adversely affected by applied N in the medium large- than in the small-leaved varieties. The small-leaved varieties had thinner stolons than the medium large-leaved varieties but about twice the stolon length when no N was applied, and a relatively high proportion of leaves which escaped defoliation. The application of N reduced stolon diameter, increased petiole length and had little or no effect on weight per clover leaf.

Notizen: Data from twenty-two comparisons carried out at ADAS Experimental Husbandary Farms are used to compare untreated and formic acid-treated silages. Additive treatment led to an improved fermentation in some crops, particularly those of low DM concentration (〈262 g kg-1). Where this occurred there were associated benefits in silage digestibility (+0·234 units), intake (+16%) and the growth rate of young cattle (+0·28 kg d-1). Where the fermentation of the untreated silage was good, both digestibility and animal performance associated with treated and untreated silages were similar. It is suggested that the justification for using formic acid in a commercial situation is thus restricted to occasions where the untreated crop would be liable to develop a clostridial fermentation. These may be when crops contain less than 35 g water-soluble carbohydrate kg-1.

Notizen: The change in structure of continuously grazed versus infrequently cut swards of perennial ryegrass (Lolium perenne L), cv. S23, was investigated during their first full harvest year. Measurements were made from early May until late September. The intensity of stocking by sheep in the grazed sward was adjusted in an attempt to maintain a high level of radiation interception and the cut sward was harvested at approximately monthly intervals.The herbage mass, lamina area index and radiation interception of the cut sward varied in a cyclic pattern between harvests but in the grazed sward these parameters showed considerably less variation, although they all increased early in the season and then declined later. The proportion of dead material above ground increased throughout the season in both sward types but was more marked in the grazed sward.There were major differences between the grazed and cut swards in the number of tillers per unit ground area; the difference became more marked throughout the season and by September the tiller densities in the grazed and cut swards were 3·204 m-2 and 6·203 m-2 respectively. Divergence in tiller density was associated with differences in specific stem weight and leaf area per tiller.Rates of appearance and death of leaves on tillers in the grazed sward were determined. During May, leaf appearance exceeded leaf death but this was reversed in June. During the rest of the season as a new leaf appeared on a tiller so the oldest leaf died.

Notizen: A rising-plate meter was used in a double sampling technique to measure the herbage mass of rotationally grazed perennial ryegrass-white clover swards over a period of 2 years. The meter was calibrated by developing a linear regression between meter reading and herbage dry matter mass as measured by cutting 0·2-m2 quadrats to ground level.There was a strong relationship between meter reading and herbage mass, and correlation coefficients were consistently 0·2 or above. The calibration regression was normally constant for extended periods, especially over the winter and spring. The relationship was more variable over the summer but appeared to follow a pattern that was to some extent repeatable between years. The slope of the regression (kg DM ha-1 cm-1) was 312 and 267 in the two winters and reached values of 800 and 452 in the two summers. The calibration relationship was adequately described by a linear model over the winter and spring but there was a tendency for a curved relationship in mid-to late summer.The standard pooled regression found with winter ryegrass-clover swards was not applicable to the more erect prairie grass, and the standard regression overestimated slightly the yield of heavily grazed swards. There was no evidence of a difference in relationship between irrigated and non-irrigated swards over the summer.The individual meter readings could be used to develop a useful diagrammatic picture of the changes that occurred in sward structure as the pastures were subjected to different managements and this could be used to illustrate problem areas in pasture management.The meter was useful in overcoming the problem of variability of herbage mass within paddocks and could give precise estimates of herbage mass, especially when it was possible to use a pooled regression encompassing a large number of calibration cuts. In these cases the meter could be used to detect differences of about 8%.

Notizen: A novel hybrid stubble turnip, Appin, bred by the Scottish Plant Breeding Station (Brassica campestris ssp. rapifera cv. Tigra ×B. campestris ssp. nipposinica cv. Mizuna) was compared in small-plot cutting trials with stubble turnip (B. campestris ssp. rapifera cv. Ponda), forage rape (B. napus ssp. biennis cv. Canard) and fodder radish (Raphinus sativus cv. Neris) for 3 years, 1975–77, samples being taken from October to December or January each year to cover the likely period of utilization by grazing lambs. Except for the first year, Appin proved to yield less DM than Ponda, and be inferior in digestibility and metabolizable energy (ME) content, though N contents were on occasion higher. Canard had the highest overall ME content. In dry conditions in autumn 1977, Ponda proved the more reliable crop, suffering less depression in yield than other species. Anti-metabolite contents were determined in freeze-dried samples taken in winter 1976-77 and showed Canard to have the most brassica anaemia factor (S-methyl cysteine sulphoxide): contents of thiocyanate were generally similar between crops.As the degree of utilization of such forages when grazed can outweigh differences in recorded above-ground DM yields from cutting trials, it was considered that claims of better root anchorage and hence better utilization for Appin warranted evaluation in a grazing trial.

