Biological & Medical Serials : _ LAWES AGRICULTURAL TRUST Rothamsted Experimental Station : Harpenden | REPORT 1915-17 with the Supplement to the “Guide to the Experimental Plots” containing The Yields per Acre, etc. NOV 14 1918 we Or 5 + is : A HARPENDEN BRAS PRINTED BY D. J. JEFFERY, VAUGHAN ROAD 1918 1 brings f 7 ¥ MB orice) ayer "SLYSBH ‘'NSQN3dyuyvH ‘NOILVLS IWLNAWIYSdxXy GSALSWVHLOY YR EE Mypryl of jen C4 IAG Ces OSLO eae aT tag cy fo pyrorns olpymouyon Typtny ‘ISNY | IWYNLINDIEOYW SAMV7] LAWES AGRICULTURAL TRUST Rothamsted Experimental Station Harpenden REPORT 1915-17 with the Supplement to the “Guide to the Experimental Plots” The Yields per Acre, ete. Telegrams Telephone Station Laboratory, Harpenden No. 21 Harpenden (Midland HARPENDEN | PRINTED BY D. J. JEFFERY. VAUGHAN ROAD I 1918 RMT, ani rn og OLS i! aT wl aril : iii tis me = 2 “aie iti eas i “a a | ae weal am: ae i THE NEW ROTHAMSTED LABORATORIES, ERECTED 1914-1916 ———— Contents Page Illustration; New Laboratory ... a stat sf a ie eZ Experimental Station Staff . . a He hee ee ae 4 Introduction a a oS ire ae 5 aa sas 5 Report of the Three Years’ Work, 1915-17 ap A, 2 wf The Library Ase a ov Be a oe ee fan ess Report on Farm and Experimental Plots: Season 1914-15, 1915-16, 1916-17 aah Wks eas Boe ae ee ee 15 Papers published : SoiL PROBLEMS: Atmosphere of the Soil — Biochemical Changes in the Soil—Dissolved Oxygen in Rainwater—Soil Protozoa—Organic Residues and Nitrogen Fixation—Bacterio- Toxins in Soil—Dilute Acids and Phosphorus Compounds of the Soil—Adsorption by Soil—Loss of Phosphoric Acid dur- ing fusion with Ammonium Chloride—Lime requirements ol Soils—Soluble Humus and Soil Productiveness ae ee 22 FARMYARD MANURE: Making and Storing of Farmyard Manure—Fixation of Nitrogen in Faces—House Flies and Manure Heaps oN) are ae Lop aaa ee p20 26 PLANT NUTRITION PROBLEMS: Formation and Translocation of Carbohydrates in Plants—Enzymes in Carbohydrate Analy- sis—Organic Plant Poisons—Concentration of Nutrient Solu- tion and Plant Growth—Recolonisation of Land gone out of Cultivation—Effect of Weeds upon Cereal Crops—Buried Weed Seeds ahs i bas ay. doe eas Eo TECHNICAL PAPERS: West Country Grasslands— Weeds on Arable Land—Yield of Second-rate Arable and Pasture Land —Crops without Potash Manure—Two White Straw Crops in Succession—Loss of Nitrate from Arable Soils—Soil An- alysis—Increased Crop Production—Chalking—Army Stable Manure—Humogen—Dried and Degreased Sewage Sludge— Charcoal and Plant Growth pe ae: ae ae oe AO PAPERS SUMMARISING RECENT PROGRESS IN AGRICUL- TURAL INVESTIGATIONS... i Ee . es ae 48 BOOKS PUBLISHED ... see nee Pen ne a ee 48 Enquir’es Undertaken at Government Request... ahs ... 49 Tables of Field Trials, etc. ... a hoe ee re eS Trustees and Committee of Management ae a He. CLO Members of Council of the Incorporated Society for Ex- tending the Rothamsted Experiments in Agricultural Science “a3 see ie nf a i* ue SRE oy AO Subscribers and Donors ae ee tae an Pe: i, RAO Experimental Station Staff Director: -E. ]- RUSSELL, DiSe,, FulcS: Lawes & Gilbert Laboratory Chemist.622. E. HORTON AB Se. Rupert Guinness Research Chemist 1D Bee RICHARDS, Be Se.,0melee- Chemist ... oe bas Bd ; soc, OE MATTHEWS a J. DAIisH; Bisse, 2G. wn eC; Saar W. Be Randall Resetrch Biologist Mrs. D. J. MATTHEWws, M.Sc. Assistant Chemist ae aan E. M. CROWTHER, B.Sc. Field Superintendent... et = mmtee Ore 2 Chemical and General designs: A. OGGLESBY, B. WESTON, A. BOWDEN 3) Laboratory Assistants ... “W. GAME, “F. SEABROOK, N. JONES James Mason Laboratory Bacteriologist ie oe ay H. B. HUTCHINSON, Ph.D. Assistant Bacteriologist ... a a. Wo, BEWEEYb.5c- Laboratory Assistant ha “as ... F. RICHARDSON Soil Laboratory Chemist... =a ¥ . “A. APPLEYARD, M.Se: i vee ne ae ao TATTERSEIBE D, B.Sc eh ve: Goldsmith’s Company’s Physicist = “ee IN KEEN, Bescs Botanical Laboratory Botanist ... ier WINIFRED E. BRENCHEBY, Disc. e = Assistant Botanist . a ... MARY Dy Gilby ise. - s fie ee VIOLET G. JACKSON, B.Sc. Laboratory Assistants... “GRACE BASSIL, NORA PEARCE Protozoological Laboratory Protozoologist ... a rat LETTICE M. CRUMP, M.Sc. Entomologist ao = .. A. W. RYMER ROBERTS, MLA. Library Weibranian’ 4. oti a: = ae HELEN ADAM, B.Sc. Assistant “7 ae. wae sa KATHLEEN CUMBERLAND Farm Manager ... eae Bo S. J. K. EAMES Acting Manager anid Bookkeeper cx Mrs. S. J. K. EAMES Secretarial Staff Secretary ... se ene ie Ye, RUTH GIMINGHAM Private Secretary : ee “GERTRUDE BATES Acting Private Sane ars Be CH ARLOTTE F. S. JOHNSON Junior Clerks Bc a eo. . = “C. PEARCE, EvA TIMSON General Assistant and Caretaker set =P \W. PEARCE General Assistant ie ae ber ne ‘G. LAWRENCE * On War Service ss - Fal hed 5 : iJ a on INTRODUCTION John Bennet Lawes was the founder of the Rothamsted Experi- mental Station. He began experiments with various manurial substances, first with plants in pots and then in the field, soon after entering into possession of the estate at Rothamsted in 1834. More systematic ficld experiments were begun in 1843; the services of Joseph Henry Gilbert were then obtained as Director, thus starting the long association which only terminated with the death of Lawes in 1900, followed by that of Gilbert in 1901. The Rothamsted Experimental Station has never been connected with any external organisation, but was long maintained entirely at the cost of the late Sir John Lawes. In 1889 he instituted a Trust for the continuance of the investigations, setting apart for that purpose the old laboratory which had been built by public subscription and presented to him in 1855, certain areas of land on which the experi- mental plots were situated, and a Trust Fund of £100,000. By the provision of the Trust Deed the management 1s vested 1 a Committee nominated by the Royal Society (four persons), the Royal Agricultural Society (two persons), the Chemical and the Linnean Societies (one each), together with the owner of Rothamsted. Mr. A. D. Hall (now Sir A. Daniel Hall) was appointed Director in rgo2 and held the position till he resigned in 1912, when the present Director, Dr. E. J. Russell, was appointed. Mr. Hall brought about great developments, re-organising the work, increasing the staff. and considerably extending the buildings and laboratories. In 1906 Mr. J. F. Mason, M.P., presented the Committee with {1,000 for the building and equipment of the ‘“ James Mason” Bacteriological Laboratory, together with an annual grant towards its maintenance. In 1907 the Goldsmiths’ Company made a grant of £10,000, the income of which is devoted exclusively to the investigation of the soil. The Permanent Nitrate Committee also made a grant of £2,000 to the endowment. Jn 1913 Lady Gilbert presented the library of the late Sin, }. Henry Gilbert. Since 1913 the Hon. Rupert Guinness has provided funds to maintain a special research chemist, and in 1917 Mr. W. B. Randall similarly made provision for a research holonce The collection of smaller donations and annual ‘subscriptions is the work of the Society for extending the Rothamsted Experiments which was founded in 1904. . During the year 1911 a scheme for the encouragement of agri- cultural research was issued by the Board of Agriculture, funds being provided by the Development Commission; under this scheme a certain number of institutes were established for fundamental researches in agriculture each dealing with one great branch of the subject. The Rothamsted Experimental Station is recognised as the Institute for dealing with Soil and Plant Nutrition Problems. In accordance with this scheme an annual grant of £2,500 was made, which has since been increased to £2,850. Besides the regular staff, a number of post graduate workers and holders of scholarships carry out their investigations at Rothamsted, 6 and investigators from other institutions periodically spend a certain amount of time in the laboratories studying analytical methods or ways of getting over difficulties that have arisen in the course of their work. These developments necessitated a considerable extension of the laboratory and of the farm. ‘The first step consisted in taking over 230 acres of land in 1911 on a 77 years’ lease, which, with the Trust land, provided a self-contained farm capable of being worked with great advantage to the experiments. Suitable farm buildings and cottages were erected in 1913. A new wing was also added to the laboratory, and this was opened on June 27th, 1913, by the Rt. Hon. Walter Runciman, M.P., then President of the Board of Agriculture. In 1914 the old lahacroe which had for some time revealed certain structural defects, was taken down and a new laboratory was begun, to commemorate the centenary of the birth of Sir J. B. Lawes in 1814 and of Sir J. H. Gilbert in 1817. Altogether these improve- ments cost about £26,000, of which £10,000 was given in grants from the Development Fund and £10,000 was collected by public subscription, £6,500 being obtained as the Lawes and Gilbert Centenary Fund in 1914-106. The field experiments, which began in 1843, have on some of the plots been continued without break or alteration up to the present day ; on Broadbalk Wheat Field certain rearrangements were made in 1852, in which year also the Barley experiments on Hoos Field began. The leguminous crops on Hoos Field were started in 1848. The experiments on roots have been continued on the same field since 1843, and on the same plan since 1856. The Park grass plots began in 1856, and the rotation experiments in 1848. It is impossible to exaggerate the importance of continuing the experimental plots at Rothamsted without any change, as nowhere else in the world have such extensive data been collected for studying the effect of season and manuring upon yield and quality of crop, and for watching the progressive changes which are going on in the soil. Year by year the plots are found to throw light upon new problems in Agricultural Science ; in all directions they continue to provide material for investigations upon points which were not contemplated in the original design of the experiments, so that it is impossible to foresee when and how they will not become useful and provide indis- pensable material for the solution of problems undreamt of at the present time. The maintenance of the programme, however, throws a heavy burden on the Experimental Station. There are 210 plots, and every year 243 samples have to be taken with proper precautions and put into store for future reference. In addition, many analytical determinations are made. Complete soil samples are periodically taken for analysis, to enable a comparison to be instituted with samples taken earlier, and thus to study the soil changes that have gone on during the period. Botanical analysis of the grass plots are also made. It should be