bluuebunny/crossref_metadata_2025 huggingface dataset:
The intake and performance of cattle grazing irrigated pastures. 1. Estimation of the digestibility of the pasture
Authors: Hennessy DW , Ahern CE
Published: March 2005

Faecal nitrogen-digestibility relationships were estimated for steers fed different fractions of an ungrazed irrigated pasture cut at two heights. The regressions of the fractions were then compared to that of the whole pasture. No significant differences were detected between the regressions of digestibility on log faecal nitrogen concentration, nor were there significant within-period regressions for the pooled treatments. On this basis it was suggested a single-sward regression would provide suitable predictions of digestibility of an irrigated pasture being grazed at different heights.
Low volume concentrate spraying for the control of the field cricket (Teleogryllus commodus)
Authors: Birks PR
Published: March 2005

The field cricket, Teleogryllus commodus (Walker) is an important pest of black cracking soils of south-eastern mainland Australia and of New Zealand. Insecticidal control was unsatisfactory until dieldrin was introduced. Residue problems associated with the use of dieldrin on pastures led to a revival of investigations into alternative treatments. The low volume concentrate application of technical malathion by aircraft gave rapid and effective control when applied late in the season. As little as 6.5 fl oz of 96 per cent malathion, estimated to cost no more than $1.20 an acre, including application costs, reduced cricket populations by 94-95 per cent two to six days after spraying, providing quick, convenient, and economical control and avoiding undesirable insecticide residues. Further trials will be necessary to determine suitable applications earlier in the season.
The effect of pre-treatment of native pasture and sowing rate on establishment of Townsville lucerne of Tippera clay loam at Katherine, NT
Authors: Miller HP
Published: March 2005

At Katherine, N.T., on Tippera clay loam soil, Townsville lucerne (Stylosanthes humilis H.B.K.) was sown in December 1965 at 4, 16, and 64 lb an acre of abraded pods into uncleared uncultivated perennial native pasture that had been subjected to three pre-treatments : heavy grazing in the previous wet season, late dry season burning, and early wet season burning. The amount and incidence of rainfall was particularly favourable for establishment. At counts made in December 1965, and in January and February 1966, pre-treatment did not affect Townsville lucerne density, which was proportional to sowing rate on all pre-treatments. Dry matter yields of Townsville lucerne in April 1966 were higher after early wet-season burning than after other pre-treatments. At a final seedling count at the start of the next wet season, December 1966, there was an interaction between pre-treatment and sowing rate, seedling density showing an approximate correspondence with dry matter yield of Townsville lucerne in April 1966. At the practical sowing rates of 4 and 16 lb an acre, first and second year seedling densities and first year yields were comparable with average figures for Townsville lucerne established with full land clearance and cultivation.
Estimation of nitrogen fixation by four legumes in a dry monsoonal area of north-western Australia
Authors: Wetselaar R
Published: March 2005

The amount of nitrogen fixed by the legumes Townsville lucerne (Stylosanthes humilis), guar (Cyamopsis tetragonoloba), cowpea (cv. Poona), and peanuts (cv. Natal common) on Tippera clay loam was determined in the field for three seasons of growth. The total amount added to the soil-plant system in the three seasons by the four legumes was respectively 196, 196, 240, and 111 lb nitrogen an acre. The results indicate that Townsville lucerne fixed annually 83 lb nitrogen an acre in the second and third season. Cowpea and peanuts fixed less in the second and third season because of an increase in available soil nitrogen. Only with guar and Townsville lucerne was the original nitrogen status of the soil maintained.
The nutritive value of some pasture species in north-western Australia during the late dry season
Authors: Robinson DW , Sageman R
Published: March 2005

The nutritive value of five pasture species, Mitchell grass (Astrebla elymoides F. Muell.), Flinders grass (Iseilema fragile S. T. Blake), native sorghum (Sorghum australiense Garber and Snyder), Birdwood grass (Cenchrtis setigerus Vahl), and buffel grass (Cenchrus ciliaris L.) harvested in the late dry season, were compared with a basic low quality roughage (rice straw, Oryza sp.) in digestibility trials with Peppin Merino sheep. Dry matter and organic matter digestibilities were Mitchell grass 45.2 and 48.2, Flinders grass 38.8 533 and 44.4, native sorghum 39.0 and 43.2, Birdwood grass 35.9 and 38.6, buffel grass 42.5 and 44.2, and rice straw 32.1 and 46.3. Voluntary dry matter intake, the concentration of ruminal ammonia and volatile fatty acids, and the digestible energy values were low with all species, and the possibility of primary energy deficiencies on dry season pastures is discussed. The efficiency of nitrogen utilization at low levels of nitrogen intake was higher than anticipated from published data, and further studies are in progress to verify these observations. The seasonal changes in chemical composition of the five pasture species studied are recorded in an appendix.
Nutritive values and chemical composition of seven tropical legumes and lucerne grown in subtropical south-eastern Queensland
Authors: Milford R
Published: March 2005

