ALBERT

Notes: Two comparisons between spring and autumn pasture for beef cattle were made. Animals used in all comparisons were of similar breed and weight and were subjected to the same feeding regime for 6–8 weeks before turn-out. The pastures were grazed on an equal grazing pressure basis between season comparisons. The pastures received similar rates of fertilizer N between seasons and had similar lengths of rest period for regrowth.Intakes of digestible OM were greater per unit of metabolic liveweight in spring than in autumn. Daily liveweight gains in spring were high, being 1·09 and 1·37 kg (2·4 lb and 3·0 lb), but were lower from autumn pasture at 0·98 and 0·71 kg (2·2 lb and 1·6 lb). Weather was implicated as a factor affecting daily gain from autumn pasture. Greater herbage yields in spring supported 42 and 204 more grazing days per ha which together with the greater gains per animal supported 80–120% more liveweight gain/ha.

Notes: The effect of artificial drying under commercial conditions on the digestibility and voluntary intake of herbage by sheep was studied, using either van den Broek (900°C inlet temperature) or Swiss Combi (1100°C inlet temperature) triple-pass drum-type driers. Organic-matter digestibility of chopped dried herbage was 8·3, 5·8 and 5·3% lower than that of fresh herbage in Experiments 1, 2 and 3, respectively. Packaging chopped dried grass into ‘cobs’ caused a further reduction in OM digestibility of up to 2·8%. Pre-milling plus packaging (i.e. ‘pelleting’) depressed OM digesti bility of chopped dried grass by 5 to 6 percentage units. Digestibility of dried grass in its various physical forms was further reduced when offered ad lib.; the greatest fall (9·4%) occurred with pellets and the smallest fall (0·8−1·3%) with loose chopped material; cobs were intermediate at 4·3−7·0%.

Notes: Two paddocks each received a total of 412 kg N/ha (371 lb/ac) between April and July in four equal applications. The paddocks were grazed four times for four days by two groups of 5 Friesian cows starting 14 and 21 days after each N applica tion.The nitrate-N content of the herbage DM reached a peak of 0·76 % in the third grazing 14 days after N application. There was a significant (P 〈 0·001) correlation (r =0·67) between water soluble carbohydrates and nitrate-N in the herbage DM.No marked changes occurred in eitber the methaemoglobin or packed cell volume of the blood samples from either group.No detrimental effects on animal health or production were recorded during the experiment.

Notes: An investigation into the effect of including dried grass in the supplement given to dairy cows at pasture is reported. Supplements containing 0, 50 and 100% dried grass were used in the investigation which was carried out in two parts. In the first part 12 high-yielding cows with unrestricted access to pasture were used in an experiment with a change over design to assess the effects of feeding 5 kg/day of each supplement on milk yield and composition. In the second part 8 steers, housed in stalls and given cut herbage from the same sward as that grazed hy the cows, were used in a change over experiment to assess the effects of the three supplements on herhage and total DM intake. No significant differences in milk yield between supplements were ohtained, the mean yields being 23·9, 24·5 and 23·9 kg/day for the supplements containing 0, 50 and 100% dried grass, respectively. Milk composition was also not significantly affected by including dried grass in the supplement. In the indoor feeding trial using the steers, the addition of 3·5 kg DM from the supplement resulted in an increase in total DM intake of only 1·3 kg/day. There was no significant difference hetween supplements on herbage and total DM intake.

Notes: A medium quality barn-dried hay and a poor quality field-cured hay were each supplemented with 3 levels of concentrate in the diet of young beef cattle, averaging 313 kg liveweight. The supplement was given on predetermined hay concentrate metabolizable energy (ME) ratios based on the determined ME of the hays and an assumed ME of 3·0 McalsAg DM for the supplement. The hay concentrate ratios used were 1:1, 1:2 and 1:3, the aim being to provide a reasonable rate of growth (0·7 kg/day) with the poorer hay. It was necessary to include urea in the concentrate mixtures used on the 1:1 and 1:2 ratios with the field-cured hay. The urea appeared to have an adverse effect on the intake and utilization of DM on the 1:1 ratio. The range of mean intakes of supplement DM was 3·02 to 4·41 kg/day for the barn-dried hay and 2·23 to 4·61 for the field-cured hay. Mean daily liveweight gains with the barn-dried hay were 0·76, 0·89 and 0·85 kg for the 1:1, 1:2 and 1:3 ratios, respectively, with no significant difference between ratios. The mean daily gains with the field-cured hay were 0·39, 0·77 and 0·75 for the three ratios, the mean gain on the 1:1 ratio being significantly lower than those of the other ratios. The ME conversion ratios were not significantly affected by either ratios or hay type, except on the 1:1 ratio with field-cured hay. There were significant differences between the barn-dried hay and field-cured hay diets in the digestibilities of DM, organic matter, crude protein and energy; the mean coefficients for DM being 74·5% and 65·6%, respectively.

