ALBERT

Description: The growth of barley and the phosphate concentration of the soil solution, of the soil cropped and uncropped, were examined simultaneously in pot cultures, after treatment of an acid soil deficient in phosphate, with lime with and without slag or superphosphate.Liming at the rate of half the lime requirement increased the concentration from about 0·7 p.p.m. P2O5 to about 1 p.p.m. and at the rate of twice the lime requirement to over 2 p.p.m. P205. Phosphates depressed the concentration on the lightly limed soils, and on the heavily limed had variable effects. The superphosphate-treated soils showed rather lower concentrations than the slag-treated. Cropping raised the concentration on the lightly limed treatments, but on the heavily limed reduced it on the control and had a variable effect on the phosphate treatments.

Description: 1. Herbage from pastures managed under the Intensive System of Grassland Management, and representing three to five weeks’ growth, from three centres in three seasons, was closely comparable with that obtained by other workers from “pasture cuts” at one- to three-weekly intervals from unmanured pastures, in respect of the chemical composition of its dry matter, which is, in fact, a concentrated feeding stuff of narrow nutritive ratio and low in fibre content.2. The nutritive ratio is somewhat wider in a dry than in a wet season, but the average fibre content is not markedly different.3. During the grazing season, drought or the early summer flush period produce some reduction in protein content and an increase in fibre content, with a recovery following the cessation of the drought or after the flush period respectively.

Description: The question attacked is whether soil variations are sufficiently constant from year to year to give useful corrections to the yields of experimental plots from their yields under previous uniformity trials, and the data investigated were the published results of uniformity trials carried out on two fields at Aarslev (Denmark) between 1906 and 1911. In one case the plots did tend to keep constant in their relative yields, and the precision of an experiment would be increased by nearly 150 per cent. if the regression on the mean yield in the three previous years were used: with the other field, however, the plots showed no constancy in yield (when the variation due to strips was taken out as in modern experimental methods), and consequently previous uniformity trials could give no assistance.The work described here was done whilst I was enjoying the hospitality of the Rothamsted Laboratory: it gives me much pleasure to acknowledge my great indebtedness to Dr R. A. Fisher, F.R.S., who suggested the problem, and guided my unsteady steps throughout.

Description: 1. Milk and butterfat production rise to about the sixth lactation, but beyond the fifth lactation the increase may be neglected.2. The lactation of maximum production may be taken as the fifth which corresponds to 7 years of age.3. Beyond the fifth lactation the milk and butterfat yields vary irregularly but show a downward tendency.4. The fat yield shows either a fall or only a very small increase in the second lactation.5. The fat percentage is highest in the first lactation, drops markedly in the second, remains fairly steady for a few lactations, though with a slight downward tendency, and then falls off in the higher lactations.6. Results obtained by applying correction factors for either age or lactation are quite comparable and choice in the method to be used will depend largely on the original data available.

Description: A recapitulation of the main features of the moisture distribution in an ideal soil is given in order to emphasise a point previously neglected, namely, that the changes are not in the main strictly reversible, but fall into two series corresponding to the two directions of moisture change. The cellular nature of the soil pore space imposes a quantum character on the moisture changes over a great part of the higher moisture range. The individual cell does not fill or empty by smooth reversible changes but shows two unstable stages at which filling or emptying is completed at a bound. For falling moisture the suction level is that at which a meniscus can invade a cell through one of its narrow entries, which gives a value in the neighbourhood of 12 T/r for close packing. For rising moisture the suction level is that for which water returns to the cell by the collapse of a bubble in it, giving a lower value in the neighbourhood of 6·9 T/r. A still lower value of 4·5 T/r can be reached for a particular type of distribution confined to the lower moisture range.All the above suction values are closely verified by measurements made with bronze balls and paraffin oil. A detailed exploration of the case for glistening dew and water has been made, which verifies the theory while illustrating more nearly the behaviour of an irregular soil. The two values which rule the two halves of the “hysteresis loop” for this case of natural or common packing are 6·0 T/r for falling moisture and 4·0 T/r for rising.The new considerations resolve the differences of opinion raised by R. A. Fisher. It appears that the author has throughout supported a case which belongs correctly to the falling moisture series. Fisher considered a very limited series for the rising moisture case and a hypothetical reversible series, and has been in error in so far as his treatment was regarded as exclusive.