remembered that the object of the Rothamsted Experiments is to study the soil and the crop, and only indirectly to find the most paying method of manuring ; hence neither the nature nor the quantities of material applied are to be taken as indicating the manures which should be used in practice. f 4 5 F ~ REPORT ON THE WORK OF THE THREE YEARS, 1915, 1916, 1917. HE work of the Station and its personnel have been considerably modified by the advent of the War. At the outset the Staff was rapidly depleted, two-thirds of its members joining the fighting forces or undertaking Government work for which their experience at Rothamsted specially qualified them. ‘Two of those who joined the Army have lost their lives, C. H. Martin and K. R. Lewin, both men of great intellectual promise and of much charm of character. Of those who remained four of the oldest died, N. H. J. Miller and G. ‘I’. Dunkley with tragic suddenness, W. Freeman and W. Wilson after long illness. Of the band of workers collected and trained by Lawes and Gilbert, who had also faithfully served under Mr. Hall, only two are now left, E. Grey and A. Ogglesby. From the outset the depleted Staff was called upon to undertake a considerable amount of work for the Board of Agriculture and subsequently for the Ministry of Munitions. The work was further increased as the food problem became more urgent. When the Board of Agriculture was enlarged in 1917 the newly formed Food Production Department asked the Committee for a definite portion of the time of the Director, a request to which the Committee acceded. Despite changes in the Staff and in the conditions the investiga- tions have been continued ; women have come in to take the places of the workers who are gone, and the more important lines of enquiry are being pursued. ‘The programme of work is naturally undergoing modifications. As the shifting agricultural conditions bring new problems into prominence, these are brought as far as possible into the scope of our investigations ; the danger, always present, that experi- mental work may become artificial and remote from practice has been met by setting up an ordinary farm of 230 acres in addition to the experimental area, and more recently by the connection estab lished with the Food Production Department, which brings in new and important problems that require study. For many years past the purpose underlyi ing much of the Rotham- sted work has been to restore the tradition of ood farming and of good country life. By common consent Great Britain led the Way in farming practice in the fifties, *sixties and ’seventies of the last century ; iravellers came to see our methods and went home to copy them. ‘This fine position was lost in the ’eighties and ‘nineties ; the falling prices of that period were met in this country by lowering our farming methods. In Belgium, Holland, Denmark, and Germany, on the other hand, the situation was met by intensifying the methods, with the result that they excelled us and built up an intensive system suited to modern conditions. It is much to the credit of British agriculturists that they were able to exist through the bad times at all. Fortunately our error was realised early in this century, and the more vigorous of the younger race of farmers have endeavoured to retrieve the situation. The work of the Rothamsted Experimental Station is mainly concerned with the investigation of the soil and the growing crop. At the present time the enquiries fall naturally into four groups— the economical use of manures, the ploughing up of grassland, the control of soil organisms, and the nutrition of plants. 1. THE ECONOMICAL USE OF MANURES AND FERTILISERS. One of the urgent needs of the present time is to make the most economical use possible of all manures and fertilisers. Farmyard manure is by far the most important of these, the quantity used on the land exceeding many times in weight and value all other fertilisers. It is estimated that 37,000,000 tons per annum are made in the United Kingdom, of a value of not less than {11,000,000 ; all other fertilisers put together did not before the war much exceed £4,500,000 in value and 1,000,000 tons in weight. It has long been known that farmyard manure suffers serious loss as handled on an ordinary farm; good esiimates show that at least half its nitrogen, its most useful con- stituent, is usually wasted. Through the generosity of Capt. the Hon. Rupert Guinness it has been possible to investigate the nature of the loss and show how it arises. Two causes were found to operate. exposure to weather and the penetration of air into the heap; both led to considerable loss, and when both act together, as they do on so many farms, especially dairy farms, the aggregate loss is very consider- able. Methods of dealing with the loss: “due to exposure are easily suggested, and when carried out they have led to considerable en- hancement of crop-producing power. The exclusion of air is more difficult and would involve a new method of storage. It is found that manure kept in complete absence of airat a temperature of about 26°C. not only loses no nitrogen but positively gains in other ways, notably in that its complex nitrogenous constituents are broken down into highly valuable ammonia. Unfortunately these ideal conditions are not attained in ordinary practice, and Mr. Richards is attempting to find a way of realising them; this work is being carried out on the Home Farm at Hoebridge, W oking, where Captain Guinness has provided all necessary facilities. At the outset the investigation is being confined to the simplest case, the conservation of quid manure ; afterwards we hope to pass to the more difficult problem of whole manure. In the past farmyard manure has been studied mainly as a source of nitrogen, but investigations made at Rothamsted and elsewhere show that this is too narrow a view of the problem and that other organic constituents may also play an important part. A considerable part of the manure heap is made up of straw, which, as farmers have long recognised. must undergo a certain amount of decomposition before the best results can be obtained. Our experi- ments show that the unchanged straw goes far to neutralise the benefits of the other components and in extreme cases it may actually depress the crop. Certain changes in the cellulose and other carbo- hydrate constituents are essential, and experiments are in hand to ascertain what these are and how they are brought about. Work in this direction is carried out by Dr. “Hutchinson and Mr. Richards. Dr. Hutchinson has shown that the decomposition of cellulose is effected by an organism of peculiar morphological character- istics, the knowledge of which has enabled him to account for some of the discrepancies in previous work. The conditions and nature of the action are under investigation. For the moment, however, the centre of interest is the connection of this decomposition with another change of supreme agricultural importance. It is well known that certain organisms living free in the soil and quite distinct’ from those associated with the nodules on clover roots, have the power of assimilating gaseous nitrogen from the atmosphere, but as this process requires considerable energy it is essential to provide the organism with easily oxidisable material. Straw contains certain substances and on decomposition yields others which are eminently suitable for this purpose. It is possible to start with straw, soil, chalk and the proper organisms, and with these raw materials alone to secure both the decomposition of cellulose and the fixation of nitrogen, so that a manure is finally obtained which contains considerably more nitrogen than the original components, the excess being derived from the atmosphere. So far this has been done only as a laboratory experiment on the small scale. Before we can say whether the process be feasible on the large scale, it is necessary clearly to define the conditions. The problem is also being attacked in another way. Mr. Richards has shown that horse faces contain something suitable for the process of nitrogen fixation. Moreover he has obtained from the feeces an organism which works in conjunction with the nitrogen fixers ; hence, like Dr. Hutchinson, he can start with straw and the appropriate organisms, and by a process which is simple in principle obtain a considerable enrichment of the manure in nitrogen. The two investigations are now converging and both are being tested on the semi-practical scale. It is too soon to express any opinion as to their practicability on a large scale, but if the ploughing up of grass land continues the country will be faced with a large production of straw for which an outlet must be found ; considerable quantities of bulky organic manure will also be required. If the nitrogen fixation plan prove feasible in practice it will afford a con- venient solution of both problems. Besides making the most economical use of farmyard manure, it is equally necessary to use the artificials and other fertilisers to the best advantage. A considerable amount of information on this subject has been obtained at various times both at Rothamsted and elsewhere ; this has been collected and issued in a form convenient for farmers in a book written by the Director entitled ‘‘ Manuring for Higher Crop Production.” Work on the effect of liming, to which reference has been made in the previous Report, has been continued. Il. THE BREAKING UP OF GRASSLAND. The second group of problems under investigation arises out of the breaking up of grassland. When, in 1915, it became evident that this policy must ultimately be adopted, a grass field was broken up and sown with various experimental erops. These suffered considerably from the depredations of birds, so that the experiment lost much of its quantitative value ; the hedges and trees, which had given a charm to the landscape and afforded shelter to the beasts while the land was used for grazing, became a pestilential harbour for sparrows and wood pigeons as soon as it was used for arable purposes ; in addition the hedgerow weeds supported a population of injurious insects. Con- siderable clearance had to be effected. A second difficulty threatened to be much more serious. Wireworms began to appear and to attack the crops. Provision was therefore at Io once made for studying them with a view of finding the best way to cope with the evil. Mr. A. W. Rymer Roberts undertook this work. The attack was not so serious as was feared; it was, however, sufficient to show the urgent need for the work. Two lines of investigation were followed. The natural way of life of the wireworm in the soil was studied in order to obtain full information as to its habits and its weaknesses ; and