1. The interaction of physical conditions of the soil and the establishment of plant together with its subsequent growth and yield have been studied for wheat and swedes on a variable piece of land, maintained as a uniformity trial.

2. Ploughing draught was taken as a criterion of the physical condition of the soil and various simple measurements on the crop were made from time to time during growth.

3. The establishment of wheat showed substantial negative correlations with ploughing draught but the correlations between ploughing draught and the performance of the plant diminished as growth progressed. This was shown to be the result of the overwhelming importance of the spacing factor operating beneficially on plots where the plant was abnormally poor. The effect of this factor is traced step by step.

4. Swedes differing from wheat in almost every detail of cultivation and growth, cycle showed no correlation between soil conditions and germination or between the various growth stages and physical soil conditions. The highest significant correlation was between the number of roots per plot after singling and ploughing draught and an explanation of this is given.

5. There was a significant but only moderate correlation between the yields of the two crops.

1. Considerable differences were found in the specific conductivities of different soils at any one time of the year, and considerable differences in any one soil at different times of the year, the specific conductivities being highest in March and lowest in June and July. Hence it is only possible to compare different soils when samples of these soils are taken at the same time of the year.

2. A relation has been found between the specific conductivities of the soil extracts and the mean weights of lint per plant per row in the case of 2 strains of Ishan cotton. Other data are presented showing that the specific conductivity of a 1 to 5 soil extract is an index of the fertility of the soil.

3. It has been found that the specific conductivity of a soil decreases under continuous cultivation. There is evidence that the rate of solution also decreases under the same condition.

In an earlier communication on this subject(1), the writers arrived at the conclusion that the main reason for the comparative failure of attempts to grow maize as a silage crop in this country was due in large measure to the general use of the late maturing variety, American Horse Tooth. It was predicted that success would probably depend on discovering a variety of maize which is able to reach the desirable stage of maturity under English conditions before being cut for the silo. Preliminary trials had indicated that the necessary qualities might 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.

Certain heavy ferruginous soils do not respond to the usual preliminary treatment with hydrogen peroxide for mechanical analysis by the pipette method.

A method of preliminary treatment is described, involving the use of ammoniacal hydrogen peroxide and repeated gentle rubbing with a rubber pestle which appears to give a satisfactory dispersion with such soils.

The results are not affected by mechanical shaking, which may therefore be omitted.

In the course of investigations into the cause of an obscure pathological condition of the tea bush, it became necessary to make pH determinations of certain soils. Electrometric apparatus and a suitable centrifuge for clearing the solutions were not available. Considerable difficulty was experienced in making the determinations with accuracy by indicator methods owing to two causes. First, the turbidity of the soil solutions made comparison with standard buffer solutions somewhat difficult; secondly, the colours developed in the soil and buffer solutions with some indicators were different in hue, as distinct from shade or tint. This rendered exact matching quite impossible. The latter difficulties also arose when the drop ratio method was used instead of standard buffer solutions. The errors resulting from these causes were believed to be unduly large, and it was felt that greater accuracy would be attained if these difficulties could be overcome.

This paper describes a statistical analysis of the records collected by the Norfolk Milk Recording Society (3918 lactations), comparing the results with those obtained from the records of the Penrith M.R.S. (already published).

As in the case of Penrith, autumn calvers were found to average more milk in a lactation than spring calvers, but the best months of calving were two months later—i.e. October to February instead of August to December; this is because in the case of Norfolk, yields are maintained well throughout the winter, whereas they fall off very rapidly in the Penrith district from February to April, and if this bad period comes early in the lactation a low yield results. The yield falls off, in both districts, very rapidly during summer (after the flush of grass in spring) and particularly during the two periods June-July and September-October; the average rates at which the yield declines during different calendar months, appears to provide the explanation of the variation in yield according to the month of calving. Seasonal variations appear to be nutritional, rather than meteorological, in nature, and it seems probable that with more knowledge of feeding and management they should be largely eliminated; the greatest scope for improvement lies in summer, when it is suggested arrangements should be made for a supply of catch-crops for feeding green, and this supplementing of the grass should begin much earlier in the year—i.e. beginning of June in normal seasons—than is generally believed.

1. A procedure is described for evaluating an “index of texture” (I.T.), based on determinations of moisture contents at the point of stickiness (P), and of sand contents (S) of soil samples.

2. The procedure is simple, and allows of a rapid laboratory examination of a great number of spot samples, so that detailed texture maps can readily be constructed.

3. Employed in conjunction with soil-reaction maps, the texture maps form a useful basis for detailed investigations of soil genesis and soil fertility.

1. The value of the knowledge of the saturation capacity of a soil as an aid in its characterisation and classification is briefly stated.