Notes: Book reviewed in this article:GRIME, J. P.; LLOYD, P. S. An ecological atlas of grassland plants.KOWAL, J. M.; KNABE, D. T. An agroclimatological atlas of the Northern States of Nigeria with explanatory notes.HOYLE, B. S. (Editor) Spatial aspects of development.BRANSON, F. A.; GIFFORD, G. F.; OWEN, J. R. Rangeland hydrology.MILTHORPE, F. L.; MOORBY, J. An introduction to crop physiology.HEWITT, G. B.; HUDDLESTON, E. W.; LAVIGNE, R. J.; UECKERT, D. N.; WATTS, J. G. Rangeland entomology. Denver, Colorado, USA, Society for Range Management.BOR, N. L. The Grasses of Burma, Ceylon, India and Pakistan (excluding Bambuseae).PIRIE, N. W. (Editor) Leaf protein: its agronomy, preparation, quality and use.

Notes: Two clamps of maize silage were prepared in mid-October, one with 0·33% propionic acid applied during harvesting and one without additive. The treated silage had a peak temperature 3°C below that of the untreated silage. The estimated loss of DM during ensiling was 8% greater in the untreated silage. The stability and acceptability of the silages were tested after exposure to air. The treated silage was slightly more stable than the untreated milage and the intakes by heifers were sligbtly greater. The digestibilities of the two silages estimated in wether sheep were similar, averaging 68·6% digestible OM in the DM at maintenance level and 63·5% at a high level of feeding. The intakes and growth rates of calves and beifers oifered the two silages were also similar.

Notes: A series of 9 experiments carried out on an alluvial soil at two levels of fertility during the period 1971–3 showed that cultivation of the mineral soil was unnecessary for the satisfactory germination, emergence and establishment of a wide range of forage crops. With small-seeded crops (grasses and clover) non-cultivation gave improved establish ment and early growth compared with crops from soil which had been disturbed.A second series of 6 experiments investigated the effects of surface plant material on the establishment of a smaller range of forage crops sown without cultivation. The presence of this mat or trash was associated with a reduction in establishment of seedlings, but not with subsequent growth of the plants that became established. Treatments which processed or partially removed the organic matter were associated with increased emergence. Crops with small seeds were more susceptible to the effects of organic matter than those with larger seeds.

Notes: Variations in soil-water and plant-water status were examined in swards of perennial ryegrass over a period of 2 years. Unirrigatcd swards were compared with swards partially irrigated after cutting and with swards fully irrigated after cutting and then again whenever a 25 mm potential soil water deficit (SWD) arose. Two levels of N were applied to the swards (Nj= 250 kg N/ha, NT= 500 kg N/ha in each year). Frequent measurement of the water in the soil profiles beneath these swards with a neutron soil-moisture probe, enabled comparisons to be made of the actual SWD with the potential SWD on which the irrigation regimes were based. In the unirrigated swards the actual rate of water use by the swards fell below the potential rate of use at a potential SWD of approximately 50 mm. On the other hand, frequent irrigation at a potential SWD of 25 mm often failed to maintain the actual deficit within 25 mm of field capacity. Under both the unirrigated and the partially irrigated swards, greater use was made of the soil water below 30 cm depth in the N2 treatment than in the N1.The pressure-chamber technique proved particu larly suitable for measuring the variation in leaf-water potential (LWP) of grasses in the field. LWP was highest (least negative) at dawn and, provided that no dew was present on the leaves, was related to the actual SWD. There was no direct relationship between the daily minimum value of LWP and SWD, the former being determined largely by evaporative demand. However, LWP in frequently irrigated swards rarely fell below –15 atm, whereas much lower values were recorded in swards on drier soils. It is suggested that the effect of irrigation on plant-water stress may be most readily assessed from the LWP at dawn.

Notes: Book reviewed in this article:GETHING, P, A.; NEWBOULD, P.; PATTERSON, J. B. E. (Editors) Hill pasture improvement and its economic utilisation.BELL, H. M. Rangeland management for livestock production. Norman, Oklahoma, USA, University of Oklahoma Press.FISCHER, W.; LÜKE-ENTRUP, E. (The most important grasses. Their importance in agriculture, lawns and landscaping.)CLARKE, E, G. C; CLARKE, M. L, (Revisers) Garner's veterinary toxicology. London, UK, Bailliére Tindall & Cassell.HEISER, C. B., Jr, Seed to civilization. The story of man's food. San Erancisco, California, USABUTLER, G. W.; BAILEY, R. W. (Editors) Chemistry and biochemistry of herbage. Volume 3. London, UK, Academic Press Inc.YOUNGNER, V. B.; McKELL, C. M. (Editors) The biology and utilization of grasses.HODDER, B. W. Economic development in the tropics. London, UK, Methuen & Co. Ltd.GEUS, J. G. DE Fertilizer guide for the tropics and subtropics.