search was made for some insecticide or method of treatment that would prove fatal to the wireworm. ‘The last problem speedily became linked up with another that has been under investigation for some time and had proved rather baffling—the search for a practicable sterilising agent. As shown in previous reports, if soil is treated with a volatile antiseptic there is a considerable gain in available nitrogen compounds and therefore an increase in productiveness. Toluene and carbon disulphide were very effective in pot experiments but not in the field ; some of the tar acids, notably cresylic acid (the chief constituent of the so-called ‘liquid carbolic acid ” ), proved to be more suitable on the large scale. Tavestigation has shown that carbon disulphide, in quantities practic- able on the farm, is of no great insecticidal value. In the pot experi- ments this did not matter, as insects and celworms were rigidly excluded, being outside the scope of the invesiigation ; im the field, however, they were important factors. The broad result of the efforts to put soil sterilisation methods into praciice is that the process is effective but not economical in comparison wiih cheap sulphate of ammonia or nitrate of soda. The situation would be completely altered, however, if a partial sterilisation agent could be found that is at the same time a soil insecticide ; we should then obviously have 2 much better prospect of success in field work than we have had in the past, when we confined ourselves to the gain in available nitrogen only. Mr. Tattersfield is, therefore, preparing a series of sui itable substinces in the Chemical laboratory ; Mr. Roberts is testing their larvicidal effect on wireworms and other pests; and through the gencrosity of Mr. W. B. Randall it has become possible for another worker, Mrs. D. J. Matthews, to study their effects on the b»cverial and protozoan population. Two groups of substances are being tested: (q) compounds of known constitution, so as to see what chemical groupings are most effective, knowing w hich it may be possible to formulate specifications for sub- mission to a Works chemist, and (0) certain typical waste products now available in quantity at a cheap rate. The resistance of the wireworm to certain poisons such as carbon disulphide, toluene and formaldehyde, which ought to be effective but are not, is of considerable interest. Dr. Malcolm Laurie is studying the morphology of the wireworm in the hope of gaining information that will be of service. The most potent soil steriliser and larvicide is heat ; further attempts have therefore been made to devise means of heating soil cheaply on a large scale. In the form first worked out at Rothamsted the method cost 5/- per ton of soil, or about £300 per acre of land, a hopelessly impractical proposition for the farmer. But the nurserymen in the Lea Valley succeeded in bringing down the cost to below {£40 an acre at pre-War prices. This figure is not eatirely out of the question for special types of crop production, such as market gardening and nursery W ‘ork ; ; 1f the cost could be further reduced to one third or one quarter, the method would be quite practicable for potato growing, ete. II Captain Guinness and Mr. Richards have designed a machine by means of which a reduction in cost will be effected, though whether to a sufficient extent is not yet clear. A further set of problems arises out of the weed flora. Although the field chosen for the ploughing up experiment had been down to grass for ten years there was a considerable development of arable weeds as soon as it was ploughed. ‘This result had been anticipated, and before the land was broken up samples of earth were taken inch by inch in succession down to twelve inches at various points in the field. These were transferred at once to sterilised pans and kept moist in the glasshouse, careful watch being kept by Dr. Brenchley to see what would happen. A number of arable weeds came up from every sample, especially Polygonum aviculare and Atriplex patula. Now the conditions of the experiment were such that these young plants could only have arisen from seeds that had lain buried in the soil, dormant so long as the land was in grass, but springing into activity as soon as tillage conditions were restored. The test was repeated in similar manner on other grass fields of known age and history. Suil from grass fields 30 years old afforded a copious flora of arable weeds, especially at the depth of six to twelve inches; that from fields 60 years old gave fewer arable weeds, and trom fields 200 years uld none at all. These observations prove beyond doubt that the seeds of certain arable weeds can survive in the soil over a considerable period when deeply buried by the plough. Another series of problems relates to the utilisation of the stored up fertility of grassland. During the years when it was down in grass, the soil gained fertility through the various agencics wlready studied in these laboratories. Now that it is ploughe d up the fertility is being liberated. Unfortunately the process is very vigorous, the decomposi- tion of the organic matter proceeding so rapidly that the crop cannot utilise the whole of the nitrogen compounds; terzis, therefore, a good deal of waste. In virgin countries the weasteze of the original soil fertility often amounts to 50 or 60 per cenv; 10 this country a higher level of production is attained aad therefore a greater degree of utilisation may be expected ; but there is still likely to be loss. This problem is not a new one ; it has been under investigation here by Mr. Appleyard and Mr. Horton from the soil side, whilst Mr. Richards took up the pzrallel case of the manure heap. Unfortunately the soil investigation was not able to keep pace with the manure heap work, and so the problem has become urgent before we have found the solution. Sufficient has emerged, however, from Mr. Appleyard’s and Mr. Richards’ work to reveal the main factors in the problem. So long as the land lies in grass the conditions are not specially favourable to aerobic organisms. The soil atmosphere contains in both samples about one per cent. of carbon dioxide calculated on the entire volume, and locally a good deal more ; there is also a reduced percentage of oxygen. Directly the grassland is ploughed up the conditions become more favourable. The nitrogen compounds are broken down in the first instance to ammonia. This action has been attributed in the past to bacteria, but we have obtained evidence that the process is more than a simple bacteriolysis. The amount of ammonia produced does not show the direct and immediate relationship with the number of bacteria that one would expect. An increase in bacterial numbers is not at once followed by an increased production of ammonia ; there is a delay of two or three weeks to which our present knowledge affords little clue. The loss of nitrogen is partly due to a definite evolution of gaseous nitrogen. This does not occur in entire absence of air or in complete access of air, but only under intermediate conditions of aeration. This result is of interest as showing that the evolution of nitrogen is due neither to a simple oxidation nor to a simple reduction but to some more complex action. The application of the discovery to manure heaps has already been mentioned and is further discussed on p. 28; its application to the particular soil problem under consider- ation is, however, less easy. Ill. THE STUDY OF THE ORGANISMS OF Danson. Mr. Appleyard has shown that the numbers of bacteria are pro- foundly affected by the soil temperature in late autumn, winter, spring and early summer, but during summer and early autumn soil moisture is more important, and rainfall still more so. The effect of rainfall has been studied by Mr. Richards, who finds that rain always brings down oxygen in solution, so that dissolved oxygen is maintained in direct contact with the plant roots and the soil organisms. Experiments are now in hand to study the effect of this renewal. But these seasonal factors do not account for the whole of the variations in bacterial numbers ; some other factor is clearly at work. Miss Crump has therefore developed the dilution method of counting soil protozoa and has improved it considerably ; she has made system- atic counts of bacteria and protozoa in two of the field soils at intervals of about ten days during over two years, and has plotted the results in a series of interesting curves. The results show beyond doubt the existence of a living protozoan fauna in the soil, multiplying and dying, and fluctuating considerably in numbers ; the amoebae vary in numbers according to the soil conditions from a few hundreds up to 50,000 per gram; the flagellates vary up to 100,000 per gram, while there are also numbers of thecamoebae which are now under investigation. The bacteria do not exceed, and rarely even approach 50,000,000 per gram ; their number is usually 10,000,000 to 20,000,000 ; and as the protozoa are much larger than the bacteria, it is evident that the total mass of protozoa is comparable with that of the bacteria. Further, during the summer and autumn it is found that the number of bacceria present is closely connected with those of the protozoa ; when one is high the other is low, and vice versa. This, of course, is what was expected on the view already put forward, that the protozoa are detrimental to the soil bacteria. A new possibility is also opened up, however ; the bacteria may be detrimental to the protozoa. The protozoan fauna is very interesting and its mode of life urgently needs working out. Miss Crump has made considerable progress with these difficult problems ; the results promise well. The possibility of the production of toxins in the soil by bacterial action has been studied by Drs. Hutchinson and Thaysen, but no evidence whatsoever could be found justifying the belief that they are present. : eo IV. PLANT NUTRITION PROBLEMS. A considerable portion of Dr. B-enchley’s time has been taken up in studying the effects on plant growth of various substances to test possible fertilising values, this information being wanted for the Food Production Department. Her ordinary work has, however, been maintained ; the investigations on weeds have been extended; a com- plete botanical analysis of the herbage of the grass plots has been made and will be examined in detail; also an ecological study has been made of the recolonisation of arable land allowed to revert to natural conditions—the cases examined being Broadbalk and Geescroft Wilder- nesses, which went out of cultivation in 1881 and 1882 respectively. A problem of importance in water culture work has been further studied. It has been shown that the amount of plant growth