ALBERT

Description: The question of the composition of sugar beet tops and their utilisation for feeding purposes has been dealt with in a recent publication (l). The purpose of the present communication is to record the results of investigations into the problem of the preservation of sugar beet tops by the method of ensilage. The account falls naturally under four headings:I. Ensilage of sugar beet tops alone.II. Ensilage of sugar beet tops mixed with wheat chaff.III. Ensilage of sugar beet tops mixed with wet sugar beet pulp.IV. Nutritive value, as determined by digestion trials on sheep, of the silage obtained from the mixture of tops and pulp.

Description: In 1883 Mr George Fry, F.L.S. described a series of observations which he had made upon silage. From these he drew the conclusion that if the conditions of silage making were such that the temperature exceeded 45° C. sweet brown silage resulted, but that if the temperature failed to rise above 40° C. then sour silage with a rather repulsive odour was produced. These results were obtained in the type of silos then commonly in use, which varied in depth generally between 12 and 18 feet, frequently had a considerable surface area and were filled comparatively slowly.

Description: Experiments have been described which had primarily as their object the investigation of the effect of varying moisture content in the green oat and tare crop on the type of silage produced from such forage. The magnitude of the changes affecting the constituents of the green crop under the different conditions of ensilage have also been detailed.The main conclusions are summarized below:

Description: One of the main problems confronting the advocates of silage in this country is the selection of crops suitable for being grown for ensilage purposes, particularly in view of the fact that attempts to produce maize silage in this country have frequently been unsuccessful. It has been demonstrated, in trials extending over a number of years at Cambridge, that the mixed oat and tare crop can be used for the production of silage with success. The silage from oats and tares, when made under favourable circumstances, is possessed of great palatability and excellent nutritive value, and moreover, the process, considered from the point of view of losses of ingredients as a result of silo fermentation, is, if anything, more economical than that by which maize forage is converted into silage (1).

Description: The methods usually employed for estimating calcium carbonate in soil are all subject to more or less serious practical difficulties when the percentage of lime falls below 0.5.In gravimetric methods, in which the carbon dioxide set free by acid has first to be boiled out of solution and then perfectly dried before absorption by potash, a very small weight of carbon dioxide is estimated by the gain in weight of a comparatively heavy absorption apparatus.

Description: In recent communications accounts have been given of investigations which were designed to throw light on the nature and extent of the changes which occur when a green crop is converted into silage and to furnish information regarding the factors which influence the course of the fermentation and determine in a large measure the quality of the silage.

Description: An account has been given of an investigation into the changes which occur during the preservation of the oat and tare crop in the clamp silo.The material obtained from the clamp was divisible into three types: (1) An uppermost thick layer of mouldy material. (2) “Sweet” silage from the middle layers. (3) Wet “sour” silage from the bottom layer. The spoilt material in the top layer represented approximately 19 per cent. of the whole of the crop contained in the clamp, and in addition to this, the silage was extensively spoilt round the sides of the clamp to an average depth of 12 inches. In comparing the processes of ensilage in the tower and in the clamp, it should be remembered that spoiling of this type only affects the top few inches of the material in the tower silo.The loss of dry matter in the “sour” silage layer, arising from fermentation and drainage away of juice, amounted to more than one-fifth of the dry matter of the crop originally present in the layer. This represents a much bigger loss than any previously recorded at Cambridge in similar work with tower silos. An exceptionally heavy destruction of carbohydrates further characterised the production of the “sour” silage in the clamp.The loss of dry matter in the “sweet” silage layer was much smaller and was comparable in magnitude with that occurring during the production of “green fruity” silage in tower silos.The chemical characteristics of the “sour” silage samples were investigated and were found to conform with results discussed in a previous communication, namely, the samples contained a high proportion of volatile bases to amino acids, and the volatile acids were present in appreciable excess of the non-volatile organic acids.

Description: An investigation has been described in which an attempt has been made to measure the losses of dry matter in a number of regularly spaced layers of silage contained in a tower silo, the immediate object being to determine the average loss of nutrient matter in the entire mass of material. The work was continued over the period of two silage seasons. The more important findings are summarised below:1. It is usually asserted by writers on ensilage that the attainment of such high temperatures as are necessary for the production of “sweet” silage necessarily involves an excessive loss of the dry matter of the crop as a consequence of the oxidation of carbohydrate. This statement has been shown to be erroneous both on theoretical grounds and on the grounds of actual measurements of the losses of dry matter entailed in the production of “sweet” silage. The amount of destruction of carbohydrate bears no significant relation to the temperature attained during preservation, and the factors of (a) juice drainage, (b) bacterial decomposition of carbohydrate, (c) partial spoiling by undesirable bacterial activity, as with “sour” silage, are of much greater significance in causing unduly large losses of carbohydrate.2. The results obtained in this investigation with crops containing from 26·5 to 33·9 per cent. of dry matter show that “acid brown” silage can be made in the tower silo with an average loss of dry matter equal to 5–6 per cent. of that contained in the green crop. It is further concluded that “sweet” silage, if made under good conditions, can also be produced in the tower silo with an average dry matter loss of the same order. With “green fruity” silage, the average loss under proper conditions of ensilage in tower silos is of the order of 8–9 per cent. The evidence affords strong disproof of the statement that the ensilage of green crops cannot be accomplished without large losses of nutrient matter.

Description: In some of the earlier experiments in which Bordeaux Mixture was used as a fungicide, it has happened that neither the part sprayed nor the control has suffered from disease at all; yet it has been recorded that the sprayed part has continued green for a longer period and has produced a larger crop.

Description: It has been shown that maize silage of good quality can be produced with losses of dry matter which are not necessarily much greater than those which characterise the production of oat and tare silage.Excessive drainage of juice consequent on immaturity of crop contributes materially to the total loss of dry matter.The main reason for the comparative failure of attempts in this country to produce maize silage successfully from the points of view of quality and economy lies probably in the general use of the late maturing variety, American Horse Tooth. Success will probably depend on growing a variety of maize which is able to reach a desirable stage of maturity under English conditions before being cut for the silo. Preliminary trials have indicated that the necessary qualities may be found in certain varieties like Saltzer's North Dakota, Longfellow, Compton's Early and White Cap, all of which mature at least a month before American Horse Tooth.