Notizen: Two grass silages made from perennial ryegrass, and with D-values of 0·216 and 0·255, were offered ad libitum to 18 Ayrshire cows in two feeding experiments. On the control treatment the silages were supplemented with soybean meal only, and on the other two treatments with equal weights of DM from either barley or dried molassed sugar-beet pulp plus the same weight of soya as on the control treatment. The daily intakes of silage DM were not significantly different on the barley and beet-pulp treatments, and, on average, the intake of silage DM was reduced by 0·24 and 0·20 kg by feeding 1 kg barley and beet pulp DM respectively.The daily milk yields were not significantly different on the barley and beet-pulp treatments with mean values of 19·2 and 19·2 kg per cow respectively compared with 17·2 kg on the control treatment. On the barley and beet-pulp treatments the fat, SNF, CP and lactose concentrations in the milk and the live weights of the cows were not significantly different. It is concluded that the barley and beet pulp had similar feeding values and replacement rates when used as supplements with grass silage, and that the two feeds were interchangeable on an equal DM basis.

Notizen: An experiment examining the relationship of daily herbage disappearance (DHD) and daily herbage allowance (DHA) is described. Cows with calves were grazed at three stocking rates on Kleingrass and Coastal Bermudagrass pastures. DHD and DHA were monitored at 14-d intervals. A significant positive linear relationship was noted between DHD and DHA (P〈inlineGraphic alt="leqslant R: less-than-or-eq, slant" extraInfo="nonStandardEntity" href="urn:x-wiley:01425242:GFS9:les" location="les.gif"/〉0·25). Equations derived for Coastal Bermudagrass and Kleingrass were not significantly different and resulted in a combined equation Ŷ= 0·275X + 0·209 with an r2 vaiue of 0·27. As DHA exceeded 6–9 kg DM per 100 kg live weight, efficiency of defoliation by the cows and calves declined.

Notizen: The effects of five herbicides on seed yield and viability of perennial ryegrass cv. S24 were tested at two sites. Benzoylprop-ethyl, chlorfenpropmethyl, difenzoquat, ethofumesate and flam-prop-isopropyl were safe to use at doses recommended for use in other crops. When applied at three times the recommended dose, only difenzoquat reduced the yield and germination of seed and benzoylprop-ethyl reduced seed germination. The recommended doses of difenzoquat and ethofumesate were safe when applied on cv. Barlenna at different growth stages. Difenzoquat reduced seed yield only after three times the recommended dose was applied to tillered plants. Ethofumesate, even at three times the recommended dose, did not affect seed yield but plant numbers were reduced by early treatment. The results suggest that the herbicides tested may be safe to use in perennial ryegrass seed crops at the recommended doses but more work is needed on the safety of difenzoquat in relation to crop growth stage.

Notizen: Over a 3-year period the productivity of perennial ryegrass (Lolium perenne L., cv. S24) swards as influenced by variations in the time of initial defoliation and close (2·5 cm) and lax (8 cm) defoliation was studied. Treatments with initial defoliations in the early vegetative stage, stem elongation and flowering stages of growth gave higher annual yields than treatments in which the initial defoliation was taken at an intermediate stage of growth when the majority of the stem apices had just been elevated above the height of defoliation. Initial defoliation treatments which removed a high proportion of apical meristems while the yield at the initial defoliation was still low produced the lowest annual yield. Consistent lax defoliation reduced yield by 14·5% compared with continual close defoliation. However, taking an initial lax defoliation followed by subsequent close defoliations produced a slight yield advantage of 4·8% over consistent close defoliation. The results are discussed in relation to other research findings and the practical implications commented upon.

Notizen: Estimates of the total acidity of silage effluent from a range of first-cut silages varied from 1025 to 21,125 mg Ca CO3 per l with a weighted mean of 8817 mg l-1. Quick-lime (CaO), hydrated lime [Ca(OH)2] or caustic soda (NaOH) were found to be effective neutralizing agents when thoroughly mixed with the effluent. Results from seven field-plot experiments carried out between 1973 and 1977 involving application of silage effluent to grass swards are reported. Leaf scorch occurred when silage effluent with a total acidity equivalent to more than 6000 mg CaCO3 per l was applied at rates exceeding 50 m3 ha-1 to swards with several weeks regrowth. Scorch was most severe when applications were made during periods of dry sunny weather and to mechanically damaged swards. In these conditions reducing the total acidity to below 2000 mg CaCO3 per l by neutralization or dilution allowed rates of over 100 m3 ha-1 to be applied without harmful effects.Acid neutralization was found to be unnecessary when silage effluent was applied to recently cut swards. Here rates of up to 150 m3 ha-1 were applied without adverse effects and generally resulted in increased grass growth.

Notizen: The frequency and severity of defoliation of small sample areas, 8 × 8 cm, was studied in swards of S37 cocksfoot which were maintained at different levels of leaf-area index by continuous grazing with lambs. By varying the number of lambs grazing a plot, the LAI was maintained at three approximately constant levels, 5.3 (H), 4.1 (M), and 3.0 (L). Any one 8 × 8 cm area was grazed on average once every 36 days in treatment H, 24 days in treatment M and 19 days in treatment L. Approximately 24% of the total length of leaf present per tiller was removed each time a tiller was grazed, under all treatments. The lambs tended to graze patches of herbage about 16 × 16 cm, then move to a different place in the sward. These results are discussed in relation to grazing practices aimed at securing the maximum harvested yield.