The chemical composition and feeding value of seven tropical legumes and lucerne were determined by pen feeding experiments with sheep. Most of the legumes were harvested during autumn and winter. Lucerne had the highest feeding value and the highest values for the tropical legumes were obtained for Vigna vexillata, Lotononis bainesii, and Desmodium uncinatum. After frosting, the feeding values of Phaseolus lathyroides and Vigna vexillata were reduced but that of Desmodium uncinatum was not changed. This may have been due to a greater loss of leaf by both P. lathyoides and V. vexillata than by D. uncinatum. Frost did not affect Lotononis bainesii and Medicago sativa, and both had a higher feeding value than the legumes affected by frost. The usefulness of crude protein and crude fibre for estimating dry matter digestibility and dry matter intake and the relation between dry matter digestibility and dry matter intake is discussed. The use of dry matter digestibility to express the nutritive value of feed energy in preference to organic matter digestibility, starch equivalents, and total digestible nutrients is also discussed.
Diuron as a pre-sowing herbicide for cotton in the Ord River Valley
Authors: van Rijn PJ
Published: March 2005

When cotton is sown in the middle of the wet season on the Ord River Valley, the formation or ridges and the control of weeds present major problems. One solution would be to complete the final land preparation, including the formation of the ridges, at the end of the dry season (November), and to spray with a herbicide, such as diuron, at the end of the dry or at the onset of the wet season. Four experiments concerned with this system are described. When diuron at 1 1/2-2 lb active ingredient an acre was applied during the dry season or at the beginning of the wet, cotton sown two weeks after spraying was not damaged and weeds were controlled throughout the growing season. When diuron was applied later on in the wet season (January-February), cotton could not be sown without seedling damage until approximately six weeks after spraying. Residues from annual applications of pre-sowing diuron to the same area did not accumulate fast enough to damage subsequent cotton crops.
Observations on the transport of nematodes in sub-soil drainage and irrigation water
Authors: Meagher JW
Published: March 2005

At Red Cliffs, Victoria, it has become an accepted practice to return drainage water to the irrigation supply. Observations on the numbers of nematodes collected from sub-soil drains, at different times of the irrigation season, have shown the persistent occurrence of parasitic nematodes. In particular, larvae of the citrus nematode Tylenchulus semipenetrans are present in high numbers. Because of the known importance of parasitic nematodes as factors in the yield reduction of horticultural crops in the Murray Valley, and the need to limit their spread, it is concluded that the re-use of drainage water for irrigation purposes is undesirable.
Some measurements of tree size
Authors: Culver R , Till MR
Published: March 2005

Estimates of the volume and surface area of citrus and peach trees were made from five lateral measurements of the tree profile on each of eight radials. These estimates were made from the field measurements with the aid of a computer. The computer programme took either the actual shape as measured, or assumed that the shape approximated simple geometric forms. These calculations were also made with several groupings of two or four of the radials to see how few observations could yield a significant evaluation of tree volume or surface area. Tree height, yield, and butt circumference were also measured. Using a further computer programme a linear regression analysis was carried out by which the various approximations of the actual volume or area were evaluated. The most efficient technique of measuring tree area or volume was to measure the tree profile on two or four radials and make the calculation without the use of an approximating form. As a single simple measure of tree size, height was in some cases superior to butt circumference. Yield was found to be not closely correlated with tree size.
Preliminary studies on the establishment of Townsville lucerne (Stylosanthes humilis) in uncleared pasture at Katherine, N.T
Authors: Miller HP , Perry RA
Published: March 2005

The effects of surface treatments, soil type and type of seed sown on the early establishment of Townsville lucerne (Stylosanthes humilis H.B.K.) in native pastures at Katherine, N.T., were studied on microplots in the 1965-66 wet season. In experiment 1, six soil surface treatments were compared in burnt and unburnt native perennial pastures on Tippera clay loam on three occasions. In experiment 2, seeds were compared with pods, cleared cultivated land with uncleared uncultivated land, and Tippera clay loam with Cockatoo sand on two occasions. The results indicate that, given favourable weather conditions, Townsville lucerne can be established on untreated soil surfaces in uncleared native pastures, either annual or perennial ; that weather conditions affect early establishment, presumably through the length of the period that the soil surface remains wet ; that seeds perform two to three times better than pods ; and that early establishment is approximately three times better in the presence of growing native pasture than in its absence, possibly because of the higher atmospheric humidity within the protective grass cover.
Stocking rate and the superphosphate requirements of sown pasture on an acid soil
Authors: McLachlan KD
Published: March 2005

The response by Phalaris-subterranean clover pasture to applied nitrogen, phosphorus, and sulphur was measured at two sites on the same soil. Both sites had the same fertilizer history. For the past fifteen years the stocking rate on one site had been maintained at not less than three times that of the other. Yield responses to phosphorus were obtained at both sites. The response at the lower stocking rate was greater than that at the high stocking rate. A similar response pattern was found for nitrogen, but the difference in response between the stocking rate treatments was not significant. The pastures did not respond to sulphur. The trend was for sulphur to depress the yield at both stocking rates. The evidence suggests that less superphosphate was needed to maintain pasture production at high stocking rates than at low ones. Available phosphorus, determined chemically, increased with grazing intensity. There was no evidence that a particular soil phosphorus fraction was associated with this increase, or the lower requirement for added fertilizer. The only significant difference between grazing treatments were increases in the iron, calcium, and organic forms at the higher grazing intensity. It is probable that the present pasture response, and hence the fertilizer requirement of the soil, was influenced more by the altered growth potential of the plants under grazing, than by the effect of grazing on the soil nutrient status.
Pasture growth curves and grazing management
Authors: Morley FHW
Published: March 2005