is related to the concentration of the nutrient solution and increases with it to a maximum set by the other conditions. The effect of certain organic toxins, especially cyanides and phenols, on plant growth has also been studied. This investigation was necessi- tated by the circumstance that some of these substances are of consider- able interest as possible insecticides and partial sterilisers, and it is important to know how they are likely to act on the young plant. The information given by water cul.ares is not complete and needs checking by direct studies in soil, but so far as it goes it has the great advantage of simplicity and freedom from complication. The investigations on the sugars and starch in plants begun by Mr. Davis in rgir in conjunction with Messrs. Daish and Sawyer were continued by him until 1915 when he took an appointment under the Indian Government ; they were then handed over to Mr. Horton. Considerable attention was devoted by Mr. Davis to the leaf of the mangold, and samples were taken at regular intervals for analysis. Starch and maltose are entirely absent from the leaf after its earliest growth. In the early stages saccharose occurs in excess of the hexoses in the leaf, but later in the season, when sugar is being stored in the root, the hexoses exceed the saccharose in amount. In passing from leaf to root the proportion of hexoses greatly increases ; in the midribs and stalks the hexoses always predominate and their predominance becomes more and more pronounced as the season advances. The results indicate that saccharose is the first sugar formed (as Brown and Morris have already shown), and that it is not carried to the root as such, but changed into hexoses for the purposes of transit, and then changed back again to saccharose in the root. The mechanism of the change in the root was not discovered. Apparently, similar conclusions apply to other plants, the vine, potato, dahlia, etc. The absence of maltose was very carefully confirmed ; over 500 analyses of various leaves and germinating seeds were made, but in no case was any trace of maltose found, even where starch was being broken down and where therefore maltose must have been formed. This is attributed by Messrs. Davis and Daish to the widespread distribution of the enzyme maltase which breaks down the maltose at once to glucose. The degradation of starch, in their view, involves at least three stages :* the transformation of starch to soluble starch and dextrines, brought about by special liquefying enzymes ; the conversion of dextrines to maltose by the enzyme dextrinase ; and the conversion of maltose to glucose by maltase. 14 OTHER PROBLEMS NOW IN HAND. The farmer’s task in the future will unquestionably be to increase his output, and the problems connected therewith will necessarily determine the programme for future Research work. An examination of the yields of wheat obtained by farmers during the past 4o years brings out some interesting and significant points in regard to the application of science to agriculture. When the yields are simply stated in five year averages, there is seen to be a small tendency to rise since 1895, when attempts to disseminate scientific advice among farmers became common. When, however, the yields are examined in more detail a more interesting relationship is brought out. In good years the average yields rise to 33 or 34 bushels—iittle better than was obtained in the ’sixties ; but in the poor years the crops no longer sink so low as formerly. Averages of 26 or 27 bushels not uncommon in the ’eighties and early ‘nineties are not now obtained and in our worst years we only fall to 29 bushels. Itis, of course, arguable that seasons are better than they used to be, but it is also possible that in bad years farmers are more ready than they were to apply scientific principles ; when a crop is obviously suffering the help of an expert is sought. It is a matter, however, for serious consideration that in spite of a great amount of experimental work the yields in the good years are no better than they used to be ; we seem to have got into an impasse, an average of 34 bushels being our best result. Several factors seem to be at work. In good years, when the crop is looking well, the farmer tends to let well alone. He justifies this course mainly on the ground that if he “‘ does” his crop too well it will go down. So widespread is this conviction that probably little progress will be made in wheat-growing until the straw can be strengthened. Again, on many soils and in many seasons wheat will not properly “ corn out” ; attempts to increase the crop lead to a great increase of flag but not of grain. A more complete knowledge of tillering is also necessary. Further, the depre- dations of insect and fungoid pests tend to increase with closer cropping, which is an essential part of any method for increasing output. We are faced, then, with at least four problems : we must strengthen the straw, improve the tillering, regulate to some extent the development of grain, and control the pests. Until these are all solved we cannot hope to get much further with increased wheat yields. There are two ways in which these problems may be attacked ; the breeder may find or produce varieties possessing the necessary properties, and the physiologist may succeed in elucidating and controlling the factors concerned. The former method 1s already being applied at Cambridge and at Merton; it is hoped to apply the second method at Rothamsted. When conditions become more normal, we hope to secure the services of a statistician who can apply modern statistical methods to the great mass of data accumulating at Rothamsted, and of a trained physiologist who can make detailed observations in the field and reduce the problems to terms in which they can be investigated in the laboratory. —s ss - T5 THE LIBRARY. With the growth of the Experimental Station in recent years it has become imperative that a good agricultural library should be assembled. Considerable efforts have therefore been made during the last four years to collect the more important agricultural literature, and now that the new buildings are complete it has been found possible to provide a suitable Reading Room and adequate storage space for the Library. The furniture for the Library was kindly given by Sir John Brunner. Sir John Lawes had given a small collection of books and journals to the Laboratory, and for many years these were all that the Institution possessed. Expansion was begun in 1913, when the late Lady Gilbert generously presented the library of Sir Henry Gilbert, the binding of which was completed by Mr. H. T. Hodgson. A grant of £300 was then made by the Carnegie Trustees to complete broken sets of Journals. Gifts of choice and rare books on husbandry have been made by Lady Wernher, Capt. the Hon. Rupert Guinness, Messrs. T. H. Riches, V. T. Hodgson, Robert Mond, J. Martin White, and others, and gifts of books and journals by the Royal, the Chemical, the Linnean, the Statistical, Meteorological, Royal Horticultural, Royal Agricultural and other Societies, and by the more important Agricultural Depart- ments and Experimental Stations throughout the world. Mr. Otto Beit kindly gave £150 for the purpose of binding. A special Library Fund is also raised by the Society for Extending the Rothamsted Experiments for purchases, and the generosity of many donors, notably Mrs. and Miss Miller, Sir Norman Lockyer, Dr. H. T. Brown, Mr. Marlborough Pryor, and Mr. J. H. Howard, has provided much needed books and money. Altogether some 10,000 volumes dealing with agriculture and the cognate sciences have now been collected and card indexed by the Librarian, Miss Adam, and her assistant, Miss Cumberland. The indexing is done on auniform plan which differs from the Dewey decimal method, as expanded by the International Bibliographical Institute at Brussels, only in details where deviation is absolutely necessary, but it is so arranged that any student familiar with this system can at once find his way through the Catalogue. Moreover, the indexing is not confined to the titles of the volumes, but is extended to cover the more important agricultural experiments, with the result that the looking up of information is greatly facilitated. The Library is much used by agricultural experts and students of our own and other countries and by various Government Departments. FARM REPORT. OCTOBER, 1914 TO SEPTEMBER, 1915. So little rain had fallen in September of rorq that the land was left too dry to plough, and some difficulty was experienced in getting a seed-bed for the oats. On Oct. 13th and r4th, however, there was sufficient rain to soften the ground and allow of the drilling of the oats, but unfortunately the rain did not stop then, and by the end of the month so much had fallen as to interfere considerably with potato digging. The total rainfall for the month was not excessive, indeed it was below the average, being only 2.3 inches as compared with 3.2, but the distribution was not satisfactory for farm work. November opened with fine weather and wheat was sown during the 16 first fortnight, but from the 15th onward a succession of morning frosts kept the men off the fields, often until dinner time. The winter oats were looking exceptionally well, but it was not possible to complete the wheat-sowing this month. December was extraordinarily wet, no less than 7.5 inches of rain falling as compared with the average of 2.5 inches. But so dry was the ground at the beginning that ploughing met with less interruption than might have been feared, and the corn continued to thrive, looking better than was anticipated. ‘The first three weeks of January were more or less rainy, but the last was fine ; the total rainfall was again above the average (3.7 as compared with 2.3 inches). There were light frosts at intervals, but the mean temperature was not unusual. Through- out the season ploughing had not been hindered for more than a day or so at a time, and the corn still looked quite well, although some was not strong. February was a very broken month. It was unusually wet, rain, hail and snow amounting to 4.2 inches as compared with an average of 1.8, and there was frost almost every night. In con- sequence the work on the barley land was much delayed. The winter had been the wettest and muddiest on record, and spring opened badly. March was, generally speaking, unfavourable for farm work. The land was too wet for barley sowing until the 22nd, a full week later than we like. A week of frost at the end, however, improved the conditions of the soil, though it delayed the commencement of drilling till 10 or rz a.m each day. The winter corn only made slow progress. April was better ; work proceeded