Notizen: The potential for producing beef in savanna grassland areas is discussed in relation to the results obtained from grazing trials on sown pastures at Serere Research Station, Uganda. Liveweight gains from small East African Zebu stock are used to illustrate the progress that has been made in the selection of improved pasture species and mixtures grown at various levels of fertilizer application. The utilization of herbage from selected pastures is shown to vary under different grazing management systems, grazing pressure having the greatest effect upon animal production. The need for further investigations and the integration of existing research findings into farming practice is stressed.

Notizen: Book reviewed in this article:LANGER, R. H. M. [Ed.] The luceme crop.FRYER, J. D.; EVANS, S. A. [Eds] Weed control handbook.RODIN, L. E.; BAZILEVICH, N. I. Production and mineral cycling in terrestrial vegetation.

Notizen: A number of experiments are reported in which comparisons were made, using calves, or ewes and lambs, between Tetila Tetrone and S22 or Danish Italian rye-grasses or between Reveille and S24 perennial ryegrasses.In general, the differences over the whole growing season were not large, but grazing experiments with calves during 1963-5 all showed that a substantial advantage in live-weight gain, can be obtained in the later part of the grazing season (July to September) by using T. Tetrone rather than S22 or Danish Italian ryegrasses.

Notizen: By controlling the high populations of leatherjackets in two experimental leys it was shown that the loss of grass from this pest could be heavy. The most serious loss occurs in early summer. As soon as the larvae cease feeding in mid-June recovery begins and subsequent growth is satisfactory. Clover is damaged more heavily than grasses, but recovers completely by early autumn. The implications of these experiments are discussed.

Notizen: Two experiments are described in which data were collected on yield, floral characteristics and winter greenness of a number of indigenous hill grass species. Differential cutting treatments, besides affecting total yield, affected yield and floral vigour in the subsequent year. Differences in sensitivity to cutting were present among the species. The date at which the grasses were last cut in autumn affected their winter greenness though responses differed among species. The significance of these results in relation to performance and management of hill pastures is discussed.

Notizen: The growth curves of closed grassland swards obtained during the growing seasons of six successive years were compared with each other and with theoretical growth rates calculated by de Wit's method and based on the mean light energy input data for the same years. The form of the growth curve consisted of a period with a constant rate, lasting for 6–7 weeks in May-June, then rapidly shortening to 3 weeks in August-September, after which there was a rather abrupt change to zero values. A comparison with theoretical values showed that a period of constant growth rate was possible, because the promoting influence of increasing LAI counteracted the effect of increasing respiration. Before the longest day this period was lengthened by an increasing daylength; thereafter the reverse was found. There is no ready explanation for the sudden decline to zero values. This is thought to be associated with changes in the rate of photosynthesis.

Notizen: In two experiments the growth of clover undersown to wheat was linearly related to the amount of light available. There were strong indications that clover growth and light within N.-S. rows were superior to those within E.-W. rows of wheat, and within N.-S. rows, those along the middle position were superior to others. The large difference between the growth of clover sown alone and with wheat indicated that beneath wheat the clover suffered from competition for other factors, probably soil moisture, which was even greater than that for light. Beneath wheat at the reduced level of growth there was a positive linear relationship between yield of clover and available light.

Notizen: Two pot experiments were carried out in a semi-controlled environment to examine the response of individual plants to competitive stress in simple systems incorporating varying cutting frequencies and soil–nitrogen levels. A third experiment was set up outdoors to examine the effect of competition on individuals in an association, on the association as a whole, and to extend the controlled environment studies to a more complex model involving micro-plots. Phalaris coerulescens, although its seedlings possessed a high competitive ability, showed a dramatic decline in competitive ability in later stages of the association, this decline being associated with extensive floral development. In micro–plots the effect of competition was so severe as to prevent the expression of seasonal growth characteristics by P. coerulescens.Considerable inter-specific differences existed in the response to competition of leaf-area production per tiller during periods of regrowth.Whilst P. coerulescens remained highly productive and maintained a dense tiller population in monocultures, its tiller regeneration following flowering was severely suppressed in competition with vegetative plants of HI ryegrass or Festuca arundinacea.The number of heads produced per plant, head length and time of head emergence were all affected by competitive stress, the former response being a reflection of the relative competitive abilities at the time of floral initiation. The response of the latter two characters reflected the decline in competitive ability which occurred during later stages of the growth and development of P. coerulescens.