Growth curves, published by Brougham (1956), of pastures growing in winter at Palmerston North, New Zealand, were analysed. The mathematical models were examined by computer runs in which the various parameters were varied within likely limits. The results obtained suggest that the following principles may be applied to the management of pastures similar to those studied. The average rate of regrowth increases to a maximum after removal of grazing animals, but this maximum is not sharply defined. The optimum number of subdivisions in a rotational grazing system is probably less than ten, unless considerations other than pasture growth are important. The optimum length of intervals between grazings, and of grazing periods, for a given level of subdivision, are not sharply defined. Following dry autumns, management should generally aim at maximum pasture production rather than most rapid relief of present stress, provided this policy does not endanger animal or financial survival. Systems of grazing management may therefore vary within fairly wide limits, without serious loss of pasture production, provided pasture stability and animal welfare are not jeopardized.
Comparative productivity of some cultivars of subterranean clover (Trifolium subterraneum) in north-eastern Victoria
Authors: Cameron IH , McGowan AA
Published: March 2005

Eight cultivars of subterranean clover (Trifolium subterraneum L.)-Yarloop, Burnley, Bacchus Marsh, Nangeela, Clare, Portugal, Chiltern Valley, and Mt. Barker-were compared in mowing experiments at the Rutherglen Research Station in north-eastern Victoria. All eight had similar total annual yields of dry matter, but all except Chiltern Valley outyielded Mt. Barker (the common district cultivar) in most winters. Yarloop, Burnley, and Bacchus Marsh grew best in winter. Of these, Burnley has most promise, being apparently more persistent than Bacchus Marsh, and having lower oestrogenic potency than Yarloop. There was no difference in greasy wool production from wethers run at five to the acre on Mt. Barker or Bacchus Marsh pastures, despite higher pasture production on the latter. Hay was cut in two seasons ; after feeding equal amounts to each group of sheep, there was a surplus of 20 cwt an acre in favour of the Bacchus Marsh pasture. Clover seed production, winter pasture growth, and sheep liveweights also favoured Bacchus Marsh.
An evaluation of several soil tests for predicting wheat yield response to superphosphate in Victoria
Authors: Mullaly JV , Skene JKM , Jardine R
Published: March 2005

The predictability of three different measures of wheat yield response to superphosphate from each of four soil test measures of available phosphorus (0-6 inches) was examined, using data from field experiments over the period 1951 to 1965. The associations were studied separately within the three great soil groups that are dominant over the wheatgrowing areas of Victoria. Whichever measure of yield response was considered, soil bicarbonate P test measurement gave the best basis for prediction. However, at most, only 26 per cent of the yield response variability was predictable, and the other three tests were substantially less successful. Under the general conditions considered, where yield response is subject to a variety of uncorrected environmental deficiencies, it is concluded that the soil tests for P investigated in this paper are of doubtful practical value.
The effect of wet season land treatment and nitrogen fertilizer on safflower, linseed, and wheat in the Ord River valley. 1. Soil and crop nitrogen
Authors: Wetselaar R , Beech DF
Published: March 2005

Safflower, linseed, and wheat were grown under irrigation at Kimberley Research Station in the 1964 dry season following 6 and 18 month clean and weedy fallows. Four levels of nitrogen fertilizer, as ammonium sulphate and urea, were superimposed. Crop nitrogen yields were highest after 18 months clean fallow, and were highly correlated with the amount of nitrate-nitrogen that had accumulated in the soil profile during the preceding fallow period. For wheat, which was the most efficient user of mineral nitrogen, 160 lb nitrogen an acre as ammonium sulphate was required after 18 months weedy fallow to equal the crop nitrogen yield after 18 months clean fallow without nitrogen fertilizer. The mean crop nitrogen yield with urea was only 76.7 per cent of that with ammonium sulphate. The results indicate that the form, and possibly the distribution, of mineral nitrogen in the soil in the early stages of crop growth could be important factors determining the efficiency of nitrogen for optimum plant performance.
The effect of wet season land treatment and nitrogen fertilizer on safflower, linseed, and wheat in the Ord River valley. 2. Safflower and linseed
Authors: Beech DF , Norman MJT
Published: March 2005