with little interruption, and the weather was dry but cold. The winter corn still made little headway, though keeping healthy ; the barley, however, was suffering from the dry cold. Potato setting was completed on the 21st, and mangolds drilled on the 22nd. May began with fine weather and drying winds, but there was bitterly cold rain in the middle of the month, 1.4 inches falling on the 13th. The last fortnight was dry, though the wind was north and the nights were cold; for the whole month the hours of sunshine were 236.9, against an average of 199.6, but the mean tempera- ture was no higher than the average. The winter corn and the barley looked fairly well, but the grass after a good start was checked by the dry, cold winds, as also were the roots. ‘The drought continued almost throughout June ; the total rainfall for the whole month excluding the last day was only 4 inch; on the 30th, however, heavy rain came, and over 1.2 inches fell. There was an unusual amount of sunshine, 242 hours as compared with an average of 198, but the wind being often north and east the nights were cold, and the mean temperature was no higher than usual. All crops except wheat suffered from the drought badly ; barley turned yellow at the bottom, winter oats made very little straw, grass was short, and the mangolds grew very slowly and irregularly, especially on the plots where no farmyard manure had been applied; indeed, one of the most striking demonstrations of the season was the enormous difference between the mangolds grown on land receiving farmyard manure, and those that had had artificials only. The weather in July was broken; commonly, the mornings were fair and the afternoons dull or wet. The corn became beaten down and although much of it picked up again the grain did not become plump, in the persistent absence of sunshine. The total rainfall was 4.4 inches, and the hours of sunshine 188.7 ; the average values being 2.5 and 217.9 respectively. Potatoes developed a good 7 deal of haulm, and the aftermath of the grass came on well. Horse and hand hoeing were carried on frequently but under difficulties, the weeds commonly rooted again by the rain. Sprouts and Savoys were planted out by the 15th on their own ground and in the gaps in the swede crop. August began with two days of heavy rain, 1.7 inches falling, and showery weather followed during the first fortnight, so that the cut corn did not dry and could not be carted. Fortunately the weather was cool, so that no great amount of sprouting occurred in the shock. Fine, warm weather came later and enabled the corn to be gotin. Much of the corn being lodged, the harvest was slow and expen- sive, and a good deal of hand cutting was necessary on the bad spots. The fine weather continued throughout September, so that the end of the harvest was attended with little difficulty. Sufficient rain fell to soften the land for ploughing, and a beginning was made with the work for next season. Much of the wheat suffered from smut, the seed by an oversight not having been pickled. The yield of barley was poor, being only 34 quarters. Potatoes, however, did well. During the season 1913-1914 the top or western half of Broadbalk had been left fallow in order to check the widespread growth of weeds, the chief of which was Alopecurus agrestis (Slender Foxtail). It received its autumn manures but no spring dressings. In the following season 1914-1915 it received no dung or autumn manures, but had “the spring dressings as usual in 1915 The lower or eastern half of the field had been cropped in 1913- 1914, but it was left fallow in 1914-1915: during this period it received no autumn or spring manures. As June was very dry the fallowing did not prove entirely effective in killing the weeds. OCTOBER, 1915, TO SEPTEMBER, 10916. In this season the corn crops gave considerable promise, but in the end their yields were disappointing, there being more straw than grain. The potato crop did badly. The season opened well. October was a fine month; the rocts continued to grow and grass yielded a bountiful aftermath. The catile flourished, and towards the end of the month were brought into the yards off the grass. Ploughing was pushed on, the oats were sown and everything was ready for wheat when unfortunately on the 23rd the fine weather came to an end and the rain started. Broadbalk Field was drilled on November 4th and 5th with Squareheads Master, which went in very well, but a heavy storm on the rith and 12th brought 14 inches of rain, and this being followed by snow put an end to wheat drilling, so that part of Little “Hoos Field had to be left. In spite of these storms October and November had on the whole been drier than usual, but November had been distinctly colder :— RAIN. MEAN TEMPERATURE. Oct. Nov. Dec. Oct. Nov. Dec. ns ns. ws I9r5° Tg 2 December, however, brought a great change, and again as in 1914 it was very wet, there being 5.1 inches of rain. Rain fell on 25 days out of the 31 as compared with 17, the average ; the weather, however, was mild, the mean temperature being 41°.1 as compared with 38°.3, the average of 35 years. Ploughing was considerably delayed, and a good deal of grass began to grow in the wheat on Broadbalk. January was also mild, the mean temperature being 43°.8 against the average 36°.9 ; rain fell frequently, though the aggregate amount was somewhat below the average. The drilling of wheat was resumed in Little Hoos Field on the 17th, and thus we were able to make a comparison of the effects of late and early sowing. The really cold weather began in February and was accompanied by much rain, and from the 22nd onward by snow which, falling on the already sodden ground, did much harm to the crops. March was very similar in character ; the snow persisted until the r2th, having been about for three weeks. A wholly excep- tional snow blizzard occurred in the afternoonand evening of March 28th, bringing down hundreds of trees in the neighbourhood and almost clearing several acres of the wood adjoining Sawpit Field; the trees blocked the roads, and for a long time hindered travelling. The snow and rain caused considerable injury to the crops and gravely prejudiced the prospects for spring sowing. April, however, was much better, being drier and warmer than the average ; May began well, and after a spell of rain in the middle some really hot weather set in, making a splendid start for the new summer time, which began on the night of May zoth-21st, when the clock was put forward an hour so as to give more hours of daylight. The farm hands, however, preferred the old time, as also did the Meteorological observers ; the records were therefore taken as usual at 9 a.m. on sun iime, though it was 10 a.m. by legal time. So the farm hours remained from 6 a.m. to 5 p.m. by sun time, but from 7 a.m. to 6 p.m. by legal time. This arrangement was in force till the might of September 30th-October rst, when the clock was put back an hour and sun time once more became legal time. Unfortunately the fine weather of the end of May was not kept up ; June opened with a cold, dull day, and remained colder and duller than any previous June since our records began in 1878 ; the mean tempera- ture was only 51°.8, and the hours of sunshine 136.7 against average values of 57°.3 and 197.8 respectively. Much of the local apple blossom was ruined. July was warmer, however, and there was rain on the r2th and 13th, followed by fine hot weather. August began with rain, but was mainly dry, warm and cloudy, the hours of sunshine being 174.4 against an average of 198°6; it was a good month for harvesting, which began on the 7th and went through without intermission. September was fine, and the harvest being over early, we were able to start ploughing at the beginning of the month, and get a great deal of it done before the end. Thus the season closed with the work well in hand for next year. The crop position looked very satisfactory, better indeed than it actually was. In view of the need for increased food production we have given a spring dressing of 1 cwt. of sulphate of ammonia and 2 cwts. of superphosphate to practically the whole of the corn crops. Admir- able growth followed ; the crops were very heavy, and when the harvest was brought home there was such an array in our stacks as had not been seen for many years, overflowing from the Dutch barn and yards 1g into the adjacent fields. Oats and barley especially had grown long straw. When, however, the threshing was done the yields obtained were disappointing ; the grain was very low in proportion to the straw, and in spite of the abundant promise of July the yield was only 34 bushels of wheat, 34 of barley, and 32 of oats. These disappointing results were not uncommon, and they were widely attributed to the cool, sunless June. It would be interesting to examine this question more fully. The early sown wheat in Little Hoos Field proved superior to the later sown, thus again demonstrating the value of early sowing on heavy land like ours. The first cut of clover on Long Hoos Field was very big, and the second growth started well. The grass also did well. Swedes and mangolds were good, but potatoes did badly, the yield being only about 4 tons per acre. OCTOBER, 1916, TO SEPTEMBER, 1017. This was distinctly a bad season for hay and winter corn, though unusually good for potatoes and mangolds. October was wetter and duller than usual; the bright sunny weather was lacking, and instead of an average of 104 hours of sunshine we had 88.5 hours only ; in place of eighteen wet days we had 24 ; the rainfall also was above the average. November was still wetter, the total rainfall being 4.1 inches against 2.6, and to make matters worse a heavy storm of snow and sleet came on the 18th, which was followed by rain, so that drilling and germination were greatly hampered. The winter oats had been sown by the middle of October, and they came through satisfactorily ; but the Rivetts wheat could not be sown till the first week in November ; it went in badly and made no progress at all. At the end of the month the Red Standard was sown. December began with frost and clear weather, but ended with rain, snow, and fog ; it was wetter and much colder than usual, the mean temperature being 34°.7 F. in place of 38°.3F. During October, November and December there was no less than 10.6 inches of rain, this being 2.2 inches above the average for these months. When the new year began the oats were still looking tolerably well, but the wheat was only just beginning to appear, and some of the clover (Harpenden Field) was suffering so badly and had responded so little to its mending with Trifolium that it was ploughed up and replaced by wheat. January was drier than usual, but much colder; after the first week there was frost every night without exception and this continued throughout February ; this was the longest spell of cold weather since 1895. Unfortunately for the wheat, oats and clover there was no protecting layer of snow, and the Rivetts wheat in particular suffered badly and looked pitiable ; towards the end of February the frost broke leaving the ground very cold and wet. Early in March the ground began to dry somewhat, and the men put in overtime to try and make up the arrears of ploughing ; the last of the wheat—Red Marvel—was sown in Harpenden Field on March 16th. The Rivetts wheat looked now as if it might yet recover ; the best was therefore left alone, some was mended with barley and the rest was ploughed up. Unfortu- nately the improvement in the weather was very short-lived, and the promise of better things was not fulfilled ; March remained cold with bitter N.E. winds and frequent snowstorms, and April was no better ; the first half of the month was very cold, with snow the greater part of the time ; towards the end, however, the wind got to the N.W. and the days were warmer, though the nights were still cold. It was rightly called an ‘“‘ Arctic Spring,” and its effect was intensified by following so wet a winter ; the mean temperature of each month was much below the average :— Dec. Jan. Feb. March.