2. A short account is given of the more important methods in use for determination of saturation capacity.

3. The theory underlying the method of Page and Williams, and the possible defects of the method are discussed.

4. The results of an investigation of this method lead to the following conclusions:

(a) Leaching the mixture of soil and calcium carbonate to 2 litres is in sufficient to displace from the soil all its exchangeable bases.

(b) In view of this, it is recommended that 3 litres or more of filtrate be obtained, or preferably, the amount of soil employed be reduced to 10 grm.

(c) The leaching solution remains in contact with the soil mixture for a period adequate for the normal sodium chloride solution to be saturated with calcium carbonate.

(d) The difference in the amount of calcium, derived by solution from the carbonate, in the first and second litres of filtrate, is sufficiently small to be neglected.

(e) The tardiness with which the reaction proceeds to completion is probably due to the difficulty experienced in displacing the final amounts of adsorbed ions, rather than to the presence of calcium ions in the leaching solution.

(f) The incompleteness of the reaction renders the method of Hissink inaccurate for the calculation of the saturation capacity.

(g) The variation in the character of the colloidal material of soils i s to some extent reflected in the value of the ratio of the calcium passing into solution through exchange reactions in the second litre, to that dissolved in this manner by the total volume of filtrate.

The present investigation was undertaken with the object of ascertaining the effect of cutting at fortnightly instead of weekly intervals on the yield of pastures, and on the composition, digestibility and nutritive value of the herbage.

The main trial was carried out on the 1925 light-land pasture. The plot was divided into 14 sub-plots, and one sub-plot was mown per day. The whole plot, therefore, was cut over once per fortnight during the season. The results in respect of yield, composition and nutritive value were compared with corresponding results obtained on the same pasture plot under a system of weekly cuts during 1925.

A second trial was carried out on sub-plots 2 and 3 of the 1926 heavy-land pasture, one sub-plot being cut weekly and the other fort-nightly. The work in this case was restricted to securing comparative data in respect of yield and composition of herbage.

The results from both trials lead to the conclusion that the differences in chemical composition, both organic and inorganic, between pasture grass cut at weekly and fortnightly intervals are inconsiderable. The dry matter of the fortnightly-cut grass is extremely rich in crude protein and contains, in comparison with grass cut at the hay stage of maturity, a low percentage of crude fibre. Moreover, these characteristics are retained, by systematic cutting at fortnightly intervals, over the entire season.

The results of the digestion trials justify the conclusion that the dry matter of the pasture herbage grown under a system of fortnightly cutting is a protein concentrate equal in digestibility and nutritive value to that obtained by weekly cutting. There is no significant running off in respect of composition and feeding value during the second week of growth. At the end of a fortnight the herbage still consists of the same immature, non-lignified. tissue as it was at the end of a week's growth.

The fact that the findings of various workers on the influence of weather on yield in oats are seldom in agreement on all essential points suggests that the requirements of the crop varies from province to province, and warrants investigation within regions of relatively narrow compass.

In any field of corn the population-density or number of plants per unit length of row is very fluctuating. Accidental circumstances may result in considerable stretches being empty or thinly populated. Quite apart from this, the population of successive short lengths is sharply and characteristically inconstant. Where plants are few tillering is profuse and there is thus a tendency towards constancy in yield per unit length of row. Specific ascertainment has, in earlier experiments, suggested that the tendency is by no means marked. In consequence fluctuation of population-density in the sense here used, reduces yield in typical field crop substantially below the potential maximum appropriate to the soil and other circumstances. From short lengths of row, low in plant-population, yields are low. In aggregate these sparsely populated lengths are a feature of considerable economic importance.

1. When a peat, as obtained from the bog, is dried, considerable changes occur in the amount of ammoniacal nitrogen removable by distillation with magnesia under reduced pressure.

2. Removal of water causes a relative increase in the amount of ammonia extractable by water. This is due to a reduction in the absorptive colloidal properties of the peat.

3. A partial recovery in the absorptive power takes place on prolonged contact with water.

1. A historical review of the dye adsorption method for the estimation of soil colloids is presented, and the method is criticised chiefly from the point of view of the isoelectric theory.

2. A procedure for the detection of hydrous alumina in soils is described, involving the demonstration of the isoelectrio point of hydrous alumina by means of preferential dye adsorption in suspensions of various pH values.

3. Satisfactory results were obtained with a mixture of acidic Biebrich Scarlet and basic Iodine Green. The former is adsorbed by hydrous alumina only on the acid side of its isoelectric point, and the latter only on the alkaline side.

4. The characteristics of an ideal dye for use in studies such as those described are tabulated.

5. The applicability of the mixture of dye-stuffs finally selected is demonstrated for a series of soils of varying basic ratio, and including examples of lateritic soils and clays.