Gila safflower and RR 204 linseed were grown under irrigation at Kimberley Research Station in the 1964 dry season after 6-months and 18-months clean and weedy fallows. Four levels of nitrogen fertilizer, as ammonium sulphate and as urea, were superimposed. Seed yield responses to nitrogen fertilizer up to 80 lb N an acre (safflower) and 160 lb N an acre (linseed) were obtained after weedy fallows, but after 18 months clean fallow neither crop showed a significant response to nitrogen fertilizer up to 160 lb N an acre. Ammonium sulphate was more effective than urea at equivalent rates of nitrogen per acre. The amount of nitrate-nitrogen in the top three feet of soil shortly before planting was related to the total nitrogen yield of linseed at maturity, which, in turn, was closely related to seed yield. Increases in seed yield of linseed with clean fallowing and nitrogen fertilizer were largely the result of increases in bolls per plant and 100-seed weight.
Perennial and annual pasture species in the control of Silybum marianum
Authors: Michael PW
Published: March 2005

Experiments begun in 1958 near Boorowa in the south-west slopes of New South Wales, have demonstrated the superiority of the perennials Hunter River lucerne (Medicago sativa L.) and Phalaris tuberosa L. over the annuals, Wimmera ryegrass (Lolium rigidum Gaud.) and subterranean clover (Trifolium subterraneum L.) in reducing establishment and growth of the annual thistle, Silybum marianum (L.) Gaertn. At one harvest (1959) the fresh weights of thistles varied from 0 in lucerne and 1 or 2 tons an acre in Phalaris to about 11 tons an acre in the annual plots. At another harvest (1960) the dry weight of thistles varied from about 0.2 cwt an acre in lucerne and Phalaris to about 5 cwt an acre in ryegrass plots. In the period of the experiment (mid 1958 to early 1967) there was an 85 per cent reduction in the numbers of apparently viable seeds of Silybum present in the soil of plots sown to lucerne and Phalaris.
The value of the seed, pods, and dry tops of subterranean clover (Trifolium subterraneum) in the summer nutrition of sheep
Authors: Wilson AD , Hindley NL
Published: March 2005

Penned sheep were fed a protein deficient ration of mature ryegrass (Loliumrigidum Gaud.) supplemented by the seed, pods, or dry tops of Trifolium subterraneum L. The supplements did not increase the intake of ryegrass, but all supplements did increase the total feed intake. With the pod supplements, total intake was increased by increasing the level of supplement from 100 to 200 g a day, but there were no other differences between the levels or types of supplement. Bodyweight losses decreased in proportion to the increases in intake. It was concluded that small intakes (100-200 g) of clover pods or dry tops produce significant reductions in the weight loss of sheep, but that further increases in the amounts eaten are of no value for reducing weight loss as the digestibility of all constituents is similar. The nitrogen content of oesophageal fistula samples collected from dry pastures of Wimmera ryegrass and subterranean clover was not decreased by the absence of clover pods. It was concluded that the dry tops of the clover are at least as important as the pods in the nutrition of sheep in summer.
The effect of plant size and developmental stage on summer survival of some perennial grasses
Authors: Hoen K
Published: March 2005

Observations on summer survival in sown swards of a number of cultivars of Phalaris tuberosa L., P. coerulescens L., Dactylis glomerata L., and Hordeum bulbosum L. were made at Wagga Wagga, New South Wales, in two consecutive years with widely different rainfall patterns. In both years survival was higher among reproductive plants than among vegetative plants, and in both types of plants the largest individuals had the highest survival rates. In the abnormally dry year 1965 only a number of cultivars of cocksfoot had adequate survival rates. Some agronomic practices aimed at maximum survival over the first summer are discussed.
The influence of gypsum particle size on pasture response on a sulphur deficient soil
Authors: McLachlan KD , De Marco DG
Published: March 2005

The pasture response to four particle sizes of gypsum fertilizer was measured on a sulphur deficient basaltic soil over a three-year period. At a low rate of application, pasture response was inversely related to particle size ; at a higher rate, only the coarsest fraction differed from the other treatments. The reduction in plant sulphur content and uptake with this fraction suggests that particles >5 mm may be approaching the upper limits of usefulness on this soil. In the first year, the negative interaction between particle size and level of gypsum applied showed that particle size may replace level of application in its effect on response. More efficient use of the sulphur in the fertilizer resulted from application of the finer fractions. Separation of particle size effects into those due to rate of solution of sulphur from the compound, and those due to placement through physical distribution over the soil surface, showed that rate of solution of sulphur was the more important variant. Recognition of its influence could lead to prescribing the correct particle size of gypsum for every sulphur deficient soil. The main effect of the applied sulphur was on the clover component of the pasture. The results suggest that a sulphur content of 0.07 per cent in mature plant tops may be a critical value indicating an adequate sulphur supply, and that 5 lb sulphur an acre in the plant tops may be all that is required for maximum clover production.
Nitrogen fertilizer and wheat in a semi-arid environment. 2. Climatic factors affecting response
Authors: Russell JS
Published: March 2005