Description: Standard English and American texts teach that liming effects a liberation of soil potash through ionic interchange. As examples we have the statement of Hall(8): “The action of lime upon potash compounds in the soil is equally marked: as the soil water carries down the dissolved calcium bicarbonate it attacks the zeolitic double silicates in the clay and some of their soluble bases, potash among them, change place with the lime and come into solution.” Similar statements, “One of the most important effects of calcium compounds is the conversion of insoluble into soluble forms of potassium…” by Van Slyke(25) and “but it also has some power to increase the solubility of phosphorus and potassium…” by Hopkins(9), have been accepted as authoritative.

Description: 1. The fungicidal properties of solutions containing sulphur in polysulphide form, viz. sodium, potassium, calcium and barium polysulphides, were tested by application to the conidial stage of Sphaerotheca Humuli growing upon young hop leaves in the greenhouse.2. Four samples of sodium polysulphide solutions, two prepared in the laboratory and two commercial products, were examined. When applied with 1 per cent. soft soap as the spreader, solutions containing 0·5 per cent. polysulphide sulphur proved fungicidal. With 0·5 per cent. gelatine as the spreader, fungicidal strength did not begin to be attained until the concentration of polysulphide sulphur reached 0·11 per cent. The results suggest that the nature of the spreader may influence the fungicidal properties of polysulphide sulphur.

Description: VI. SummaryThe conclusions of an earlier study of the yield of dressed grain from Hoos Field over the period 1852–1921 are recalled, and the method of conducting an examination of the influence of rainfall on the yield is described. The method yields a series of curves showing at any given period of the year the benefit or loss to the final yield in bushels per acre due to an additional inch of rain over the average at that period. Thirteen plots are considered, and the curves are found to fall roughly into groups corresponding to the system of manuring adopted. The main effects noted are these: (1) Excess of rain is beneficial to the barley crop for a short period in summer, and, in the case of certain plots, over the autumn and winter period. This is in contrast to the corresponding result for wheat on Broadbalk, where excess of rain was found to be beneficial only on a few plots and over a very limited period. (2) Rainfall over the six months when the barley is not in the ground is just as important as rainfall in spring and summer, and the time at which the rain falls in winter is important. Excess of rain in autumn benefits plots 1–A, 3–A and 7–2, and in winter continues to benefit 1–A and 3–A. (3) The curves for 2–O and 2–A are essentially different in character from those of the other plots, and point to the important effect of excess of winter rain in reducing the yield of the plots having phosphate but no alkali salts (i.e. no potash, soda, magnesia). (4) Excess of rain at time of sowing is harmful in all cases. (5) The curves of the “O” series (without nitrogen) are much flatter than those of the “A” series, which have a nitrogenous dressing in addition. (6) The indication of summer benefit is not inconsistent with the conclusions of Hooker that a cool summer is desirable for barley. (7) The farmyard manure plot 7–2 bears certain resemblances to the curve for the corresponding plot 2 b on Broadbalk.

Description: The fluctuation in the nitrate content of arable soils in southern Australia is of special significance in connection with the practice of bare fallowing as a preparation for wheat growing. In the wheat areas of Western Australia, South Australia, Victoria and the southern districts of New South Wales, fallowing is the recognised cultural basis for successful wheat production, and from a purely mechanical point of view the practice in the hands of the more skilful farmers has probably reached a degree of perfection which it would be difficult to surpass.

Description: (1) The maintenance requirement of Light Sussex cockerels has been found by a feeding trial and comparative slaughter method. The maintenance requirement found was 22.1 calories per sq. m. of surface per hour. The net energy of the ration fed (Sussex ground oats: whole dried milk = 13 : 3) was 1.8 calories per gm.(2) A new method of determining the surface area of birds is described.(3) The value of K in the equation area = K has been found by this method to be 9.3.