Notes: An experiment is described in which 10 cutting treatments were applied to plots of perennial ryegrass. In 4 treatments the swards were cut uniformly using one of the following regimes: cut to 15 cm every 2 weeks (regime hf); cut to 15 cm every 6 weeks (hi); cut to 5 cm every 2 weeks (If); cut to 5 cm every 6 weeks (li). In the remaining 6 treatments, each plot was cut in alternate 9 cm strips using combinations of two of the above regimes; hf/hi, hf/lf, hf/li, hi/If, hi/li, and If/li. The non-uniform cutting in the latter 6 treatments resulted in a micro-pattern of height and/or frequency of defoliation.DM yield from the best non-uniform cutting method (If/li) was as great as that from the best uniform method (li). This was due to an increased yield from areas under regime If when adjacent to areas under li, compared with uniform defoliation under regime If. Results for other treatments also showed that the yield from an area can be influenced by the defoliation regime applied to adjacent areas. The trend was for yield to be greatest if adjacent areas were cut high (as opposed to low) or frequently (as opposed to infrequently). There was less bare ground and more perennial ryegrass and weeds at the end of the experiment in areas previously adjacent to frequent (0 as opposed to infrequent (i) cutting regimes.To assist in the interpretation of field results, an experiment was carried out in which uniform and non-uniform cutting treatments were applied to individual plants of perennial ryegrass growing in pots of soil in a glasshouse. There was some evidence of an interaction between the growth of high and low parts of plants cut non-uniformly. There is a discussion of the possibility of devising new ways of harvesting grass by cutting. It is suggested that the non-uniform grazing pattern of livestock may not be wasteful.

Notes: A power-driven corer, designed to collect internally samples cored from small plot forage cuts of about 5–15 kg, is described. Sampling errors for percentage DM are shown to be lower than those associated with conventional practices; smaller than usual sample weights (200 g) which are less demanding on oven space are shown to be feasible, and the tedium of the sampling procedure is alleviated.

Notes: Shoot dry weight, leaf area, leaf lamina dry weight and N-fixation of L. uliginosus cv. Grasslands 4705 were compared with those of T. repens S184 over a 90-day period frotn sowing, in pots in a greenhouse. Three P and three pH levels were imposed and there were three destructive harvests at 30-day intervals. N-fixation was estimated by the acetylene reduction technique prior to the last harvest. L. uliginosus had higjier means than T. repens for all characters measured under all treatments at all harvests. Large increases in shoot weight and leaf area were associated with addition of P, particularly with the first increment of P to L. uliginosus. High P reduced the contribution of lamina to total shoot weight in T. repens more than in L. uliginosus at the second harvest. Raising pH increased shoot weight and leaf area in both species.N-fixation was low in both species at low pH and low P. This was increased by addition of P, a smaller quantity being necessary for the same response in L. uliginosus compared with T. repens. At the higher P levels, the high pH gave rise to lower N-fixation than at the medium pH.Results are discussed in relation to field trials of other workers and the possible suitability of L. uliginosus for low fertility upland conditions.

Notes: Groups of six-month old lambs, which were either experienced or inexperienced grazers, strip-grazed swards of S24 perennial ryegrass or Hungaropoly tetraploid red clover, at daily herbage allowances of 20 or 40 g OM/kg LW, in late August and September. The swards were similar in N content, but the weight of standing crop, and its digestibility, were higher on grass than on clover. Estimates of herbage intake were made in two successive periods of 19 days. Intake (g OM/kg LW) was lower at low than at high allowance (by 22% and 28% in periods I and II). and experienced grazers ate more than inexperienced animals (by 27% and 22%). Intakes on clover were 28% higher than on grass in Period I, but in Period II the difference was not significant.

Notes: Liveweight and wool production data are presented from a grazing management experiment in which continuous stocking was compared with a four-paddock rotational system at three stocking rates on a sown pasture. Significant differences were recorded in liveweight and wool production between stocking rates. The overall effect of management was non-significant but its interaction with stocking rate and year were both significant.At the intermediate stocking rate (8 wethers/ac, 20 wethers/ha) increases in both liveweight and wool production were recorded for the rotational management system; in this treatment there was also less need for supplementary feeding. Greater wool production was recorded from the continuously grazed treatments at both the high and the low stocking rates but there was little effect on liveweight or the need for supplementary feeding.

Notes: Book reviewed in this article:HUMPHREYS, L. R. Tropical pasture seed production.

Notes: Observations were made on urine scorch on pastures at North Wyke. Scorch was caused by cattle and by sheep and occurred sporadically throughout the grazing season in wet and in dry weather, but not all urinations caused scorch. Where ryegrass was completely killed, subsequent colonization was by weed speeies. A relationship was found between extent of scorch and grass N content and the scorching effect appeared to be on the root system of the grass and not on the foliage.