The response of Gabo wheat to nitrogen fertilizer at 52 sites in the wheat growing areas of South Australia during 1956-61 was examined in relation to climatic factors by a stepwise multiple regression analysis using a computer. The ten dependent variables were the linear and quadratic coefficients obtained by fitting orthogonal polynomials to response curves of various parameters (grain yield, grain + straw yield, harvest index, grain nitrogen percentage, and grain nitrogen yield) to applied nitrogen at each of the 52 sites. The 23 independent variables were the amounts of rainfall and evaporation during the growing period, maximum and minimum temperatures and estimates of high temperature stress during spring and amount of rainfall immediately after sowing at each site. The climatic variables examined explained 46.5, 64.3, and 64.3 per cent of the variation in the response to nitrogen fertilizer of grain yield, grain + straw yield, and grain nitrogen yield respectively. The positive effects of increasing amounts of winter rainfall on yield response to applied nitrogen were marked. On the other hand, the negative effects of high maximum temperatures in the latter part of the growing period, particularly during October, on yield response were also evident.
The dyebanding and tattooed patch procedures for estimating wool production and obtaining samples for the measurement of fibre diameter
Authors: Langlands JP , Wheeler JL
Published: March 2005

The dyebanding and tattooed patch techniques of estimating wool production were compared in three experiments, and in two of these, mean diameters of wool fibres taken from the tattooed patches and from the dyebands were also determined. There were significant differences at some times of the year between the two estimates of wool production and in fibre diameter in two of the experiments. Possible reasons for these differences are discussed. The dyebanding and tattooed patch techniques appeared to be of similar precision, and the errors associated with these techniques were small compared with the variation between sheep. It is suggested that, where possible, the experimental design should be modified to include a preliminary period so that wool growth during this period can be used as a covariate.
Nutritive evaluation of two strains of mature subterranean clover
Authors: Hume ID , Somers M , McKeown NR
Published: March 2005

The relationship between the in vivo and in vitro digestibility of leguminous herbage was examined. Further studies were made using in vivo-in vitro digestibility estimations to compare the nutritive value to sheep of two strains (Yarloop and Woogenellup) of subterranean clover. The digestibilities of the main component parts (viz. stem, petiole, leaf, and burr) of the plants of each strain were also estimated in vitro. Digestibility differences between strains and between parts were examined on the basis of the chemical composition of their dry matter. Woogenellup was significantly more digestible than Yarloop, both in vivo and in vitro. Voluntary intake of Woogenellup was also significantly greater than that of Yarloop. The in vitro digestibility of stem did not differ significantly from that of petiole. Nor did the digestibility of leaf differ significantly from that of burr. However, the digestibility of stem and petiole together was greater than that of leaf and burr together. These findings are discussed in relation to their possible biological significance.
Comparison of the efficiencies of several nitrogen fertilizers applied to pasture in autumn and winter
Authors: Simpson JR
Published: March 2005

A comparison was made of the responses to, and nitrogen recoveries from, ammonium sulphate, sodium nitrate, and urea when broadcast on a ryegrass sward in a favourable growing season. A second comparison was made, in a drier season on the same sward, between ammonium sulphate, sodium nitrate, urea, calcium ammonium nitrate, and ammonium nitrate. In both comparisons urea was an inefficient source of nitrogen, but its efficiency depended on the time of application. Differences in the rainfall shortly after application probably caused this variation in efficiency, by affecting the amounts of ammonia lost to the atmosphere. With sources other than urea, variation in the length of time during which the fertilizer remained at the soil surface, awaiting effective rainfall and plant uptake, had little effect on the final recovery of nitrogen. Ammonium sulphate, calcium ammonium nitrate, and ammonium nitrate showed similar efficiencies during the relatively dry season in which they were compared. Sodium nitrate was the most efficient source in both seasons.
The effectiveness of nodulation of a wide range of lucerne cultivars
Authors: Leach GJ
Published: March 2005

The effectiveness of nodulation of a wide range of lucerne cultivars-growing in a sandy soil and inoculated with a commercial preparation of inoculum-varied widely, and problems appeared In two distinct groups of cultivars. The first group comprised cultivars derived at least partly from the M. falcata genotype, and with these there were problems both of ensuring nodulation and in the level of effectiveness. The second group included winter-active cultivars from around the Mediterranean Basin, among which were African and Hairy Peruvian. All plants were well nodulated, and the level of effectiveness appeared to be the only problem. Although the effect on yields was smaller in the second group than in the first, it is nevertheless one which anyone engaged on the production of improved lucerne cultivars from these potentially very useful genotypes must resolve.
Competition between rice and barnyard grass (Echinochloa). 1. The influence of weed density and nutrient supply in the field
Authors: Kleinig CR , Noble JC
Published: March 2005

In a field trial at Deniliquin, N.S.W., the density of Echinochloa seedlings was found to be inversely related to the final grain yield of rice (Oryza sativa). Echinochloa tillered earlier than rice, and increasing nutrient supply encouraged more rapid tillering. Echinochloa competition reduced the number of rice tillers, panicles, and spikelets per panicle, and these effects were accentuated at high levels of nitrogen and phosphorus application. The percentage of grain filled spikelets was unaffected by increasing Echinochloa density except at high nutrient levels. Superphosphate did not increase the yield of rice, even in the absence of Echinochloa competition. The response by rice to nitrogen was reduced in the presence of barnyard grass. At high weed densities, crop failure resulted when phosphorus and high levels of nitrogen were both applied.
The relationship between the spore density of Cochliobolus sativus in soil and its saprophytic activity and parasitism
Authors: Burgess LW , Griffin DM
Published: March 2005