Notizen: The use of lime and phosphates in reclaiming heather moorland was investigated in two experiments.Large initial dressings of hme resulted in a rapid rise in pH. An initial dressing of 9 tons CaCO3/ac resulted in a more rapid rise to pH 6 than did 6 tons/ac and the soil was maintained above pH 6 for a longer period. Three annual dressings of 3 tons/ac gave a slower rise in pH and a longer period above pH 6. Split treatments, half before and half after the first ploughing, gave no long–term advantage where a programme of pioneer cropping was being followed.Basic slag and North African phosphate were as effective as superphosphate for root crops at low pH values. Basic slag was as effective as superphosphate for grassland establishment and gave a greater rise in soil phosphate. North African phosphate was virtually worthless as a source of phosphate for establishing grasses and clovers, and gave a negligible rise in soil phosphate.Given adequate supphes of lime and phosphate, frequent small apphcations of N over the first 2 or 3 years are vital to the success of a reclamation programme under the conditions described.

Notizen: There was a marked increase in basal cover of veld grasses after the first 2 to 3 years of cutting, and this effect continued over a period of 9 years. Short grasses, such as Cynodon dactylon and Heteropogon contortus, increased at the expense of tall tussock grasses, such as Hyparrhenia dissoluta.

Notizen: Two experiments were established to compare the effect on the yield of continuously cut herbage of varying amounts of potassium fertilizer applied either in one large dose to the seedbed, or as 3 equal dressings applied to the seedbed and in the summer of the 2 following years. Responses in dry–matter yield were recorded up to the higher rates of potassium fertilizer applied. Establishment and yield in the first 12 months were improved by seedbed applications of up to 4 cwt/ac of muriate of potash (60% K2O). Although total yields over the whole period were similar, whether the potassium was applied to the seedbed only or in annual dressings, yields from “all–in–seedbed” dressings declined towards the end of the period. Soil analysis indicated that annual dressings left behind higher residues of K.

Notizen: During the winter months of 1963 and 1964, mature non–pregnant Clun Forest ewes at pasture were equipped with pedometers to study the value of these instruments for measuring distances walked, and to investigate the importance of weather on the distances travelled. Approximately 80 periods were recorded, each of about 24 hours. The accuracy of the measurements was checked by using a rangemeter and it was found that the reliabihty of pedometer records must be assessed on the animal from which they are obtained. The individual characteristics of the pedometers and/or the sheep gave rise to inaccurate records from about 50% of the instruments studied.Multiple regression analysis of data for each of the three sheep which provided suitable records revealed that, in dry weather, the average distance walked per hour of recording period increased signiJBcantly with mean air temperature in one case and with hours of bright sunshine in another. Wind–speed effects were unimportant. The distance walked by all three sheep increased significantly with hours of daylight per recording period, and this was the only variable found to affect distance walked in wet weather. Differences between average distances walked per hour under dry–and wet–conditions were non–significant.It is concluded that for measuring the distances walked by sheep, the disadvantages of the pedometer outweigh its advantages.

Notizen: Methods of testing grass varieties are discussed and the efifects of differences in management and of nitrogen fertilizer on quality are shown. In a grazing-management system with 9 cuts per season, cocksfoot was higher than perennial ryegrass in protein and fibre and lower in soluble-carbohydrate content and in vitro dry-matter digestibility throughout the season. All species showed the lowest value for digestibility in August.Curves for digestibility in primary growth were plotted for 4 varieties of ryegrass for leaf and stem fractions. The tetraploid variety Reveille was slightly more digestible than S24 in leaf and stem throughout the period, while at ear emergence S23 was lower in digestibility in both fractions than S24.There were significant differenees in composition and digestibility between experimental centres, but relative differences between varieties were consistent. The level of N fertilizer did not materially alter the comparison between varieties in quality data.

Notizen: A series of experiments in eastern Scotland, carried out over a 7–year period, on the application of N fertilizers to Italian ryegrass for producing early spring grass, indicated that maximum yields are likely to be produced if the fertilizer is applied not later than the middle of March in most seasons. Only rarely did application in February result in a loss of N and in reduced herbage yields. Italian ryegrass appears to be able to make some growth at temperatures below 40†F.Increasing the rate of N application resulted in increased DM yield, the response averaging 9–4 lb DM per lb N. Herbage N concentration was increased by the additional N fertilizer. Nitro–chalk and ammonium sulphate were equally effective in producing early grass, irrespective of application date.

Notizen: The treatments in this summer–grazing experiment were designed as a 2 × 3 factorial, there being two levels of nitrogenous fertilizer (nitro–chalk), supplying 0 and 336kg of N/ha per annum (NO and N3, respectively) and three stocking rates. The fertilizer was applied in 7 dressings at approximately three–weekly intervals. The animals used were Hereford x Friesian steers; these were slaughtered at the end of the grazing season. The stocking rates were calculated on the basis of expected herbage production. The experiment was laid out in 6 randomized blocks which were grazed in rotation. Two blocks were cut for conservation before grazing each year; up to the end of June only 4 blocks were used for grazing.There was little contamination of the swards with unsown species. With the NO swards the clover contents declined each year, but remained fairly high at over 20% in 1965. Clover contents also declined each year in the N3 swards and by 1965 were only 2 to 4%.The quantities of herbage cut for conservation were higher from the swards receiving N. The live–weight gains of the cattle (per head) were higher at the lower stocking rates, the effect of stocking rate being more noticeable in the July to Oct. period. Live–weight gains per ha increased at the higher stocking rates. In 1963 and 1965, as stocking rates increased carcass weights per animal decreased and carcass quality, as indicated by the commercial grades, was poorer. In 1964, a dry spell from July to Oct. necessitated the removal of cattle from the experiment and the effects of treatment on carcass weight and quality were not apparent.