Notes: A trial was carried out to find management practices which would permit the best discrimination for winter performance of erennial ryegrass cultivars. Due to the mild winter experienced only a few of the plants were killed outright. The cultivars were therefore assessed for percentage of green herbage and for spring growth.There were four sites: an upland and lowland site at Aberystwyth and one site each at Edinburgh and Cambridge. At all sites two N rates (totals of 125 or 550 kg/ha in the first year after sowing) and 5 autumn cutting treatments were used to give differences in the amounts of herbage remaining at the onset of winter. The last dates of defoliation in the autumn were: C1 end of August; C2 end of September; C3 end of October; C4 mid-November; C5 was cut on all these dates. Four cultivars (Grasslands Ruanui, S321, Premo and Argo) which differed in their autumn growth potential, frost susceptibility and degree of winter dormancy were grown.The autumn yield of S321 was, in general, higher than that of the other cultivars but there were interactions with N, management and location. The data on percentage of herbage remaining green in February illustrated differences due to the siting of the trial. In the conditions prevailing the two Aberystwyth sites facilitated greater discrimination between cultivars than those at Edinburgh and Cambridge.In three of the four sites the management which produced most winter ‘burn’(including both that due to natural senescence and that due to winter damage) involved accumulation of herbage in the autumn but there were considerable sites × managements interactions. For example at Cambridge management produced no significant effect whereas at the Aberystwyth lowland site frequent defoliation in the autumn had more effect than allowing herbage to remain uncut after the end of August. High N significantly decreased the percentage of green herbage only at the two Aberystwyth sites.Over five-fold differences in spring yield were obtained, the heaviest yields being recorded at Edinburgh and Cambridge. However, there were large interactions between environments and cultivars; for example the higher N rate reduced spring yield at Aberystwyth but increased spring yield at Edinburgh and Cambridge. Premo and S321 had similar yields in spring at the Aberystwyth lowland and Cambridge sites but Premo was higher yielding than S321 at the Aberystwyth upland site and at Edinburgh.The large environmental effects and their interactions with cultivars illustrate the difficulties of cultivar assessment and the dangers inherent in national recommendations for grass cultivars.

Notes: Four levels of nitrogen, 188, 285, 358 and 392 kgJ.ha (150, 225, 285 and 350 units/ac) supplied as anhydrous ammonia were injected on each of four occasions, 18 Dec, 5 Feb., 12 Mar. and 16 Apr. DM and CP yields were estimated at each of three harvests taken on 4 June, 19 July and 28 SeptTotal DM yields showed only a 10% difference between the highest yielding injection date, 12 Mar., which yielded 12270 kg/ha (10946 Ib/ac) and the lowest, 16 Apr., which yielded 11169 kgJ.ha (9963 Ib/ac). Early injection of ammonia promoted growth during the late spring and later injections resulted in increased yields at the two later harvests. The responses per kg fertilizer N were 11.9 kg DM (10.8 lb/unit) and 3.6 kg CP (3–3 Ib/unit). It was concluded that ammonia should be applied to grassland before April and, preferably, during March, for maximum yields of DM and CP.

Notes: Cutting patterns producing high and low areas were imposed on swards of Dactylis glomerata and Lolium perenne to test whether output could be increased when compared with traditional uniform cutting methods. In two experiments, swards of both grasses were divided into parallel 9 cm strips which were cut alternately on different occasions to a height of 5 cm. These swards yielded a similar quantity of herbage DM to that from other swards cut uniformly at the same height and frequency. In a third experiment, swards of Lolium perenne were divided into alternate strips of unequal width (9 and 4.5 cm). The narrow strips were allowed to grow to a height of 15 cm and were occasionally trimmed at this height. The wide strips were cut to 5 cm at 2–or 4–weekly intervals. Areas cut to 5 cm every 2 weeks yielded significantly more DM when adjacent to high areas than when adjacent to areas cut to 5 cm every 2 weeks (i.e. under uniform cutting). The interaction between adjacent areas having different defoliation regimes is discussed in relation to the possibility of obtaining some additional output from a suitable no niform cutting system compared with uniform cutting. Sward productivity under no niform grazing patterns of livestock is also discussed.

Notes: Ten Certified Seed lots of S23 perennial ryegrass produced in different counties in England during 1966, and ten lots produced in 1972, were examined for differences in characters affecting seed quality. The 1966 seed lots differed significantly in 1000–seed weight, germination rate, N content of the seed and seedling dry weight, and there was a significant correlation between seed N content and the seedling weight of the progeny.In both S23 and S24 perennial ryegrass N applied at inflorescence emergence or at anthesis increased N content of the seed and seedling dry weight. In S24 application of N at anthesis increased 1000–seed weight also. When plants of S23 perennial ryegrass were subjected to reduced moisture supplies their seed N content was increased. It is concluded that late N applications to grass seed crops may affect seed quality.