Both saprophytic colonization of wheat straw and seedling infection by Cochlioholus sativus (Ito and Kur.) Drechsl. ex Dastur, which causes common root rot of wheat, were correlated with spore density. The results indicate that straw colonization is possible at 10�C even when the spore density is too low to cause seedling infection. Saprophytic activity may thus raise the spore density over the threshold necessary for parasitism.
The importance of weight loss in reducing breakdown of Jonathan apples
Authors: Scott KJ , Roberts EA
Published: March 2005

Studies were made of the effect of different treatments on weight loss and breakdown of Jonathan apples. The apples were stored at 30�F under high relative humidity except while the following treatments were applied : initial storage at 30�F for 2, 4, 6, 8, and 10 weeks at 65 per cent relative humidity ; storage at 30�F over calcium chloride for 8 weeks ; hydrocooling ; step-wise cooling from 36�F to 30�F ; and warming the fruit at 68�F for 24 hours. The level of breakdown in all treatments depended on the loss in weight of the fruit. Initial storage at low humidity appears to be a practical method of reducing breakdown.
Observations on the response of Merino weaners to a fodder supplement, a feeding block, and cobalt and selenium treatments
Authors: McInnes P , Roberts BC , Finlayson PM , Russel JV
Published: March 2005

Summary-The response to supplementary feeding of weaners was studied at Condobolin, New South Wales. Three equal groups of 120, 3-4-month-old Merino weaners were rotated every six weeks for 18 weeks in a three-paddock system. The pasture consisted mainly of relatively dry heliotrope (Heliotropitlm europaetm) but there was some green fodder provided by other pasture species. Unsupplemented weaners gained 54 g per day and a group supplemented with unrestricted amounts of a hammerrnilled mixture of three parts chopped lucerne hay and one part oat grain gained an additional 7 g per day (P<0.05). The mean greasy fleece growth of the supplemented group (2.86 kg) between birth and approximately 10 months of age was greater than the unsupplemented group (2.68 kg, P*lt;0.05). The cost of the supplement would appear to be greater than the increased returns. Weaners allowed unrestricted access to a mineral feeding block gained a mean weight of 42 g per day which was significantly less than the unsupplemented group (P<0.05) and failed to maintain weight during the last six weeks of the trial. Selenium and cobalt treatments, which were given to some sheep in all groups, did not affect body weight gain or wool production.
The effect of age and method of haymaking on the digestibility and voluntary intake of the forage legumes Dolichos lablab and Vigna sinensis
Authors: Milford R , Minson DJ
Published: March 2005

Cowpea sown in January and harvested in April had a higher dry matter digestibility and voluntary intake in comparison with Dolichos. When field cured for 20 days, differences in digestibility and voluntary intake were not significant between species, and levels of both were markedly reduced. Intermediate levels for digestibility and voluntary intake were obtained after field curing for 8 days. Dry matter digestibility of Dolichos declined at subsequent first growth harvests in May, July, and August but voluntary intake for the April, May, and August cuts was similar.
Protein digestibility in sheep and cattle in north-western Australia
Authors: Robinson DW , Stewart GA
Published: March 2005

Three experiments were conducted at Kimberley Research Station, Western Australia, one with local Shorthorn cattle and two with Peppin Merino sheep from the Abydos region of Western Australia, to study the protein digestibility of various combinations of low-quality roughage and protein-rich concentrates. The relationship between the crude protein and digestible crude protein content of the feed was for cattle : % DCP = 0.832% CP - 1.58 and for sheep : % DCP = 0.865% CP - 2.21 indicating a higher ability to digest protein compared with previous values in the literature for cattle and sheep. It is suggested that the difference may be due to a high degree of adaptation to semi-arid conditions of local sheep and cattle in north-western Australia.
The influence of supplementary feeding on growth and fertility of beef heifers grazing natural pastures
Authors: Sparke EJ , Lamond DR
Published: March 2005

This paper reports an experiment examining the effect of age and protein supplementation on growth and fertility of Shorthorn-Devon cross heifers grazing natural pastures in the summer rainfall, subtropical environment of the Upper Clarence valley, north-eastern New South Wales. Heifers born over the period October to January 1963-64 were weaned in June 1964 and allotted at random within age groups (by month of birth) to a supplemented or non-supplemented treatment. The supplemented heifers were given linseed meal during the dry winter period each year from 1964 to 1966 inclusive (May-June to September-October). They were weighed each month and joined with bulls in the early summer of 1965 (2 years) and 1966 (3 years). They were examined for pregnancy in the autumn, and their calves were identified at birth. Supplemented heifers gained weight throughout and non-supplemented heifers generally lost weight in the winter periods. At two years fertility was closely related to liveweight at joining in supplemented heifers, but not in others. Heifers born in January gave the poorest reproductive performance, as the two supplemented ones that became pregnant in 1965 died at calving, and two-thirds of the non-supplemented ones were still empty after joining as 3-year-olds. The advantage of high 2-year-old fertility gained by heifers born in October and November, due to their greater size at joining, was partly offset by low fertility when lactating the following year. It is concluded that a decision as to whether a heifer should be supplemented during a period of nutritional stress prior to joining ought to be based on the probability of her reaching a prescribed target weight at joining as a result of receiving the supplement. The target weight for lactating heifers was at least 100 Ib higher than for dry hdfers. The results also indicate specific areas for further research.
Grazing trials on the Wallum of south-eastern Queensland. 1. A comparison of four pastures
Authors: Bryan WW
Published: March 2005

