In her initial paper on “Buried Weed Seeds” (this Journal (1918), IX, 1), Dr W. E. Brenchley, in commenting on the occurrence of seeds at a depth of 9 in. below the surface of the soil, suggests that such seeds may be washed through crannies, or carried down by worms.

During the past year we have carried out at the Welsh Plant Breeding Station experiments along the lines of those of Dr Brenchley, but confining our attention to different types of grassland. We have, in the case of certain stiff clay soils, obtained seedlings from samples taken 10–14 in. beneath the surface. In samples, however, taken from peaty, hill-soil, lying beneath natural associations of Molinia, of Nardus, of Fescue-Agrostis and of Calluna, few seedlings have arisen in each case from depths lower than 3 in. The latter soils are remarkable for containing extremely few earthworms, and the suggestion was provided that these animals are instrumental to a quite considerable degree in burying seeds deeply in the ground.

1. Palestine Pan, “Nasas”, is found in the coastal plain among red sandy soils and its presence is shown by one or more impermeable layers in the depth.

2. Red sandy soil in which “Nasas” is present is an unstable soil system which is liable to the process of degradation.

3. Observations made on red sandy soil in relation to relief show the transportation of colloidal clay, A1(OH)3 and Fe(OH)3, along the slope and into the depth.

4. The ratio of A1(OH)3 to Fe(OH)3 shows a relatively large downward transportation of A1(OH)3. This increase of A1(OH)3 in the lower layers of the soil is the chief factor in the formation of the impermeable layers.

Two series of trials have been carried out to compare the digestibility of fresh grass with the material obtained by drying grass, from the same source and cut at the same time, in a band drier by heated air at an inlet temperature of 200° C.

This process has not affected the digestibility of the various constituents with the possible exception of the crude protein which is slightly depressed.

In the second series of trials a drier operating with air at an inlet temperature of 600° C. was also used. In this drier a depression of the digestibility of the constituents of the grass was noted. This was particularly so in the case of the protein which was depressed to a very marked degree.

It would therefore appear that although the use of the higher temperature increases the output of the drier, it adversely affects the digestibility of the final product.

1. Dried cell substance of various micro-organisms—nine fungi, one actinomycetes, two bacteria—were subjected to decomposition in soil and sand. In neutral garden soil, the addition of microbial substance gave rise to a more or less abundant, but always temporary, development of bacteria and actinomycetes; the latter group of organisms was often stimulated to a very conspicuous degree.

2. The development of micro-organisms was accompanied by a more or less abundant production of nitrate. After 60 days 19–61 per cent. of the added N had been nitrified, and after 120 days the proportion had in most cases not increased very materially.

1. No beneficial effect on the growth of barley or mustard on two types of soil was obtained by the addition of quantities of copper sulphate ranging up to 4 per cent. of the total artificial fertilisers applied. Experiments on English acid and alkaline peats with barley, rye and turnips failed to show the striking results obtained by American workers on saw-grass peat in the Everglades of Florida.

2. Increased fineness of grinding of basic slag in some cases brings about a certain reduction of crop. This may be due to the presence of vanadium in such slags, as experiments show that this element is definitely toxic to plant growth.

3. Lithium compounds are much less toxic than copper to the growth of barley. In some water culture experiments a suggestion of stimulation was obtained with very dilute concentrations of lithium chloride in the presence of nutrient salts, paralleling Voelcker's results with other lithium compounds in soil. Buckwheat is much more sensitive to the toxic action of lithium, and also shows no stimulation with any concentration.

It is important to bear in mind that the investigation outlined in this paper was designed primarily to test the effect of periodic applications of sulphate of ammonia on the yield and composition of good permanent pasture, well supplied with reserves of lime, potash and phosphate. The results have no bearing on the possible effect of manurial treatment on the yield and composition of inferior types of pasturage. The present account embraces the findings of the first two seasons of experiment, namely, 1929 (characterised by droughty conditions) and 1930 (season of ample rainfall).

Hay of excellent quality and high digestibility has been made by a process of artificial drying in which a current of warm air is blown through the grass in a stack. The air is heated by a system of hot-water pipes round which the stack is built.

The resultant product was of much greater feeding value than good meadow hay or seeds hay and was made at a season of the year when hay-making conditions were poor.

The economics of the process have not been worked out.

1. Depreciation of carcass weight during dressing procedure was greater in male than in female rabbits of similar age.

2. The composition of rabbit flesh was found to be markedly different in males and females.

3. The greatest difference was in the fat content. Females having approximately 4 per cent, more fat than males in the “young” group, and approximately 6 per cent, more in the “adult” group.

The authors wish to thank Prof. Raymond T. Parkhurst for his assistance during the experiment, and Dr C. Crowther for help with the manuscript.

The limitations of the “constant” saturation capacity as a factor in the characterisation of types of soils, rather than individual soils, are discussed. An attempt has been made to overcome these limitations by distinguishing between the contributions made to saturation capacity by the organic and inorganic colloidal components of three widely different tropical soil types.

1. Numerical evidence is given which shows that saturation capacity is very closely related to the content of clay and organic matter of soil (irrespective of the proportions in which they are present), but not to the fine silt fraction. Nevertheless, the correlation between saturation capacity and (a) organic matter, and (b) clay, is significantly greater for the tropical type containing the smallest amounts of these components than for the type containing the largest amounts.

1. The results of an investigation into the yield and composition of pasture grass from certain of the Tree Field plots at Cockle Park have been described. Samples were taken from randomised cutting areas, at intervals of 14 days, during a season of 22 weeks. The experiment was so designed as to admit of the application of statistical treatment to the results.