Notes: A reassessment of the potential productivity of 37 varieties of red eiover suggests that DM productivity is equivalent to grass given fertilizer N at 252 kg/ha for the 1st year, 209 kg/ha for 2nd year and 144 kg/ha for 3rd year of production. Corresponding equivalents for CP productivity of the red clover swards were 298, 228 and 206 kg N/ha. Varietal differences in productivity were significant Average yields of total herbage DM in the 1st, 2nd and 3rd harvesting years were 10.9, 8.7 and 8.2 t/ha, containing 6.5, 5.9 and 6.0 t/ha red clover, respectively. For two harvesting years, the most productive varieties were Essi, Kuhn, Hungaropoly, Robina, Tilo Daehnfeldt, Redhead and Corona Otofte. Rea 4N and a few other tetraploid varieties were very productive in the 3rd year. Hungaropoly, although showing a decline in the 3rd year, was the most productive over 3 years, with an average yield of 11.5 t/ha per year total herbage DM containing 10.2 t/ha per year red clover DM.Such high potential DM production warrants further investigation into the persistence of red clover, its conservation and the problems of its utilization by livestock.

Notes: The bacterial decomposition of grass fructosans with different degrees of polymerization was monitored in vitro. The period required for the microbial decomposition of polymeric fructosans was directly related to the extent of polymerization. It was concluded that there might be a relationship between the digestibility of other organic nutrients of fodder plants and polymerization and that polymerization increases with maturity of the plant.

Notes: Grass silage made in late May from S23 perennial ryegrass was offered to 14 Ayrshire cows in a 16–week winter-feeding experiment. The silage had a DM content of 23.2% and contained 16–8% CP and 70.4% digestible organic matter in the DM. The silage was fed ad lib. as the sole feed in the control treatment, and supplemented with either barley or higuality dried grass cubes at the rate of 2, 3 and 4 kg/10 kg milk (2, 3 and 4 Ib/gal) in the other 6 treatments. The daily intake of silage DM was 11.6 kg/cow (25.6 lb) in the control, and significantly less in the supplement treatments. Silage intakes were higher in the dried grass than in the barley treatments. The mean daily yields of milk were 14.5 kg.cow (32.0 lb) in the control, 15.7, 16.6 and 17.0 kg (34.6.36.6 and 37.5 lb) in the barley treatments, and 17.8, 20.2 and 19.8 kg (39.2, 44.5 and 43.6 lb) in the drierass treatments, at the 2, 3 and 4 kg rates of feeding, respectively. The solidoat (SNF) content of the milk was lowest in the control treatment and highest in the drierass treatments. It is concluded that grass silage of high digestibility could be made successfully on a farm scale and that, with such a silage, a supplement of higuality dried grass was superior to a supplement of barley for milk production.

Notes: The effect of intravenous supplements of L-methionine on the voluntary intake of a ryegrass silage, prepared using formic acid as an additive, was determined in a 4×4 Latin Square experiment with 4 sheep. Animals receiving no methionine consumed 1061 g DM/day; those receiving 0.8, 1.2 and 2.0 g methionine/day consumed 1015, 1012 and 1078 g DM/day. The concentration of methionine in blood plasma (Y; (imoles/I) increased with the dose rate of methionine infused (X; g/day) such that Y=36.7 + 38.3X (r=0.80; P〈0.001). It is concluded that with a diet of this type methionine may be limiting for protein synthesis in the tissues but is not involved in the control of food intake.

Notes: Extras samples were collected from ocsophageally fistulated sheep that had been fed mixtures of known proportions of a legume and a grass. The botanical composition of these samples was estimated by two microscope point techniques. When estimates were made by recording hits on each species the legume content of the ingesta was consistently underestimated by up to 23%. Much of this underestimate was attributed to the weight per unit area of the leaves of the legume being approximately twice that of the grass leaves. When the microscope hits were adjusted for the weight per unit area of each of the plant components (leaves, petioles, flowers and seed pods) the relationship between the estimated and actual legume consumed was improved, the greatest difference between actual and estimated legume being approximately 5%.

Notes: In an experiment, described earlier (19) to study the regrowth of Italian ryegrass following a cut in late April, the N and nitrate-N content of herbage at 3 levels of applied N followed a similar pattern to that noted in earlier years in Cambridge. N content, however, did not fall to such a low level as in Cambridge. N yield fell later and less quickly than in Cambridge. The application of a very high level of N, 175 lb/ac (196 kg/ha), raised N and nitrate-N content and yield from the second or third week onwards. Changes with time in P and K content and yield were broadly similar to those for N. Level of N had only a small effect on content of P and K. Following the period of increase in yield of N, P and K, there was a period of about 6 weeks of relatively constant yield, followed by a fall. The content of N, P and K in fresh, rather than dry, herbage changed little with time from the fourth to the fourteenth week, despite major changes in crop maturity. The ratio P: K was little affected by level of N or time of harvest.