Four pastures, based respectively on Paspalm dilatatum, P. commersonii, P. plicatulum, and Digitaria decumbens, were grazed by beef cattle at Beerwah from 1959 to 1965. Mean annual liveweight gain was 244 lb an acre, and the best pastures produced 262 lb an acre. The pattern of liveweight change was of gain in summer and early autumn (mean 0.99 !b a head a day), no change in late autumn and winter, and a higher rate of gain in spring and early summer (mean 1.55 lb a day). This pattern was related partly to the changing condition of the pasture and partly to animal factors. Only on the Paspalum plicatulum pasture was there a weight loss in winter. The legume content of the pastures was low, only 13 per cent, and this had a major influence on the results. The main legumes were Desmodium uncinatum, Lotononis bainesii, and Trifolium repens. Nitrogen content of the pastures was below 1 per cent in autumn and winter, and at these seasons the quantity of digestible crude protein was probably insufficient to maintain animals in positive nitrogen balance. Quality improved in spring, and, although the total available dry matter was low, animals thrived at that time. It seems clear that the measurements made on these pastures did not fully reflect the diet of the grazing animals.
Initial and residual effects of superphosphate on a Townsville lucerne pasture in north-eastern Queensland
Authors: Jones RK
Published: March 2005

The responses to superphosphate of a Townsville lucerne (Stylosanthes humils)-grass pasture on a solodic soil near Townsville, were measured for three years. An initial dressing of 784 lb an acre gave the highest yield of dry matter for the three years, but 336 lb an acre was almost as effective. Applying 336 lb in equal annual dressings of 112 lb an acre gave less total dry matter but slightly more nitrogen and phosphorus per acre than 336 lb initially. On this soil type superphosphate had a good residual effect. Pastures with initial dressings of 336 1b or more outyielded the controls in all years, and did not respond to maintenance dressings applied in the second and third years. Superphosphate increased the yields of phosphorus per acre by increasing the phosphorus contents of both Townsville lucerne and grass as well as the dry matter yields. It had little effect, however, on the nitrogen contents. The relation between the phosphorus content of the pasture and the yield of dry matter was examined and tentative critical values were established.
Nitrogen fixation by lucerne on several soils in pot culture
Authors: Holford ICR
Published: March 2005

Nitrogen fixation by lucerne (Medicago sativa) was measured on ten agricultural soils in pot culture. There was a three-fold variation in nitrogen fixation, smallest quantities being fixed on a red brown earth, a euchrozem, and a wiesenboden. Both lucerne yield and nitrogen fixation were significantly correlated with soil pH over a range of 6.2 to 8.6 when phosphorus and sulphur were applied. These two nutrients caused significant increases in lucerne yields and nitrogen fixation on all soils. Fixed nitrogen originating solely from the underground parts of the lucerne plants caused significant increases in the nitrogen yield of wheat grown subsequently on the same soils.
Effects of season, maturity and rate of nitrogen fertilizer on ensilage of Setaria sphacelata
Authors: Catchpoole VR
Published: March 2005

A study was made of the chemical composition and silage fermentation of Setaria sphacelata CV. Nandi. The grass was ensiled at three periods of the growing season, with two maturities at harvest, and grown with two levels of nitrogen fertilizer. On each harvest day cuts were taken in the morning, at noon, and in the afternoon. The object was to measure the variation that occurred under field conditions in south-eastern Queensland. The water soluble carbohydrate content of the grass was always below 6 per cent of its dry weight, and the silage had very low contents of lactic acid, high contents of volatile acids and high pH values. Volatile base contents were usually well below 20 per cent of the total nitrogen, showing that degradation of protein was not extensive. By traditional standards of silage quality the S. sphacelata was poorly preserved. On the other hand a degree of preservation was achieved as shown by the moderate amount of protein breakdown and small losses of dry matter and nitrogen during storage. Variation in the extent of fermentation changes, and of losses during ensilage, demonstrated that grass cut at five weeks was more effectively preserved than grass cut at eight weeks. Also, on any one harvest day, grass cut during the morning had lower dry matter contents, and was not as well preserved as cuts made later during the day.
The response to row spacing of two tropical rice varieties of contrasting plant type
Authors: Owen PC
Published: March 2005

The growth of two rice varieties of contrasting plant type and of different origin was compared at two row spacings under wet season tropical conditions in northern Australia. The short, erect-leaved variety SML 81b responded to the closer spacing by producing fewer tillers and a smaller leaf area per plant during active vegetative growth. The tropical leafy variety Sircna did not exhibit any compensatory reduction of the growth of individual plants, and dense crop growth and high leaf area indices resulted at the closer spacing. The heavy vegetative growth of Sircna was not reflected in grain yield at harvest, while the higher tiller number per unit area of SML 81b resulted in a higher grain yield at the closer spacing. The agricultural implications of the results are discussed.
Leaf area durations and grain yields of two tropical rice varieties
Authors: Owen PC
Published: March 2005

