摘要:

Three trials were carried out to compare the feeding value of silage and barn‐dried hay for fattening bullocks of approximately 8 cwt initial body weight. In each case the silage and hay were cut from the same sward at the same time. In the first trial the bullocks fed on hay gained 1·88 lb/day while those self‐fed on silage gained 1·55 lb/day during a 70‐day feeding period. In the second trial of 70 days, the bullocks fed on hay gained 1·96 lb/day and those fed on silage from a trough gained 2·39 lb/day. In the third trial, individually‐fed bullocks housed in stalls and given the same hay and silage as used in Trial 2 gained 123 lb/day on hay and 127 lb/day on silage. The significance of these results is discussed in relation to the findings of ot

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00361.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A method is presented which gives an accurate estimate of the botanical composition of grassland on a dry‐weight basis, without the necessity of cutting and hand‐separating samples. In a number of quadrats an observer estimates which species take first, second, and third place in terms of dry‐weight. The data are tabulated to give the proportion of quadrats in which each species received first, second, and third place. These proportions are multiplied by 70·2, 21·1, and 8·7, respectively, and added to give the dry‐weight percentages of each species.The dry‐weight‐rank method was tested four times by comparing the results with those of hand‐separating cut samples. No great differences between the two methods were detected when exact rankings, obtained from hand‐separating, were used, and it was found that ranks could be estimated accurately, provided that sufficient training had been give

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00362.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

Viruss damage was observed on plants ofLolium perenneL. andDactylis glomcrataL. undergoing growth‐analysis studies. On the basis of visual symptoms the damage was presumed to be caused by barley‐yellow‐dwarf virus (BYDV) in ryegrass and by streak virus (CSV) in cocksfoot. The number of plants which could be clinically diagnosed as infected and the degree of damage were both positively correlated with temperature. It was inferred that at low temperatures both viruses could remain relatively inactive, or even latent. This was subsequently confirmed by removing cocksfoot plants from a heated glasshouse (19°–23°C) to a cold environment (6–10°C) which resulted in a progressive loss of symptoms in newly developing leaves. Some possible explanations and practical implications are brief

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00363.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A comparison of 3 systems of creep grazing, at a stocking rate of 6 ewes and 12 lambs per acre, indicated that lambs on a set‐stocking management with a lateral creep area grew at a significantly (P<0·05) slower rate than lambs folded with a lateral creep area or those rotationally grazed with a forward creep area. A similar difference was apparent in the ability of the managements to maintain the ewes liveweights. However, it is suggested that these results were not the direct outcome of the applied treatmentsper se. Parasite burdens in the lambs were low on all the treatments and there were no significant differences between th

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00364.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

Pure cultures and mixtures of equal numbers of plants of Irish. New Zealand and S23 perennial ryegrass were grown in artificially constructed swards under field conditions. They were cut every time they reached grazing height for three successive years. Counts of plant numbers and tiller numbers per plant made each November show that S23 suppressed both plant number and tiller number per plant of Irish ryegrass and to a lesser extent of New Zealand perennial ryegrass. Its own plant number and tiller number per plant were improved in these combinations. New Zealand perennial ryegrass suppressed plant and tiller numbers of Irish perennial ryegrass.Varying the method of cutting to match the growth of each variety resulted in improved plant survival and tiller number per unit area of Irish perennial ryegrass when cut according to the growth of S23, i.e. late in the spring. The importance of the effect of experimental technique is discussed.

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00365.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

In Saskatchewan, intermediate wheatgrass (Agropyron intermediumHost. Beauv.) suffered severe winter injury during the 1961–2 winter season, which followed a series of drought years, the most severe being 1961. In two tests, designed to study fertilizer effects, the extent of severe winter injury increased with the rate of application. The killing ranged from 4% where no fertilizer was applied to 90% where 66 lb of N per acre were applied. Slightly more winter‐killing occurred after applications of ammonium phosphate/sulphate (16‐20‐0) fertilizer than after ammonium nitrate (33·5‐0‐0).The grass growing in rows 36 in. apart killed out to a greater extent than that growing in rows 18 in apart Less winter injury occurred after spring applications of fertilizer than after application

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00366.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

The dairy‐cow results are presented from an experiment in which the response to grass irrigation was measured at two stocking rates. The method and herbage results have already been described (1).Over two years, with an average application rate of 5·5 in of water per year, the main effect of irrigation was to increase the number of grazing days obtained by 35%. Neither yield per cow nor milk quality was significantly affected by the treatments.The data emphasize the importance of high stocking rates for the full exploitation of irrigation. The practical implications of the results are discussed; they suggest that in the right circumstances of herd potential and grassland management, irrigation for milk production can be highly profitab

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00367.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

A seasonal herbage dry‐matter yield of 2400 lb/acre was obtained on a soil which by chemical analysis was infertile. Fertilizer treatment doubled yield. Monthly cuttings more than halved the yield but increased the mineral content. The highest levels of ash (8·04%) and nitrogen (3·75%) were obtained on the unfertilized sward in August, under the combined effect of sheep grazing and monthly clipping. Phosphorus levels were very low: 0·002% in the soil and 0·11% (August) in the grazed sward. The effect of varying cutting regimes and of a fertilizer treatment in the first year on yields over 4 years was measured. Little difference was detectable in the final year. Variability in the mineral content was found during the season. The August levels, under enclosure, on a dry‐weight basis, were: ash 5·58%, calcium 0·45%, nitrogen 2·05%, phosphorus 0·13%, potash 1·75%, sodium 0·04% and ma

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00368.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

Over three years, eight replicated experiments were conducted in which winter wheat was sown after a ley with and without seedbed applications of P and K. Fertilizer N was applied at 0, 45, 90 and 135 lb per acre in one dressing in early spring. Observations were made on tiller counts, grain size and yield.There were no significant interactions between N and mineral fertilizer. Mineral fertilizer had no important effect on tillering or grain yield. Consideration of the previous fertilization of the pastures showed that there was probably an adequate reserve of P and K in the soil, although soil analysis did not always reveal it.Nitrogenous fertilizer significantly increased fertile tiller numbers and raised yield of grain up to an application of 45 lb N per acre in 1960 and 90 lb N per acre in 1961 (after a wet winter). The average responses to 90 lb per acre of N after leys were 74, 6·3 and 101 cwt grain per acre in 1959, 1960 and 1961, respectively. In 1961 the corresponding response in an arable field was 16·3 cwt.It is concluded that after a well‐fertilized ley neither mineral fertilizers nor N are necessary in the seed bed and that the ley contributes about 45 lb N per acre towards the succeeding crop. The practical advantages of autumn drilling without fertilizer are stressed and reference is made to the importance of considering fertilizer applications for the rotation as a wh

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00369.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY

摘要:

Moisture losses from swaths of long herbage were recorded on eleven occasions in May, June and September, in order to supply data on which to base advice on making prewilted silage. Mowing in the late afternoon and picking up the following afternoon and mowing in the morning and picking up in mid‐afternoon both resulted in losses averaging 9·6%. These losses occurred in fairly dry weather throughout the season, even when it was cloudy and cool. Mowing in the late afternoon and picking up next morning, before dew or overnight rain had evaporated, resulted in negligible losses, averaging only 2

ISSN:0142-5242    

DOI:10.1111/j.1365-2494.1963.tb00370.x

出版商:Blackwell Publishing Ltd    

年代:1963

数据来源: WILEY