Notizen: Book reviewed in this article:BAKER, R. D., SPEDDING, A. W., KILKENNY, J. B. and TAYLER, J. C. An intensive system of beef production from grassland, using autumn-born calves from the dairy herd.M.A.F.F. At the farmer's service, 1967-8.M.A.F.F. Aspects of dairy economics, 1962-1965.DAVIES, WILLIAM. [The grasslands of Spain.]DIVISION OF PLANT INDUSTRY, CSIRO. Australian herbage plant register.

Notizen: Tall fescue and Italian ryegrass mixtures react differently to management in the year of sowing. The decrease in yield of tall fescue and the increase in growth of red clover, caused by the use of a cover crop, was still evident in the following year. In both the spring grazing and total yield of the first harvest year, the Italian ryegrass/ white clover mixture was better than the tall fescue/white clover mixture when a cover crop was used. The reverse trend was recorded when the grass plus clover was sown without the cereal. In general, the addition of red clover to the tall fescue/ white clover, or Italian ryegrass/white clover mixture, increased the yield, but the magnitude of the increase was modified by management during establishment. The increase in total herbage yield and the reduction of white clover growth due to nitrogen application were both related to management in the year of sowing. Consideration should thus be given to method of establishment in the assessment of herbage seeds mixtures.

Notizen: Germination results are presented for S48 timothy seed dried at air temperatures of from 75 to 135° after direct harvesting at 3 moisture levels, followed by cold-air conditioning for periods of from 1 to 3 days. The effect of conditioning was to increase the resistance of the seed to high drying-air temperatures, without producing any real improvement at low temperatures.The results for non-conditioned seed, published earlier, are converted to simple chart form giving the limits of initial moisture content and drying-air temperature for 90% germination. These charts can be used during the final drying of conditioned seed, provided that the original moisture content at harvest is within the “safe” range.

Notizen: The development and testing of a new silage additive consisting of sodium nitrite and hexamine (hexamethylenetetramine) are described. The investigation was conducted over 8 years and consisted of 15 separate experiments with small steel cylinders and 13 with plastic sacks. The former were carried out with freshly cut blue lucerne and a storage temperature of 25°. When a mixture of sodium nitrite and hexamine was applied at the rate of 0.4% of fresh herbage weight, the quality of the resulting silage was superior to that made with commercial additives marketed in Sweden and the losses were considerably reduced.

Notizen: Absorption by the tap-root and by different nodal roots of white clover S100 and translocation of 32P were investigated to find to what extent nodal roots can compensate for the absence of a tap-root. 32P absorbed from the tap-root was distributed evenly within the whole plant. When translocation from the 2nd and 7th nodal roots was studied, similar distribution was obtained only from the nodal root closer to the centre of the plant. The backward movement of 32P absorbed from nodal roots at the base of the plant increased as the root size increased. Removal of tap-roots resulted in temporary depression of translocation; its effect disappeared within 3 weeks.It is concluded that the ability of nodal roots to compensate for loss of the tap-root depends on their position and size.

Notizen: In a recent paper by Anslow it was concluded that there was no significant relationship between Leaf-area Index, light interception and growth rate in a perennial ryegrass sward. The author further concluded that higher growth rates would not be obtained by attention to this relationship. The data presented by Anslow are re-examined in this paper and the results of the analysis showed that: (a) recovery growth of the swards followed a sigmoid pattern of growth, (b) at low values of LAI growth rate was low and maximum growth rate was attained when most of the visible light was intercepted by leaves, and (c) the relationship between yield and LAI was linear, indicating that leaf-area increase after defoliation also followed a sigmoid pattern. These results are discussed in relation to Anslow's interpretation.

Notizen: An account is given of a method for measuring short-grazed pastures. The procedure has particular value in studying the relationship of animal performance to pasture availability. A number of other pasture characteristics may be measured concurrently. These include species composition, tiller number and mean weight, stem-base material, roots, rhizomes and plant litter. The influence of core size and shape is studied and variance components reported.

Notizen: Data from two field experiments, and from a root observation trench, suggest an annual cycle of root growth by grass swards. The production of adventitious roots from the tillers of four grass species, and from perennial ryegrass in a grass/clover sward varied greatly during the year. They were produced in increasing numbers through late winter to early spring; this rate fell sharply in April or May, and was low in summer. The differences in this annual cycle between grass species were small. Examination of roots of perennial ryegrass in a glass-sided trench showed that root elongation was most rapid in summer and was largely confined to the lower soil horizons. Rather more roots were produced in early autumn than during summer, but the rate of elongation was slow from October until spring.Individual roots of grasses appeared to survive for limited periods. Their longevity depended upon the time of year in which they were first formed; those produced in autumn or winter lived longer than those produced in spring or summer.