Notes: A New Zealand selection of marsh birdsfoot trefoil proved more productive than white clover when oversown on wet upland pasture in the west of Scotland and exposed to close grazing during 1966–70. A number of introductions were assessed simultaneously at lowland and upland sites as spaced aggregate clumps in 1970–71 and showed variations in growth habit and time of flowering. These collections out-yielded clover control varieties at the upland site during both harvest years, Chilean material being the most promising in terms of DM yield and recovery after defoliation.Three New Zealand selections were compared with local material in two new experiments sown on the same day at the same sites and in a spaced-clump experiment at the upland site. Establishment was adversely affected by prolonged dry weather after sowing, but at the lowland site, probably aided by the germination of hard seed, the plants developed sufficiently to allow DM yields to be determined. The induced tetraploid variety Grasslands Maku was high in seedling vigour and subsequently yielded well at both trial sites, whereas normal diploid varieties established less rapidly, yet produced similar DM yields in the second harvest year. The species clearly shows promise as an oversown legume for improving livestock feed in wet upland pastures.

Notes: Book reviewed in this article:DABADGHAO, P. M.; SHANKARNARAYAN, K. A. The grass cover of India.SPRAGUE, H. B (Editor) Grasslands of the United States.NIX, J. Farm management pocketbook. Ashford, Kent, UK; Wye College.HANF, M. Weeds and their seedlings.CLAYTON, W. D.; PHILLIPS, S. M.; RENVOIZE, S. A. Flora of Tropical East Africa.DYKE, G. V. Comparative experiments with field crops.MOULE, C. [Special plant techniques. 1. Fodders.] Phytotechnie speciale.DUFFEY, E.; MORRIS, M. G.; SHEAIL, J.; WARD, L. K.; WELLS, D. A.; WELLS, T. C. E. Grassland ecology and wildlife management.COX, S. W. R.; FILBY, D. E. Instrumentation in agriculture.HOGG, W. E. (Editor) Irrigation.

Notes: The main objectives of research and development In haymaking are to minimize dependence on weather and to reduce loss of nutrients. Treatment of a cut crop, especially by mechanical conditioning, shortens drying time substantially while the use of chemical desiccants before or after cutting may also increase the drying rate.The advantages of terminating field exposure before drying has been completed are particularly important. Barn drying from about 40% moisture content (m.c.) wet basis has given good results. A useful alternative might be the application of preservatives to hay of high moisture content. The suppression of harmful spores, whether through barn drying or preservative treatment, lessens the risks to human and animal health.

Notes: Fifty-four grass, legume and whole-crop maize forages were frozen and fed to sheep in amounts calculated to meet their daily DOM requirements for maintenance. The mean level of feeding achieved was 1·01±0·014 ± maintenance, and the mean and median values of the standard error of means of the coefficients of apparent DM digestibility determined were 0·66 and 0·50 percentage units. The range in composition of the forages was: cell walls 25·0– 64·2, digested cell walls 15·1–50·0, and apparently digested organic matter 56·4 to 76·1 g/100 g DM. The proportion of the DOM arising from cell walls had an even greater range (22–72%) and differed markedly between the forage species in mean value and in respect of the trend with advancing maturity. It was concluded that the conduct of the digestion trials and the range in composition of the forage samples examined were adequate to provide samples of herhage suitable for the comparison of laboratory procedures of forage evaluation.

Notes: The results of three sample surveys of grassland, carried out in England in 1939, 1947 and 1959, are reported. In 1939, the amount of agricultural land returned as permanent grass was at a record level. Nearly half of this was ploughed up during the Second World War. This was primarily for tillage crops, but the secondary aim was for old grass to be replaced by sown swards of better quality. The surveys showed that, during the 20-year period, the quality of English grassland improved (a) because a greater proportion of the poorer swards was ploughed; (b) because greater use resulted in improvements in the botanical composition of the remaining old grass, and (c) because of the large increase in the use of sown grass in both arable and non-arable farmings.

Notes: Foliar application of CUSO4 to mature grass to increase the Cu content of the hay crop was markedly affected by rainfall within 24 h of the time of application. The mean Cu concentration of hay treated with 5·6 and 11·2 kg CuSO4/ha was 100 and 208 ppm, respectively, when no rainfall occurred during this period, but only 24 and 41 ppm when rain fell within 24 h. Rain 4 or 5 days after spray application had no effect on the ultimate Cu concentration of the hay. It is suggested that sheep could safely graze the aftermath as, with one exception, concentrations of Cu found were only from 11·4 to 20·6 ppm. l±l kg CuSO4/ha applied in dry conditions was sufficient to raise Cu concentrations in hay to levels which should preclude the occurrence of Cu deficiency when fed to cattle in winter. Reductions in hay yield following CUSO4 applications in dry weather suggest a need to examine the use of more dilute sprays, or other means for increasing the Cu content of hay.

Notes: Ten cultivars of Italian ryegrass (Loliumultiflorum) were assessed over two seasons under a cutting regime and a cattle grazing system. A high correlation between the two managements was obtained in respect of annual production, the ranking order of yield being similar in each case for the range of cultivars. Persistence under grazing was highly correlated to that under cutting when assessed at the end of the experiment. There was, however, some evidence of interaction between the two systems in the performanee of one cultivar. The results are discussed in the context of herbage cultivar evaluation for the purpose of recommending those most suitable for general use.