2. The differences between the mean yields of dry matter from plots under varying manurial treatment could not be regarded as significant, and it is noteworthy that the control plot has not proved inferior to any other. The yields showed marked and significant seasonal variation, the occasion mean reaching its highest values in early summer and in autumn. The correlation of dry matter with rainfall, sunshine and temperature data yielded no significant results.

In collaboration with my assistants, O. Ulvesli, M. Husby and K. Breirem, I have been working for the past 7–8 years with problems as to the vitamin requirement of calves, young cattle and growing pigs. The purpose of my investigations was to discover, if possible, the practical significance of the vitamin hypothesis in its bearing on agricultural practice. It is a well-known fact that the indiscriminate application to farm animals of results obtained with small laboratory animals is not warranted—the requirements of each species of animals must be tested separately. As a starting point it was necessary, therefore, to consider first, whether or not farm animals exhibit the same susceptibility to vitamin deficiency as the small laboratory animals, and secondly, whether or not our commonly used feeding stuffs for farm stock contain enough vitamins to avoid any deficiency symptoms.

1. The mineral content of pasture as grazed under the Intensive System of Grassland Management has been examined. The pasture samples were collected from two centres in 1927 and from one centre in 1929. Magnesium, manganese, iron, sulphur and chlorine were determined in addition to the more common elements.

2. The mineral content of intensive pasture is equal to that of the best type of pasture produced by other systems of management, and superior to that of average good cultivated pasture in Great Britain.

3. The seasonal variations of the soluble ash, potash, soda and phosphoric acid depend principally on the climatic conditions.

4. The effect of drought at one centre has been to lower the percentages of soluble ash, potash and phosphoric acid.

5. Correlations exist between nitrogen and phosphoric acid, and soluble ash and potash. There is no evidence of further correlations between the constituents.

An experiment was carried out in 1929 and 1930 to obtain a measure of the effects of nitrogenous fertilisers used in combination with rotational grazing, on grass adequately supplied with phosphates, potash and calcium. A comparison of the two years has shown that the magnitude of these effects is governed by climatic conditions, and in the absence of a sufficient supply of moisture the increase in the quantity of herbage produced is reduced.

1. Hard winter wheat was grown under natural conditions from September, 1930, to June, 1931 (both inclusive). The ash, oils and fats (ether extract), moisture, sugar, starch, hemicelluloses, total nitrogen and the growth of the plants were determined every fortnight. Grains were also analysed twice during their development.

2. The data (for the plants) seem to indicate that there was less moisture during early growth (in winter) and at the time of maturity.

An account has been given of the lipin, phytin and inorganic phosphorus, and of the protein and non-protein nitrogen present in the wheat plant, from seven weeks before ear emergence until the crop was harvested

The percentages and amounts of phosphorus and nitrogen so combined, together with their distribution between straw and ear, have been discussed.

Relationships between phytin phosphorus and protein nitrogen, and between lipin phosphorus and non-protein nitrogen, have been indicated.

The decomposition of the organic matter of the soil by means of hydrogen peroxide is shown to be a function of the hydrogen-ion concentration of the soil, alkaline soils permitting of a very low degree of oxidation, while with acid soils up to 90 per cent, of the organic matter is destroyed.

The results obtained with a range of soils suggest that a portion of the organic matter is oxidised irrespective of the soil reaction, while the oxidation of the remainder is a definite function of the hydrogen-ion concentration, the relation being expressed by the equation

The proportion of the organic matter oxidised further appears to be a definite function of the clay content of the soil. Alkaline soils containing free manganese dioxide also show small losses.

The investigations described in this paper show that:

1. The nitrogen contained in purified preparations of humic acid obtained from Rothamsted soils cannot be eliminated by methods which would be expected to remove simple nitrogenous impurities.

2. The distribution of the nitrogen in the products of hydrolysis of these preparations of humic acid by hydrochloric acid, as determined by the Van Slyke method, is similar to that found in the hydrolysates of proteins.

3. A mixture of egg albumen and artificial humic acid from lignin resembles soil humic acid in regard to the effect of various methods of treatment on its nitrogen content. In both cases, the greater part of the nitrogen is not removed by the action of proteoclastic enzymes.

Unreplicated dry-matter estimations on cores of swede are subject to errors caused by deflection of the borer from an intended alignment, and also to asymmetric concentrations of solids. A series of experiments was carried out to determine the extent of error likely to occur through deflections from diagonal and horizontal coring alignments. The coefficient of variability was estimated as about 1 per cent. of the drymatter value for either method. The relationship in dry-matter value of horizontal cores, diagonal cores and whole bulbs was found to be approximately 95:97: 100 respectively. There is little difference in accuracy between the coring methods; in practice the horizontal core is capable of more facile application.

The results so far recorded in this series of investigations are discussed in their bearing on the hypothesis according to which the humic matter of soil is derived from lignin.

This hypothesis is supported, but since the artificial product prepared from lignin is nitrogen-free, whereas the natural product contains nitrogen, further progress in the elucidation of the nature and origin of humic matter is dependent on a study of the part played by nitrogen in the formation of humic matter, and the form in which it occurs.

The effect of rainfall on the wheat crop grown on Broadbalk has been investigated, special attention being paid to the time of application of the nitrogenous manures.

In the years 1854–77, when plots were manured solely in the autumn, the average decrease in yield caused by each additional inch of rain is greater than the average decrease from 1854–1918. The difference in this case cannot be ascribed to the change in manurial treatment.

The period of 24 years was too short to allow seasonal variation in the effect of rain to appear, as it was only possible to compare such seasonal variation with that of 1854–1918 in the case of one plot. In this case it was observed that summer rainfall was more detrimental to autumn-dressed than to spring-dressed plots; this result was confirmed by studies of the effect of rain on the difference in yield of two plots which differed only in the time of application of their manures.