Notizen: The root growth of 3 temperate–region grasses (perennial ryegrass, Italian ryegrass, and cocksfoot) and of 3 tropical grasses (Dallis grass, Bahia grass, and Rhodes grass) was investigated in large glass–sided root–boxes. The trend of root numbers and the rate of elongation of roots were ascertained to discover how the Japanese climate affected the root growth of these species.All the temperate–region grasses produced new roots vigorously during spring, but root growth ceased in August, whereas the roots of tropical grasses grew rapidly in this month. The alternate use of these two types of grasses during the growing season may therefore be worthwhile in Japan

Notizen: A permanent pasture was ploughed, 5 rates of potassium were incorporated in the seed-bed and a timothy/white-clover seed mixture was sown direct without a companion crop. Plant counts were taken during the fourth week of establishment. The highest rate of potash increased the size and number of timothy/white-clover plants considerably, without altering the timothy/white-clover ratio. Half the plots were cut once during the seeding year and the other half twice. Increasing rates of K increased dry-matter yields, particularly on the plots cut 7 weeks after sowing. Botanical analysis in the following year showed that, under both cutting systems, increasing rates of K tended to increase the proportion of white clover and decrease that of unsown species.

Notizen: Book reviewed in this artilce:THRAN, P.; BROEKHUIZEN, S. Agro-ecological atlas of cereal growing in EuropeTHE READER'S DIGEST ASSOC. [Ed.] Complete atlas of the British IslesM. A.F. F. At the Farmer's service.

Notizen: Two experiments were conducted to study the effect on nutrient loss and feeding value of making hay by different means, using a barn-drier, a forage-harvester, a crimper and conventional tedding. Both forage-harvesting and crimping of the herbage significantly increased the rate of drying, compared with tedding alone. In Exp. 2 this effect enabled the crimped and forage-harvested hays to be baled for storage 3 days earlier than the tedded hay. The use of the forage-harvester significantly reduced the yield of herbage compared with conventional mowing. Nutrient losses from cutting until storage were highest for the forage-harvested hays, the loss of dry matter between cutting and storage in the forage-harvested hays being 39·9 and 19·3%, respectively, in Expt 1 and 2 with corresponding losses in the conventionally made hays of 7·1% and 9·3%. Crimping the hay resulted in higher nutrient losses than tedding. In Expt 2 there was a loss of dry matter of 17·5% in the conventionally made hay during an 18-week storage period, compared with 3·6% in barn-dried hay, 10·8% in forage-harvested hay and 8·8% in crimped hay.In Expt 2, in which digestibility determinations were made, conservation decreased the total digestible nutrients and starch equivalent in all treatments. The use of the barn-drier gave the most efficient conservation of total digestible nutrients, followed by the crimped, forage-harvested and conventional treatments in that order. The starch equivalent values of hays made from the same sward were 43·0 when barn-dried, 39·8 when crimped, 38·6 after forage-harvesting and 31·6 after tedding.

Notizen: Two different sizes of seed of a tetraploid and a diploid Italian ryegrass were sown in pure stands. Harvests were made at frequent intervals from 14 to 54 days after sowing, the root-and shoot-yields and numbers of leaves and tillers being recorded at each harvest. The results suggest that seed size per se has little influence on leaf- and tiller-numbers and that large seed increases yield potential only during the first few weeks of growth.

Notizen: In a survey in the West of Scotland, utilized-starch-equivalent (U. S.E.) outputs from the grassland of 67 farms, mainly dairy farms, and 9 hill-grazing units associated with them, were assessed by the farm-recording method. The limitations and possibilities of the method are discussed. The results obtained were above average, but the farms were a selected group. The wide range of U. S.E. outputs from farms of similar type indicates the scope for improvement on farms with low levels of output. The need for more surveys to clarify existing production levels on commercial farms is emphasized.

Notizen: Three experiments examine the effects of giving small supplements of flaked maize to steers on the digestibility and retention of nutrients from rations of grass silage, lucerne hay and fresh lucerne. The digestibility of the dry matter, crude fibre and crude protein of the silage ration was depressed by the successive additions of 1, 2 or 3 Ib flaked maize per day. There was a tendency for the steers to retain more nitrogen as the level of starch supplementation increased, in spite of a lowered crude-protein digestibility. The digestibilities of the constituents of lucerne hay and fresh lucerne were slightly increased by the addition of 2 and 4 Ib flaked maize per day. The reasons are discussed for the different effect of the supplemental starch on the digestibility of the crude fibre from grass silage and from fresh or cured lucerne. Attention is drawn to the increase in the retention of N following the supplementation of silage with starch.