Notes: This paper describes the regrowth of Italian ryegrass, following a cut in late April, measured by recording DM yields at weekly intervals up to 14 weeks. There were 4 levels of applied N: 25, 75, 125 and 175 Ib/ac (28, 84, 140 and 196 kg/ha). Rate of growth up to 10 weeks was compared with that recorded in similar experiments in Cambridge in earlier years and was found to be generally similar. The highest yields of DM and digestible organic matter were recorded after 11 weeks; beyond this stage there was a fall in yield. There was a large response to 75 Ib N compared with 25, a moderate response to 125 Ib compared with 75 (greater during the last 7 weeks than during the first 7 weeks), and little response to 175 Ib compared with 125. The time-saving value of N is noted. DM content was appreciably lower than in Cambridge, apparently because of both surface and internal moisture, but showed similar trends. In some of the early weeks, especially at high N, the crop appeared to be supplying water well in excess of livestock needs. In vitro digestibility was much affected by stage of growth and little affected by level of N.

Notes: This paper considers the sequence of seed development by measurement and observation of ehanges in seed moisture content, weight, colour, endosperm consistency, germination capacity and yield in perennial ryegrass Grasslands Ruanui, timothy Grasslands Kahu and a New Zealand strain of prairie grass (Bromus unioloides).Seed moisture content was high (60–70%) after anthesis and declined at different rates, depending on the species and the weather. Maximum seed dry weight (maturity) was reached approximately 30 days after peak anthesis in all species and was influenced by N application and grazing. Colour changes in the seedhead and endosperm solidification proved unsatisfactory as measures of maturity. Endosperm solidification was reached 4, 11 and 12 days before maximum seed dry weight in ryegrass, timothy and prairie grass, respectively.Seeds removed from the plant as little as 7, 10 and 4 days after anthesis in ryegrass, timothy, and prairie grass, respectively, germinated, provided that dormancy was broken; but they did not retain viability after 3 months storage. Maximum viability of ryegrass, timothy and prairie grass seed tested immediately after harvest occurred 30, 38 and 16 days after anthesis, compared with 17, 35 and 12 days, respeetively, when germination testing was delayed for 3 months.In ryegrass, grazing caused a significant increase in seed yield in the second year while N application alone did not significantly increase yield. In timothy, grazing and to a lesser extent N, were both detrimental to seed yield in the second year. Highest yields were obtained in treatments not receiving either grazing or N. In prairie grass, grazing depressed and N application increased yields in both years. In all species similar or increased yield could be obtained by mowing the crop at, or slightly prior to, seed maturity and allowing seed development and ripening to continue on the cut straw for up to 10 days. Using this technique higher seed yields were obtained in ryegrass and timothy than when seed was direct-harvested. In prairie grass similar yields were obtained whether the erop was direct-harvested or threshed following drying in the swath for 10 days.The use of ‘drying curves’ for the prediction of correct cutting time of seed crops is suggested for ryegrass, timothy and prairie grass.

Notes: Forage diets were prepared from ryegrass (non oestrogenic control) and from red clover as pellets or as unwilted silage. Each diet was fed to separate groups of 20 Border Leicester × Cheviot ewes for three weeks prior to the introduction of the ram, and for two cycles after mating. Subsequently, all three groups of ewes were fed in a similar manner until lambing and the reproductive performance of the ewes was measured. The control diet was prepared by barn drying a primary growth crop of perennial ryegrass, Lolium perenne cv S23. Tetraploid red clover, Trifolium pratense cv. Hungarpoly, was harvested as a first regrowth crop and the pelleted diet prepared by high temperature drying, grinding (2 mm screen) and pelleting. The silage was prepared without wilting. The level of formononetin in the red-clover silage was three times that in the dried red-clover pellets.Compared with the control grass diet, the feeding of red clover in either form significantly reduced (P〈0·001) the number of lambs born. The incidence of barrenness was higher (P〈0·001) for ewes fed red-clover silage compared with red-clover pellets and the control diet. The rate of twinning was significantly (P〈0·001) higher for the ewes fed the control grass diet than for either of the red-clover diets. The resultant lambing percentages were 190,165, and 100% for the control grass, red-clover pellet and red-clover silage treatments. In flock management, both the grazing of red clover and the feeding of red-clover pellets or silage, prior to and during mating, should be avoided.

Notes: A technique for the automatic recording of the grazing behaviour of dairy cows was investigated, using ‘Vibracorders’ which transmit grazing movement via a pendulum and stylus to a 24 h recording chart. The total labour input was 2 h/day for 6 cows, which gave 144 h of results. In 2 months, 3312 h of recording were obtained. Total grazing time per cow in 24 h was 559 min. on a rigid rotational system of grazing and 638 min. on a system of set stocking. Grazing time was significantly and negatively related to the yield of available herbage DM. It is concluded that if the Vibracorders are sealed and fitted correctly, they are simple, reliable and accurate instruments for automatically measuring the grazing behaviour of dairy cows.