|} Apnil. IgI6-1917 ; ele BAe 27 gh | =a2ca¢ Average for 35 years | 38°. "9". Gram 41°.0 | 45°.6 | | WwW I Ww W looms) The low average was not the result of a few specially severe spells but of persistent cold weather. Until the last ten days of April there had only been four occasions since the beginning of the year when the maximum air temperature rose above 50°F. The last ten days of April were warmer, and we were able to complete the barley sowing. May opened with glorious sunshine; rarely can the advent of warm weather have been more welcome. But even this was not wholly satisfactory ; the nights remained cold, and there was only one shower of rain, which might have done great good had it been warmer, but unfortunately it was cold and in consequence the grass was not able to start growing. On the other hand the dry weather enabled us to prepare an excellent tilth for the mangolds and to get the potatoes in well, so that these two crops started under very favour- able conditions. The drought continued throughout June, being broken only at the end, when there was a heavy storm ; the grass made very poor growth and the hay crop was poor. There was some distinctly hot weather, but on the whole the temperature and sunshine were not above the average. July was not a good month ; there was a great deal of rain and on the 29th and 3oth a very heavy storm. This was very unfortunate, for it came just as we were about to begin harvesting, and it was followed by five days of heavy rain in early August, which beat the oat crop down flat and made our task very difficult. Misfortune dogged our footsteps throughout the whole of the harvest ; on two occasions when corn was ready for carting heavy rain fell and the sheaves had to be left and turned. The rainfall for the month was even greater than in July and far in excess of the average. The figures were :— IQI7. Average for 60 years. july Ae 4.2 2.5 August . 6.0 2.7 This greatly protracted the harvest and made it very costly. Barley carting was only finished on September 22nd and the wheat was not all in till October. The work had to be done by old men and children. The straw was brittle and much of the barley had kinked badly at the neck ; the result was that many heads broke off and a great deal of the corn never came in at all. A certain amount of eleaning was attempted, but owing to shortage of labour it had to be abandoned. As a set off against the bad corn and hay harvests the potatoes and roots did splendidly. And although the hay crop had been short the _—=——_ - aftermath was good—so good indeed that the country took on an unusually green colour all through the late summer. The effect of this abnormal season on the growth of the crops was very interesting. The following-did well :— The winter oats that had started well before the bad weather set in ; The winter wheat that had received sulphate of ammonia in autumn, and had therefore started growth early ; The winter wheat that had been ploughed in and not drilled in the ordinary way. This, however, did not finish much better than the drilled wheat. The late sown wheat—Red Marvel sown in March. The clover in Little Hoos Field, especially on the dunged plots. The potatoes and mangolds went in well and did extraordinarily well. On the other hand :— The winter wheat, especially Rivetts, did exceedingly badly; it went in badly and never gave a plant. The Red Standard was better. Barley was patchy, and Hay gave a poor crop. The conditions were very favourable to thistles, which gave a good deal of trouble, especially on grassland. ‘ Langley Beef” (Sonchus arvensis) was also troublesome in the newly broken grass in New Zealand. The legal “summer time” came into force on the morning of April 8th and lasted till the evening of September 17th, during ‘this period the clock was put one hour in advance of the true time. As in 1916, however, the meteorological observers and the farm workers kept to the sun time and not the legal time. THE SEEDS COURSE.—As the clover leys during the past few years have tended to be patchy, it has been decided to give up pure clover and to grow the following mixture instead :— Italian Rye Grass. : , : 9 lbs. Cocksfoot : : ; : : 2 lbs. Timothy : h ; : : 4 lbs. Broad Red Clover . . : ; 3 Ibs. Alsyke Clover : ; : é 2 lbs. 20 Ibs. Alsyke Clover shows less tendency to fail than the Red Clover, but if both fail, there will still be a growth of grass that can be made to yield well by treatment with nitrogenous fertilisers. THE GREEN MANURING EXPERIMENT.—Owing to the shortage of labour this experiment has been discontinued during the War ; it is hoped, however, that we may be able to resume it afterwards. THE EXPERIMENT ON THE RESIDUAL MANURIAL VALUES IN LITTLE HOOS FIELD.—After this had gone on for atene years, an account of it was written by Sir A. D. Hall (Journ. Roy. Ag. Soc., 1913, 665-672). During the whole of this first series aan has been no clover or seeds mixture grown; a second series has now been started differing from the first in that clover or a clover mixture is to be grown every fourth or fifth year. The first clover crop was taken in 1916-17 and was very good (p. 63). to tN PAPERS PUBLISHED; SOIL PROBLEMS. I. ‘“‘ The Atmosphere of the Soil: its Composition and the Causes of Variation.” E. J. Russetu and A. APPLEYARD. Journal of Agricultural Science, 1915. 7, 1-48. The free air in the pores of the soil to a depth of six inches is very similar in composition to the atmospheric air, but it differs in two respects : (a) It contains more carbon dioxide and correspondingly less oxygen, the average in 100 volumes being 0.25 volumes of carbon dioxide and 20.6 of oxygen against 0.03 volumes of carbon dioxide and 20.96 of oxygen in atmospheric air. (6) It shows greater fluctuation in composition. Usually the sum of the carbon dioxide and oxygen is only slightly less than in atmospheric air, but at periods when nitrates rapidly increase there is a perceptible falling off of oxygen, and a still greater one in waterlogged soils. Besides this free air there is another atmosphere dissolved in the water and colloids of the soil. This consists mainly of carbon dioxide and nitrogen and contains practically no oxygen. The fluctuations in composition of the free soil air are mainly due to fluctuations in the rate of biochemical change in the soil, the curves being similar to those showing the amount of nitrate and the bacterial counts as far as they were taken. The rate of biochemical activity attains a maximum value in late spring and again in autumn, and minimum values in summer and winter. In autumn the bacteria increase first, then the carbon dioxide rises, and finally the nitrate increases. From November to May the curves closely follow those for the soil temperature which thus appears to be the dominating factor ; from May to November they follow the rainfall and to a less extent the soil moisture curves. The difference between rainfall and soil moisture indicates that rainfall does something more than add water to the soil. It is shown that the dissolved oxygen brought in is probably a factor of considerable importance in renewing the dissolved soil atmos- phere and facilitating biochemical change. Grass land usually contains more carbon dioxide and less oxygen than arable land, but we cannot attribute the difference wholly to the crop owing to the large differences in soil composition and conditions. It is difficult to ascertain the precise effect of a crop, but as the soil differences are eliminated so the differences in composition of the soil air becomes less and less. No evidence could be obtained that the growing crop markedly increases the amount of carbon dioxide in the soil air; if it gives rise to any great evolution of carbon dioxide in the soil it apparently exercises a correspondingly depressing effect on the activities of soil bacteria. This result agrees with one obtained earlier in reference to the nitrates in the soil. Such weather conditions as barometric pressure, wind-velocity, variations in temperature from the mean, small rainfall, ete., seem to have but little effect on the soil atmosphere. to ww YI. “ The Influence of Soil Concitions on the Decomposition of Organic Matter in the Soil.” E. J. RussELL and A. APPLEYARD. Journal of Agricultural Science, 1917. 8, 385-417. The changes in bacterial numbers and in nitrate content of the soil and in carbon dioxide content of the soil air were determined at frequent and regular intervals during several seasons on five different plots of land, and the results are set out on curves. There is sufficient resemblance between the curves for bacterial numbers, carbon dioxide (except for a period on cropped land), and nitrate content to justify the conclusion that they are all related. The curve for nitrates, however, is always behind that for bacterial numbers, the lag amounting to two or three weeks. Assuming that the curves are connected, this would indicate two stages in nitrate production: one related to the bacterial numbers, the other not. Evidence is brought against the view that the stages are simply ammonia production and then nitrate production ; the division has apparently to be carried further back-and ammonia production to be divided into two stages. The biochemical decompositions in the soil are determined in the first instance by the temperature and do not proceed to any notable extent below 5° C. As soon as the temperature rises in spring, action takes place rapidly. But it soon slows down and other factors begin to operate. Moisture is one of them. Action came to a minimum in June, when the moisture fell to ro per cent. by weight of the unmanured soil and 15 per cent. by weight of the dunged soil, or 16 and 22 parts respectively by volume, assuming there was no contraction. Rainfall is an even more important factor, a shower of rain having a notable effect in starting the decompositions. It seems probable that the dissolved oxygen plays an important part here. The growing crop exerts a depressing effect, though whether by taking up the dissolved oxygen, giving out carbon dioxide, or some other action is not clear. The fluctuations in bacterial numbers are not wholly explicable as functions of the temperature and moisture content. Some of the rises and falls are of the kind obtained during the investigations on partial sterilisation ; further work on this problem is in hand in our labora- tories. III. “ Dissolved Oxygen in Rain Water. Eric HANNAFORD RicHaRbs. Journal of Agricultural Science, 1917. 