A series of differing leaf area index regimes during the growth of two tropical rice varieties was produced by partial defoliation at different growth stages. In addition, part of the crop was completely defoliated after panicle emergence. Comparison of the effects of the range of leaf area durations (D) thus produced showed that these rice varieties differed from temperate climate cereals. Grain yields were least associated with D after panicle emergence, but were most influenced by D before emergence. This effect is mainly via an influence upon the number of spikelets formed per panicle. Grain : leaf ratio, a measure of photosynthetic efficiency, was considerably lower than values reported for wheat.
Control of grasshoppers (Phaulacridium vittatum) by ultra-low volume aerial application of technical maldison
Authors: Casimir M
Published: March 2005

Field trials investigating ultra-low volume applications of undiluted technical maldison by aircraft against dense populations of Phaulacridium vittatum Sj�stedt (wingless grasshopper) are described. In February 1965 an application rate of 8.2 fl oz an acre gave 90-95 per cent reduction of grasshopper populations on a property on the northern tablelands of New South Wales. A further trial in November 1965, using rates of 4.6 and 5.6 fl oz per acre, gave similar results for each rate-70 per cent reduction of the population one day after spraying, rising to 80-85 per cent within eleven days. Some aspects of a large aerial spraying campaign conducted from October to December 1965 are also described. More than 150,000 acres were treated with maldison at the rate of 6.3 fl oz an acre. Detailed observations of the campaign spraying were made on a single property as well as general surveys of the whole treated area. A minimum application rate of 8.0 fl oz maldison an acre is suggested for normal field usage against P. vitiatum.
Hepatic copper concentration of steers grazing pastures on developed wet heath land in south-eastern Queensland
Authors: Gartner RJW , Young JG , Pepper PM
Published: March 2005

A 2 X 2 factorial design was used to investigate the effects of copper and cobalt therapy of Hereford steers grazing Lotononis-Pangola pastures on the wet heath areas of coastal south-eastern Queensland. Copper was given as a subcutaneous injection of copper glycinate and cobalt as an intra- ruminal cobalt oxide pellet. Liver samples were obtained at three-monthly intervals for 18 months. The liver copper concentration of untreated animals decreased to low levels (<10 p.p.m.). Copper therapy increased (P<0.01) and cobalt therapy decreased (P<0.01) liver copper levels. There were, however, no significant differences in bodyweight gains.
Seasonal production and persistence of a collection of introduced lucernes
Authors: Crawford EJ
Published: March 2005

The persistence and seasonal production of six cultivars of lucerne (Medicago satiua) were compared with the Hunter River cultivar over a four-year period at the Parafield Research Centre, via Salisbury, South Australia. Considerable differences in seasonal production were demonstrated, African (C.P.I. 21610) producing 133 per cent more winter production than Hunter River over a three-year period. Lack of persistence in the winter vigorous cultivars had an adverse effect on production in the fourth year. Hunter River was the most persistent cultivar over the life of the trial and was not exceeded in production after the third summer.
The growth of barley grass (Hordeum leporinum) in annual pasture. 4. The effect of some management practices on barley grass content
Authors: Smith DF
Published: March 2005

The effects of three grazing treatments and three mowing treatments on the dominance of barley grass (Hordeum leporinum) in an annual pasture were examined. Different spring grazing patterns did not markedly alter the amount of seed. Mowing favoured the legume component; topping less so than cutting lower as for hay or silage. However, none of these practices totally prevented barley grass from setting seed, and their effects were partly offset by late irrigation. Oversowing with subterranean clover (Trifolium subterraneum) did reduce barley grass seed setting but alone u-as not effective in changing botanical composition. Compared with Wimmera ryegrass (Lolium rigidum), barley grass showed greater persistence.
Growth and development of buffel grass (Cenchrus ciliaris)
Authors: Burt RL
Published: March 2005

Buffel grass (Cenchrus ciliaris), an important subtropical forage species, was grown under a range of environmental conditions; growth and development were followed by a series of regular harvests. The rates of plant growth and development increased with increasing levels of solar radiation up to the highest levels received (approximately 700 cal/cm2/day). The distribution of dry matter between the various plant organs was relatively unaffected by changes in temperature or mineral level ; differences in partitioning apparently occurred with respect to light intensity, root growth being restricted at the time of flower development at the lower intensities. The implications of the results are discussed with emphasis on possible differences between subtropical and temperate grass species.
Effect of clipping on yield of wheat
Authors: Dann PR
Published: March 2005

Wheat (CV. Heron) was subjected to various clipping treatments at Yanco, New South Wales, in 1963 and 1964. Clipping of vegetative growth decreased straw and grain yields in both years, but the decline in yield was much greater in 1963 than in 1964. Weight per grain was the major grain yield component reduced by clipping. Highly significant correlation; were obtained between dry matter removed at clipping, weight per grain, and grain yield.