Notes: Animal production from intensively managed pasture (240 units N/ac or 300 kg N/ha applied annually) should in theory reach 11,000 Ib/ac (12,500 kg/ha) of milk or 1550 lb/ac (1750 kg/ha) of liveweight gain per year. The figure for theoretical milk production is achieved in experiments, although rarely approached in commercial practice; the figure for liveweight gain is never approached, either experimentally or commercially. On commereial farms in Britain, the average stocking rate for grazed lowland pasture in 1971 was about 0·74 cow equivalents/ac (l±82/ha), compared with a theoretical target of 1·9/ac; in 1969 fertilizer N application was about 48 units/ae (60 kg/ha). The main purpose of this paper is to suggest reasons for the differences between practical, experimental and theoretical levels of production.Economic factors may deter farmers from intensifying their grassland management, but the deterrent to high stocking rates may be the fear of running out of grass. In practice, ungrazed herbage is used as a buffer, but other feeds might be used for this purpose. Concentrates, pelleted roughages and even long dried grass and silage are too attractive to grazing beef cattle to be offered to appetite; but silage might be used as a long-term buffer. Fouling of pasture reduces efficiency of harvesting, but attempts to overcome this effect, by conditioning of grazing animals, spreading excreta or by alternation of grazing and cutting, have largely been unsuccessful.High production per unit area cannot be achieved without high production per animal. Legumes have often been found to increase production per animal, and a technique has been developed for growing red-clover and grass in adjoining areas and grazing them together. The clover was grazed satisfactorily by dairy cows (and caused no bloat) but failed to increase milk yield per animal.Recent calorimetric studies of grass have shown that the net energy value of digestible organic matter is variable, and in particular is low for late-season herbage.

Notes: In two 20-week grazing experiments, a rigid rotational system of grazing termed the ‘Wye College’ system was compared with a flexible paddock-grazing system in 1972 and with strip grazing and set-stocking in 1973. Eight spring calved Ayrshire cows were used on each treatment at a stocking rate of 5 cows/ha (2 cows/ac). The mean daily milk yields per cow were 17·7 and 17·0 kg(39·0 and 37·5 Ib) on the Wye College and the paddock systems, respectively, in 1972; and 17·9, 17·7 and 16·4 kg (39·4, 38·9 and 36·2 Ib) on the Wye College, strip, and set-stocking systems in 1973. The average annual output of milk varied from 11,500 kg/ha (1030 gal/ac) on the set-stocking system to 12,500 kg ha (1120 gal/ac) on the Wye College system, but none of the differences was significant. The most rapid decline in daily milk yield occurred on the set-stocking system in August and September as the amount of available herbage declined. This system requires further investigation. It is concluded that the Wye College system, with its rigid and pre-determined grazing cycle was as effective as either a one-day paddock or a daily strip-grazing system in producing high yields of milk.

Notes: The leaves of tropical grasses are eaten in larger quantities than stems of similar DM digestibility. To determine whether the same fact applied to a temperate grass, studies were made with leaf and stem fractions of Lolium perenne. The leaves of L. perenne had a 20% higher voluntary intake than the stems, white the DM digestibilities were only slightly higher (67·3%ν. 64·8%). The leaves also had a larger surface area/g, a higher initial (12 h) fermentation rate in vitro, larger content of pepsin-soluble DM, and a smaller energy require ment to grind I g DM in a laboratory mill compared with the stems.The difference in voluntary intake between the leaves and stems of L. perenne was smaller than that for a number of tropical grasses.

Notes: The botanical composition of extrusa collected from oesophageally fistulated sheep fed diets of known proportions of a legume and a grass was estimated by manual separation and a microscope point technique. The microscope hits were adjusted for the weight per unit area of each plant component in order to estimate composition by weight. The microscope point technique was more accurate than manual separation. The deviations between the actual lucerne percentages and percentages estimated by manual separation were explained by higher losses of organic matter prior to separation from the legume than the grass and by the presence of unidentifiable particles that resulted in only a portion of the samples being separated. After adjustments for these sources of error the estimates determined by manual separation were similar to the actual botanical composition of the ingesta.

Notes: Ear emergence data for 9 cultivars of perennial ryegrass have been recorded in Northern Ireland at the Plant Testing Station, Crossnacreevy, each year since 1967. These data show that while early spring (March-April) temperatures have a marked effect on the heading of early cultivars such as Gremie and Aberystwyth S24, the behaviour of later cultivars is more directly affected by temperatures at the time of their stem internode elongation. Ear emergence dates of late cultivars bear no fixed relationship to those of early cultivars.It is concluded that while records of early spring temperatures can be used to predict, with reasonable accuracy, the heading dates of early cultivars, such records do not provide a reliable basis for the prediction of heading dates of later cultivars. In Northern Ireland, reliable prediction of cutting dates for later cultivars to obtain herbage of a required level of digestibility is only possible on a short-term (one-two week) basis. Such predictions must take account of growing conditions in each individual year.