8, 331-337: Rain water was collected in a special form of apparatus, and the amount of dissolved oxygen was determined by Winkler’s method on each occasion when o.3 inches or more fell—this being the lowest rain- fall that gave sufficient liquid for the analysis. During autumn, winter and spring, when the temperature was below 15° C., the rain was practically saturated with oxygen, the quantities found being on an average 93 per cent. of Dittmar’s complete saturation values for distilled water. Rain collected in summer, however, was less saturated, the amount of oxygen being 85 per cent. of the full saturation value. The difference was carefully examined and found to be real; it is not an accident of the method of collection. It is difficult to under- stand why the summer rain should contain less oxygen than rain falling in the rest of the year, especially in view of the circumstance that the relative temperatures of the rain clouds and of the air at ground level ought to cause super-saturation in summer and not under- saturation. The significance of the dissolved oxygen in the soil is discussed. IV. ‘‘ Methods for the Examination of Soil Protozoa. CHARLES HENRY Martin and KenneTH R. Lewin. Journal of Agricultural Science, 1915. 7, 106-119. Descriptions are given of some of the organisms isolated in the trophic state by the two methods already described (Annual Report for 1914, page 19). Amoebe and thecamcebe were most frequently met with ; ciliates and flagellates* were relatively rare. The organisms described are Euglypha and Chlamydophrys among the thecamcebe ; Chilodon, a ciliate; Vahlkampfia so, a limax amceba, Ameba gobaniensis and Ameba cucumis, lamellipodian ameebe, and Boda caudatus, a flagellate ; all these had been found in the trophic state in the soils examined. V. ‘‘ Soil Protozoa and Soil Bacteria.” E. J. Russett. Proceed- ings of the Royal Society, 1915. 89, 76-82. The experimental evidence of the existence in soil of a living protozoan fauna in the trophic, as distinct from the encysted, state is collected. The fauna is shown mainly to consist of flagellates, amcebe and thecamcebe ; ciliates only being present in smaller numbers, and probably for the most part in the encysted form. This conclusion is in harmony with Goodey’s work, and with all the facts at present ascertained. VI. ‘‘ The Utilisation of Organic Residues for Nitrogen Fixation and the Losses of Nitrogen from the Soil.” HENRY BroucHam Hvutcurnson. Journal of Agricultural Science, 1918. 9, 92-111. It has long been known that appreciable quantities of gaseous nitrogen may ‘be assimilated from the atmosphere when a soil or a culture of a soil organism (Azotobacter chroococcum), is supplied with soluble carbohy drates under laboratory conditions. The present paper shows that this action also occurs under natural conditions, and that plant residues can be utilised for nitrogen fixation in the labora- tory and in pot experiments. Crop increases may also be obtained when field soils are treated with an easily oxidisible carbohydrate such as sugar, and these may be attributed to the assimilation of atmospheric nitrogen. The effect of carbohy drates and of plant residues on the soil is shown to be complex, and under certain conditions—when the soil temperature is low, or when the applications are made too near to the time of sowing—marked depression of the crop may occur. This effect appears to be largely due to destructive processes, which result in a withdrawal of available nitrogen compounds or a loss of free nitrogen from the sous *Subsequent work has Son n that amoebe and thecamcbhe are much more numerous than citiates, though, as a matter of fact, the flagellates are often more numerous still—not less so as these earlier observations ‘suggeste d. iS) On VII. “ adac ‘peystuy ; “ueseq | ‘uvseq Sunavg | Bunszeg | Sunyn-) oad Sen ieee eer olay ST, 'bZ ‘AON | Cla ‘AON | zee rT “ady | TT Ae CN os BONS | CL, ‘bz Ady | ST, ‘be “ady | SIG, WIE 2X0) I Te ABN | og Avy wee CI ‘idy | hI Ady | : Gad, 259) ady | Deo (ery avo | he I ARKO). || © [, OL AON ex T, 02 “AON | [. ‘ST “390 | 1, 6 AON | Je QURAT CT, os soun'{ | .€7 aunt | po APIA “-- +f oun | gc ‘adv | ° ‘uedaq BUIMOGS | ‘JO[q parnsvayy | Oo, aunt | : | =) J | “ynoO FUIS Sulzer) aye eee ulnuog wnusey aqO[t) MOT[PA $,uO PNG es “* ssolg oseun{] Jasejy sproyarenbs ie SUIMIIE, UOJING| ses “ gisnoyyTecy pue ayo ueity ‘pleampy SuLyy AOC one “ syaany Jayur AA Adis) eqO[D MOUTOR “ 95eUINI<] "Jase spesyerenbs ioe qajur A, Aoiry Jaqury, Aart) a Saany eT SUTRA Jajura, Aor) YOIMOTET FEUD SUCAN SuUIMAIgy] UOJING| gue “** OGOTT) MOTI X “ pIBVApy sury winuog wnuseyy oe suimoig uojing] “AJOure A ! ) part SSB1ey sapamc splosur yy os Koyresy cE ORiM ge XE) BAS ™** $90]V}0,] yvaty A\ yale] playryeeiry Tepsy playguregy sooy] SOOH e]VT y]eqpHorg, O23 SoM ae ead 5 cA isva ‘S 19}]SO,] UIvET ISOAA ysom DUG -aGyNojiay [NOG ysva ‘SOOPT Buoy 2 SIvG@) |< ac pref yoRjS Sspposuryy $90}P}0¢] vo Kayreg. | s}eQ suiaids +! -* "7 puvieezT MAN aE TNNS SYEQ) TJUTAY i aeeSUeocT nial sIvQ “a “ “a "- JESU ys aie zs IY A\ ysva ‘uapuedieyy yeas) s1eQ { eee eee yqnos oe JEOUA\ | “ yqaou ‘ydmes Aapiecy pooay }oOUuYy 913IVT splosuryy ) SAOAVS ! $90}10 \ ties =3509| 4°54 |(R.23°59| 33°91 (ee 3290) 5°80 : (kk. 21°42) (Ra oeea ae 3-77] | _pe| {R. 20°68 } | (ales ee a 413) | (R. 354) 18°80 \L. 10°66) ga (R. 3803 19 22 | \ lide, GOrG2) 2°43 | (R. 354 2025 | nee torts 3°46 (R. 2°32) 1028 ite Oxey| 2°62 (1. 20°44 | (2G 270 (R. 23°16 $197 (dee 288 3°34 (R.2771| 32°68 Mice oma 3:30. 4] i ong Lola ae [R692 ol anh CRAP IS = sal 1-94 | R. 3 15°03 I 0°46) 161 R. 258) 13°87 L.. 0°36 1°21 R.- 2°56) 18°17 ley Oil 1°56 R. 189 10°22 Ty (OF RE 1°51 R. 19°56 eet 65 seacee Hs ross Dressings. A. Ammon. Salts. Tons. 21 42 4°69 23:07 4°96 7 35 Zelel: 0°94 0°76 4 82 1°81 671 Duley 069 0°59 27 68 D7 54°17 193 19°65 | Rape Cake. |— | Ammon. Salts and Tons. 22°56 6°00 29°59 6°62 19 43 4°63 4°72 2°63 10°13 327 10°55 3°38 3°88 DAD, 28 04 257, 36 78 9°05 34 28 +°60 12°16 3°06 52 02 5°68 50°10 S| Sif 10 66 3°03 No ie in] rn SOD nor @ No Rape | Cake. 25°09 | 3°46 31°05 3°57 19°15 1°97 9°90 VS7F 1546 | 134} 19°27 1°38 748 1°23 Tons per acre in all cases. I~ LW a) 6 tS) N Od } QELS |} 6.0¢ | 9:8¢ 6.C€ “JAAD | *(sdo19 \|puz pur 4s]) TL6I-9S8T siead £¢ 10} eselaay | | AL dl Aches Lal 9.Z£ || 0.¢+ L.1Z | O.b7 paul] jou os Jae “Sun paedwiry 07 aC Lis Gea tle oe 1 T.E€2 |] $.9€ LeGTe Gch petty you sisi Se DOG eae oar a: sun paeAwiry 6l | Z.>T Cor Cz b.97 9.9€ | 6.¢Z I. paul, you MEEK tO SIEHGING Duy (UIseuoe IN ‘Epos jo ayeqdyns ‘ysvjog 8 £49 | 9-2 si! 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Ont 16.8) a pacar om) | mo | camo {} amo | ymo || Gao | samo wo | | i = *doag | “do1g || “doa “dor ; “dor for ae pug | a Bie | ee | TOL | ie dene | AS S16t ]__ EUS ; = pO 2 “SulAINULIY 101d | ‘esor sed ‘aioe ied ‘aioe sad gerne: PIPL | AV JO platy | Sey JOppxy OF > By TY OY aD dO) f “AOA “SSeulio ye Sie onan “XPLI acre in 1903, lb. to the 2,000 are > > 5- Mineral Manures in plots and Dung was omitted from plots 19 and 20. Up to 1914 the limed and unlimed plot results were not Ground lime was applied to the Southern portion (limed) of the plots at the rate of : 1907, and March, 1915. In 1917 all Potash and Magnesia were omitted from the and 18 separately given in the Annual Report, but the mean of the dures are given. ms From 1915 onwards the separate fi Average for 15 years 1893-191 two was given. (Cis 58 The Park} BOTANICAL COMPO- ; 1915 | Plot. Manuring. | Liming. Crop. | F & a | 58 | | 3 & Jie Ee | ee 2g eee | le ee 5 ae : EA ace eet Oh {| Nat toned ee | 52°52, 5°29 42°19 al ne 2nd |} 42°08 ; 11°49 | 46°43 | sy 2] ie arse Seats peer ceere {| Whole plot; Ist | 44°91 | 17°45 | 37°64 | ae ays ; sat ie | 2nd || 45°39; 8°87, 45°73 a eee paint eG: : Bea {| Not limed | Ist | 93°63; — 6°37 4-2 | Super. of Lime and Amm. Salts... l| ns | age 98°98, 0°24 07 ieee ; : ate {|} Limed ..- }:dist j/Omgsl .— 1°1¢ 4-2 | Super. of Lime and Amm. Salts... | by au | 2nd || 98°83} — 117 5-2 (S. half) Complete Minerals ; follow- { | Not limed | Ist ‘|| 79°07! 6°02 14°91 | ing Amm. Salts alone, 1856-97 ...|| Whole Plot *2nd | 59°70 19°32 20°99 6 | Complete Mineral Manure as plot7;/| Not limed | Ist | 51°38 33°79 14°83 | following Amm. Saltsalone, 1856-68 (| : | 2nd || 60°94 | 27°92 ' 11°14 a (| Not hmed Ist 60°85 | 24°76. 14°39 § 7 Complete Mineral Manure ... ne (| 4 | 2nd | 50°19 36°73 | 13°08 Soak ms - : {| LEmred> =: Ist 53°76 | 36°90.| 9°38 7 | Complete Mineral Manure ... “4 owe | nd |] 55°44 | 34°44 | 10°12 lt eee SPere: ae {| Not limed | Ist || 52°73} 11°00 36°27 8 Mineral Manure without Potash “| a 2nd | 44°24 13°88 | 41°88 2 . re ne {| Limed ... | Ist {| 50°54 | 22°43 | 27°08 8 Mineral Manure without Potash sh 3 . | 2nd 40°51 | 22°21 37°27 9 Complete Mineral Manureand Amm.