Notizen: Seven species or varieties of grass, and a mixture of 3 of them, were sown in pure swards and treated with 4 levels of nitrogenous fertilizer (0,17·5, 35 and 70lb N per acre per cut). Each species, and the mixture, was also sown with white clover. The experiment was cut 4 or 5 times per year. The effect of fertilizer on the yield of each grass was compared with the effect of clover on the yield of the grass/clover swards. Mean annual yields showed an approximately linear response to N; there was a small but significant fall in response to the highest level of N. Response among the species ranged from 20 to 30 Ib of dry matter per Ib N applied for the intermediate level of fertilizer and from 14 to 23 Ib for the final increment of fertilizer.S37 cocksfoot, S48 timothy, S24 ryegrass, and a mixture of these grasses, were high yielding and responded well to fertilizer N; Irish ryegrass and Agrostis tenuis were less productive and gave poorer responses to N. S215 meadow fescue and S23 ryegrass were intermediate in yield and response.There were no significant differences between the annual yields of the 8 grass/clover mixtures; the yields of the grass and clover components of each mixture were inversely related. The effect of clover on the yield of the grass/clover mixtures was estimated to be equivalent to the effect of an annual application of 205 lb N per acre to Agrostis tenuis and 120 lb N to S48 timothy. The fluctuations in annual yields were greater with grass/ clover mixtures than with grass swards receiving N.The yields of grasses when sown with clover were in similar order to their yields when sown pure; but whereas the latter tended to fall from year to year, the yields of the grass components of mixtures (except Irish ryegrass) did not.

Notizen: The effects were studied of nitrogen and phosphorus fertilizers on the production of perennial ryegrass at high altitudes in Kenya. N had little influence on production during establishment but increased it markedly during the second and third years. The effect of P was less and was related to the amount of N applied. The response to applied N in terms of dry matter production, and the recovery of the N applied, compared favourably with data from trials elsewhere. It is apparent from the results that temperate grasses can be productive at high altitudes in Kenya and provide a considerable potential for pasture production.

Notizen: As a preliminary step in the development of improved bred varieties an examination has been made of the factors which contribute to the success or failure of white clover (Trifolium repens) in hill land reseeding. Severe restrictions are placed on clover performance and N fixation in many hill areas in Britain by the poor climate, the low pH and exchangeable base status of the soils and the low frequency of effective indigenous Rhizobium strains.Agronomic solutions to some of these problems exist, but experience in mid-Wales suggests the need for new bred varieties with improved adaptation to the prevailing conditions, particular attention being directed to the limitation of N fixation by low soil temperature.

Notizen: Seed shedding was studied in 50 clones each of S5I and S48 timothy during 1961–3. Some clones retained on average during 2 or 3 seasons from 80–90% of their maximum seed weight until 42 days after peak anthesis; this was up to 28% above the varietal mean. The results suggest that clones which retain their seed also produce high yields of seed and of dry matter; they can also be easily threshed.

Notizen: It has been found that the rate of herbage production from perennial grass swards, cut at a stage suitable for grazing, is lower in midsummer than in late spring. This occurs even with an abundant supply of water and fertilizer. The growth rate of green material was measured in swards differing in leaf area and light interception, Results did not suggest that higher growth rates could be obtained by attention to this relationship. Examination of the tiller population of grass swards showed that, in summer, herbage yields from cocksfoot and timothy were correlated with the average tiller size. This was not so in either of 2 varieties of perennial ryegrass. During May, June and July there were changes in the erectness of the swards as measured by the proportion of the crop which could be harvested with a mowing machine. This proportion was maximal when the highest rates of production of herbage were recorded. The importance is discussed of the change from a phase when mature tillers are forming inflorescences to one when herbage is derived from young, vegetative tillers formed in the same summer.

Notizen: Trials are described in which the intake of silage of varying length was determined. The results indicate that a higher voluntary dry-matter intake occurred as the length of the silage became progressively shorter, but this effect appeared to diminish when the silages were supplemented with concentrates. Data from one trial indicate that reducing the length of hay had no effect on voluntary intake when concentrates were fed.

Notizen: The effects of 4 levels of applied nitrogen, ranging from nil to a maximum of 417 lb N/ acre/annum, in all combinations with 3 frequencies of defoliation, ranging from 2 to a maximum of 10 cuts per annum, on herbage production from a perennial ryegrass/ timothy/meadow fescue/white clover sward were measured. These treatments were operative for 2J years, and in a subsequent year the residual effect of cutting frequency was tested. Dry-matter yields of total herbage and of the clover fraction are quoted, together with N yields of total herbage. Yield response to N was higher than in some other experiments in the U. K. Cutting frequency had a very large effect and, in general, the longer the interval between cuts, the higher was the dry-matter (though not the N) yield. There was a marked interaction between cutting frequency and level of N: at the high cutting frequency, dry-matter yield increased linearly with increasing level of N; at the medium frequency, response tended to fall off at the highest level of N; at the low frequency, yield declined with increasing level of N beyond 139 lb N per acre per anum.

Notizen: The effects of wilting and of various chemical additives on the digestibility and palatability of wet legume silages are reported. These silages showed most of the characteristics associated with the ensiling of wet herbage with a low content of soluble carbohydrate. Digestibility of all silages by wether lambs was low and exhibited little difference that might be attributed to the treatments. The untreated silage or the one sprayed with valeric/isovaleric acid, just before feeding, were more palatable to dairy heifers. Silage consumption was sharply reduced when urea was added during ensiling.

Notizen: Data are presented for the fourth (1979) and fifth (1980) harvest years of a trial in which four levels of N fertilizer (0, 30, 60 and 90 kg N ha−1) were applied each spring to swards with grass (perennial ryegrass cv. Barlenna) and each one of four cultivars of while clover (Blanca, Sabeda, Olwen and S100) or grass alone. Results from the first three years have been published.Dry matter (DM) harvested dropped from the fourth to fifth years over all swards by 1 −5 to 2 0 t ha−1 but response to N was maintained (17.4 and 24.4 kg DM (kgN)−l in response to 90 kg N ha−1 in 1979 and 1980 respectively) despite reductions in summer yields relative to unfertilized swards. Blanca swards produced significantly less DM harvested than all other cultivars in 1979 and all cultivars in 1980 except for Olwen. Clover DM harvested continued to fall from 1977, the mean for the unfertilized treatment in 1980 being 55% of that in 1979. Up to 1980 Sabeda swards produced more clover DM harvested than Blanca swards. Linear regressions between annual clover content at zero N and at each spring N level for each sward type over 5 harvest years were very highly significant. It is concluded that all cultivars used responded similarly to spring N. Further work to develop a method for predicting the effect of spring N on clover content of given swards is required.

Notizen: Preliminary experiments were conducted to assess the winter hardiness of representative cultivars or populations of Festuca rubra, Holcus lanatus and Agrostis spp. in comparison with a hardy (Premo) and a susceptible (Grasslands Ruanui) cultivar of Lolium perenne. Two controlled-environment tests and a field experiment including two cutting and two fertilizer managements are reported.Grasslands Ruanui andH lanatus suffered most damage in all tests. In the controlled-environment experiments, Premo was at least as hardy as the F. rubra and Agrostis cultivars but in the field Premo was more susceptible. Spring growth of Premo was affected more by the cutting and fertilizer managements applied the previous summer and autumn than was spring growth of F. rubra or Agrostis spp.It was concluded that, whereas use off. F. rubra or Agrostis spp. should not be limited by fears of winter damage, poor winter hardiness may limit the value of H. lanatus for hill and upland reseeding.

Notizen: Patterns of defoliation in perennial ryegrass-dominated swards were examined in two experiments. In Experiment I measurements were made on four swards after a single overnight grazing. In Experiment 2 observations were made repeatedly on marked tillers in two continuously stocked swards which were grazed down over a 24-d period. In both experiments the chance of defoliation was related to lamina height both within and between age classes. Lamina angle was measured in Experiment 2 and within age classes the chance of defoliation was also independent of lamina angle. In Experiment 1 tillers most frequently had both of the two youngest laminae grazed; in Experiment 2 tillers with only lamina 1 grazed occurred most frequently, but defoliation of the two youngest laminae was again common.The different frequencies of grazing of the different classes of laminae is interpreted as being a function of their frequency of occurrence within the grazed layer at the top of the sward. The pseudostem apparently restricted the depth of the grazed layer in the very short swards of Experiment 2.Grazing behaviour in relation to sward structure and the patterns of defoliation and their implications for herbage production are discussed.

Notizen: Perennial ryegrass and white clover were grown in boxes with either no competition, root competition only, shoot competition only, or both root and shoot competition between them, Boxes received either no nitrogen or 200 kg N ha−1 as a split application. The experiment was harvested at 8, 12, 16 and 20 weeks after sowing. Perennial ryegrass was more competitive than white clover throughout the experiment and its overall competitive ability increased with Lime. The effects of root competition were greater than those of shoot competition at the first harvest, with both forms of competition having similar affects at the second harvest, while at the third and final harvests shoot competition had greater effects than root competition. At the later harvests N application increased the overall competitive ability of perennial ryegrass, relative to white clover, mainly owing to the increase in its shoot competitive ability.

Notizen: Inflorescence-bearing tillers of Italian ryegrass (Lolium multiflorum cv. RvP) were dried in controlled temperature, relative humidity and air speed conditions chosen to be within the range likely to occur in a hay swath drying in the field. After drying for increasing intervals the tillers were separated into inflorescence, exposed flowering stem, leaf-laminae, leaf-sheath and flowering stem enclosed by leaf-sheath and the drying rates of these components in addition to that of whole tillers were measured. There were large differences in drying rate between components, but the differences were similar over the range of drying conditions employed. The drying rate of the inflorescence as well as that of stem enclosed by leaf-sheath was found to be very low and that of leaf-laminae and leaf-sheath very high.

Notizen: Book reviews in this article: Genetic Resources of Forage Plants Edited by J. G. McIvor and R. A. Bray Nutritional Limits to Animal Production from Pastures Edited by J. B. Hacker Herbivory. The Dynamics of Animal-Plant Interactions By Michael J. Crawley