{,; Not limed | Ist | 8939, — | 1061 Salts . as at + 2nd || 85°98; — {| 14°02 | 9 Complete Minerat Mecee ene iipeim edie. Ist || 98°40 014) 146 Salts . : ot) sF «- | 2nd ||97°72| 0°32| Tog 10 | Mineral Manure ee ithout Potash) and (| Not limed ist. | 98°38) — 1°62 Amm. Salts .. wae | nS | 2nd | 96°20; — 3°80 10 Mineral Manure (without Potash) and {)) eimted “| ilsta 989.64) —" | Om Amm. Salts .. oe Uy ‘3 eee 2nd ||99°00|} — 1°00 | 11-2 | Complete Mineral Manure and extra {| Not limed | Ist |}99°71; — 0°29 | Amm. Salts and Silicate of Soda (|) * ,, | 2nd ||9959| — O41 11-2 Complete Mineral Manure and extra{| Limed ... lst LOO'O;)) = = Amm. Salts and Silicate of Soda_ || rt aa: 2nd || 99°65; — 0°35 14 Complete Mineral Manure and Ni-{, Not limed Ist, 88541) 4°41 |) 7s ! | trate of Soda=86 lb. N U Ps 2nd |} 80°71 / 11°73) 75a 15 | Complete Mineral Manure as plot 7; ( Not li 1 ee: a Not limed [st || 49°77 | 38°94 | 11°29 following Nitrate of Soda apa: “ ond | 54°84 | 32° 74 | 12°42 1858-75 S00 Eee ae 19 | Farmyard Dung {, Not limed | Ist | 68°91 | 19°65 | 11°44) | Toe ee U e | 2nd + 58°80 | 33°67 | 7°52 | [i att t {; Not limed | Ist 76° 95 | 11°91 | 11°14 20 Farmyard Dung 7 | 2nd 73°81 | 14°98 | 11°20 |) * 2nd Crop was sampled from whole of plot 5 (i.e. 5-1 and 5-2). Grass Plots. SITION, PER CENT. | 1917. —— ee | ~ | , nh - , . b a z | 5 x |g u z | & é “Other Orders’’ consist largely of Plot. a@ |) te / oul «8 | we | ct & vo O's we | wv O-= ora BE/ 42/66] 58|/ 38) 56 | ee jl} ene ke ee es 3 a : 66°04 879 | 2517, | 43°96 | 5°53 | 50°51 | Leontodon hispidus and Centaurea 3 s— |— | — | ee |) nigra (very varied herbage) 6412 749) 28°39 || 51°44} 498 | 43°58 | | Leontodonhispidus, Centaureanigra, 4-1 > | — == || = = — |) and Plantago lanceolata = ey i ee Naa fe Rumex acetosa ss a 4-2 ee albead | Beds 5,9 Rumex acetosa and Galium verum 4-2 2 == |) a ee = nS | 2 . } 29 7°56 | 5 --49 ! apes | “86 | Ue | oe | se } Centaurea nigra and Rumex acetosa 5-2 74°08 | 17°42} 850 || 61°64 | 25°87 12°48 | ) Centaurea nigra and Achillea mille- 6 — — |/— jj — — | — |J folium 74°84 | 15°14 | 10°02 | 59°11 | 11°36 | 29°52 | Centaurea nigra and Achillea mille- 7 ——— = 5 See allie — | — |) folium coy aun May Be eMe ee a5 : _°* | pee ee | 8 | re21 | mes | Centaurea nigra 7 69°00 8°27 | 22°73 || 48°31| 2°69 _49°01 | Centaurea nigra and Plantago lance- 8 _— | —- |} => | — — |) olata 71°34 7°50) 21°16 58°70-| 4°70 | 36°60 | | Centaurea nigra and Plantago lance- 8 ees i -— | i—- | i— |) olata | a | eet Ol | Rumex acetosa ose Spe oor 9 eS) | — } 83283) — | 1°72 | | Rumex acetosa and Achillea mille- | 9 eta i | —— jo — |) tfolium a — fi o2-12 “Ste $y adr otey __ | aS eee | 23.18 a: oe Rumex acetosa pc Soc AB 10 | | — — — Q* —- i | ee | ee | | Y ; Rumex acetosa = aes Bo 10 | 4~ | } | 100°0 Se en | 7a 11-2 m3 6) |) — (6is||| = — |) Heracleum sphondylium and Rumex | 11-2 : The eae = | } acetosa 83°75 | 6°68 | 937\|.— | — | — |) Taraxacum vulgare, Anthriscus syl- | 14 | | ellen avestris | as | — |i 79181 15:74! 14-97 | } = — Pee ||| ey arid aes > Achillea millefolium ... 4 = 15 | | | | 74°46 19°20) 6°34) 68°7 | 21°38) 9°92} \ Anthriscus sylvestris, Rumex acetosa, } 19 il Sioa silt | - | J Centaureanigra, Achillea millefolium 81°83 | 12°03 | 6°14 |! 66°13 | 24°95| 8-92 | Anthriscus sylvestris, Centaurea 20 = = i= amet) | | | nigra, Achillea millefolium eS oe 2h See =) Lae i ace ms mF = 2nd Crop, 1916, was very small and was not sampled for Botanical Analysis. 2nd Crop, 1917, results not yet available. Plot. NotTeE.—The top portion (aati half) was fallow in 1914 owing to the weedy The bottom portion (eastern half) was fallow in 1915. 60 Ww heat. Broadbalk F ield, 191 17. Produce. 1915. 1916. 1917. / (Top portion). (Bottom portion). (Bottom portion). | Dressed | Dressed Dressed : Average Grain. | Straw Grain. Straw Grain. Straw icon hn riag SS — | per, [apes er = Yield Weight | dels Yield Weight eee Yield Weight p aie Gan | Straw per per per per per Acre. Bushel. Acre. _Bushel | Acre. Bushel.| P24 Acre. |Bushels| Ib. | cwt. | i) Bushels “Ib. | ewt. |/Bushels) Ib. | cwt. || Bushels| wt. 3227) 6620) 83 7250|| 25.3 4) Ola0 | 41°3 || 160) o7s6 14°8 I) Sar 34°8 12°1 | 62°3 | 12.4 | 164] 610] 15:8] 82) 599) 55) 126) 103 155 8))) 6216") 158 18°5 ; 60°2 | 208 9°9'| 60'85|) 7 eae 2057 |PO2Z 0 Ait 1 25 4 60rSa| etek 181) ‘6bSt ais A aa la 33,9) | 624 || 3455 | 31°3 | 6073 | 40:9) |) 2355n 60 Se ehes | 321 | 32°9 37°5 | 61°5 | 40°9 | 31°7 | 60'5 | 42°41) 303 | 959°7 125 Seed S035 6255) | 3272 29°2 | 60°6 | 35°57. 20 Galeaaes 188 |) — | — LOs3; |) "6284; |) ZO: 18°5 60°3 || 2656. ||° 138] ayia oe | 200 |} 18°4 2325 | (GIs6nl Aveo 13°6-] 59°3'| 24°9 || T4569 S717 es ae ee 3370") (61538233 22,5) OORT TA SS56 19°O0)| 58255] S72 ees 28-0 33°2 | 60569) 38°04) 251) |) 6025355 29°8 | 60°73 | 2259 3h0;| 3i°5 3095") (G06 eS156 214 5) 591643229 21°2 | 59°7'| 156) 28 3/8P28:0 19°0 | 60°6 | 23°6 || 21°8 | 60°6 | 27°8 || 2750") “GOS. 20st Ae Oa 29 7 SUS a Glee a5 26:0) 60n soe 29-7 1 OSe7 ees = == 16:17) CLS fh Leis Zik 7 | SO Lalas see Le Tt 5 9r8: 79 || 29°99 | 29°5 241 Glebe 2850 196} 610 204 230°). 6O°Se aia 149} 13°0 25°55 | 6179) 27°3, | 20°35) GIRO e238 ea eel aiiieet OD Sa eoster eo. 7 16°9" |, 6270) |, 2371 = == = a = — a a condition of the field. * 20 years, 1893-1912° W heat. ESR E 1eld a 17. Manures. Plot 1915 and 1916. 1917. 2, Feseaiara Manure Farmy ea Manure | 3. | Unmanured 3 ... Unmanured 5 Complete Mineral Manure ... Complete Minerals (Potash omitted) 6 As 5, and single Amm. Salts ... ... As 5, and single Amm. Salts 7 (\As5, and double Amm. Salts ... As 5, and double Amm. Salts 8 As 5, and treble Amm. Salts . As 5, and treble Amm. Salts 9 As 5, and single Nitrate Soda .. As 5, and single Nitrate Soda 10 | Double Amm. Salts alone . Double Amm. Salts alone 11 As 10, and Superphosphate ... As 10, and Superphosphate 12. As 10, and Super. and Sulph. Soda... As 10, and Super. (Sulphate of Soda omitted) 13 As 10, and Super. and Sulph. Potash As 10, and Super. (Potash omitted) 14. As 10, and Super. and Sulph. Magnesia) As 10, and Super. (Magnesia omitted) 15. Double Amm. Salts in Autumn and Double Amm. Salts in Autumn, and Minerals Minerals (Potash omitted) 16 | Double Nitrate and Minerals... . Double Nitrate and Minerals (Potash | omitted) ), we -.},. {Minerals alone (Potash omitted or 17 ] Minerals alone, or double Amm. Salts | double Amm.Salle'aleneeng alee 18 alone, in alternate years Le eae 19 Rape Cake alone sac Rape Cake alone ) 20 Mineral Manure (without Super. ) and Sulphate of Soda, Sulphate of Mag- Amm. Salts nesia, and a of Ammonium NoTeE.—No Autumn manures were ence for the 1915 crop: " dressings were given in the Autumn of 1913, but not in 1914 as that half of the field was ERRATA.—Plot 19, 1917, for ‘‘Rape Cake only then left fallow. In 1916, Sulphate of Potash being short, the dressing was in each plot made up with the required amount of woodash. there being none applied in this year. ’’ read ‘‘Rape Cake omitted,”’ 6] “JsOl SOANHFY WE ld y IGT TLS Ssavad OF (7) “LIGE —-t9RT “SIVAN QF (1) 0.e1 | 0.86 | ¢.81 |] z.¢z | z.¢6 | .¢¢ | £61 z.£S | € 67 ‘i i tk — it 5 | €.01 | O.8b | €.FT || b.0e | 8.€6 | 8.S€ | S.L1 | Tc | €.0€ ATUO BPOG JO aVBIN IS JO ALAYIN | | | | | Gh | O8h his. 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VAGINAS INGE i SSHENVO) S16) [061 AuIs asnuep, ON *(S}OTq 07LJO A[1aWUl410}) Play Soop] 63 Little Hoos Field PLAN OF ROTATION PLOTS Arranged to test the RESIDUAL VALUE of VARIOUS MANURES in one, two, three, and four years after their application. Produce per acre. H eeu Aries Beat) 1916 ee Season). piace ean Mangolds. Neat. Glover | | Ae Dress-|_ To a ee 5. Roots. Leav’s pola oft, Shea pce Bo ae Total. | | Tons. | Tons.| Tons. Bush. ecwt. Ib. cwt. | cwt. | cwt. ph ) Control ... 5°36|2:03| 739'|| 207) 191 3492 \\ 19°7 | 22°2| 419 2 a 9°44 |2°16!11°60 284 304 5292 | 38:2 | 274 | 65°6 3 | Dung (ordinary) | b | 11°66 | 2°25 | 13°91 | 26°8 26°6 | 4766 | 31°7 | 27°7 | 59°4 4 16 tons peracre | c | 9°37) 1°97 | 11°34); 25°7 | 25:1 | 4520 || 26°2°| 26°6 | 52°8 5 ) ld 13°53 2:92 16°45 || 27°6 | 28°9 | 5040 || 31°9 | 26°1 | 58°0 | | B1 \| Dung (cake fed) a@ | 9°52|2°44 11:96 340,341 6003 38°74 27°2 656 2 || Control ... ee | 778/220 | 9:28) 27°3| 17°41 3324 || 19°1 | 21°7| 40°8 ie ae : (b | 13°00 | 2°58 | 15°58 || 27°2 | 28°3 | 4952 || 34°3 | 26°9| 61°2 4 eee fea) c | 11°81 | 2°47] 14°28 || 26°6 | 27°1 | 4772 || 35°8 | 2671] 61°9 Et) | P (ad | 15°27 | 5°02 | 18°29 |! 29°5 | 29°6 | 5135 || 32°7 | 26°9/| 59°6 |C 1)\| Shoddy956lb.per{a@ | 5°:17)199| 7°16|| 156, 147 2668 | 17°6 | 24:0 | 41°6 | ae | ACTE. sc. 2 Bb | 6421/2315) 8°57 || 11-41 10°6| 1961 || 18°6 | 21°7 | 40°3 Meese Control”... .:. 687 |2:39| 9°26 || 16°5 | 12°6 | 2523 | 20°7 | 24°6 | 45°3 i cA Shoddy 956lb. per {ec |. 7:23) 256) 9°79|| 18°6|13°9| 2800 || 19°7 | 25°1 | 44°8 3) | AGCKEL ac. mee Gd 8°71 2°79) 11°50} 20°3 | 14:1 | 2923 || 17°6 | 26°6 | 44°2 D1 \| : (a | 490|1°60| 6°50 || 220/204, 3801 | 19°4 | 274 46°8 } 2 | Grane 776 tb. ver ) 4 | 737|1°96| 9°33 || 17°11! 13°0| 2605 || 18°6 | 24°0| 42°6 | ea z ster s|, 35200) 41 8-2 | 11-1 | 2452 || 21°7 | 25°6| 47°3 | 411 Control ... | 6-64|2:20| 8:84 || 17°38 13:6 | 2734 | 20°4| 27.2) 47°6 ee Guano .. ... @ | 8-39|2-69| 11:08) 13°3/12°8| 2348 | 19°7 | 29'0| 48°7 E41 \ fa | 5°30)181) 7°11) 184 155 2986 | 186 25°6 | 44-2 Peecel i isape: Cake 1036! b 7-80 | 2:03 | 9°83) }| 18°6| 13°8 | 2768 | 18°9 | 26°1 | 43°0 fees -f| Ib. per acre ... | c 784 | 2 19 | 10°03 || 20°9.| 12°3 | 2749 || 19 7 | 24:3 | 440 et | d 8°71 | 2°95 | 11°66 || 14°6 | 13°0 | 2466 || 20°2 | 28°2 | 48°4 Se)/i\Control .:. ae 4°70 | 162| 6°32\| 10°1 | 12°0 | 2084 || 24°1 | 28°5'\ 52°6 | ‘ Za | Control ... ae | 4°80\2°09| 6:89)\| 117! 11-4] 2419 | 14:2! 269|\ 411 age) a | 7°90 | 2°29 | 10°19 | 19°9 | 14.2 2906 | 1871 23°8| 41°9 3 Superphosphate b SOL | 2 35.| 107864) 17° 7 | 13°9| 2729 || 16°5 | 25°9 | 42°4 4 600 Ib. per acre: c | 7°36! 2°42] 9°78 | 203/162! 3165 | 19°9 29°3| 49°2 8 (a | 723/211) 934/196 16:0) 3098 | 230 30'8| 53'8 iG 1 )| Bone Meal4301bi {a} 6'24| 2°23) 8:47) 19°7| 15°1 | 2980 | 14°7 | 29°0 | 43°7 2 per acre meee 1 AG 70)) 2°32)|) 9°02:122°0 | 16°5| 3235 | 15:2 | 29°3 | 44°5 i 3 Control ... Ne 5°90|2:°08| 798204 16°3| 3172 \ 14:7 29:0|43°7 4 Bone Meal 430 1b. ! c 5387 (25061 -7°93)\| 22°0 |} 176 | 3430 | 17°8 | 29°5 | 473 5 per acre nan itt ia! 4°41) 1°86 6°27 }| 23°6| 187} 3680 || 18°9} 29°3 | 482 Hl | (@-| 9°0111°99| 11°00 | 24°1 | 17°6 | 3528 | 24:3 | 24-6 | 48:9 2 Basic Slag 600 1b.) 6 | 10°34 | 2°25 | 12°59.|| 26°5 | 19°5 | 3867 |} 21°7 | 23°8 | 435 heats per acre ... | @ | 10°05 | 2°13 | 12°18 || 27°7| 199 3921 | 23°3| 22°5| 45°8 a d | 856/|1-93| 10:49 || 26°5| 19:7. 3874 || 21:0 | 22°8| 43 | 5 | Gontrol ... Ges TT 8°34 | 246 )19°3\ 3734 18°'0| 236) 419 « received its dressings in 1912, 1916. c received its dressings in 1910, 1914. 6 ve 1913. d os ve 1911, 1915. NOTES AS TO MANURES. The five plots of Series A to E which deal with The five plots of Series F to H dealing with Phos- nitrogenous manures received cross dressings as phatic Manures received dressings as under :— under :— 1904 1 cwt. Sulphate of Ammonia. 1904 3 cwt. Superphosphate per acre. 1°05 ditto. 1906 3 cwt. Sulphate of Potash ditto. 1906 2 cwt. ditto plus 3 cwt. Sulphate of Potash. 1907, 1908, 1909 3 cwt. Superphosphate. each year. 1907 1 cwt. Sulphate of Ammonia. 1911 ditto plus 200 Ibs. Sulphate of Potash, but 1908-10 ditto. no cross dressings have been applied since. 1911 ditto plus 200 lbs. Sulphate of Potash. 1912 l cwt. Nitrate of Soda. 1914 1 cwt. Sulphate of Ammonia. 1915-16 ditto. Clover was grown over the whole field in 1917; no manures applied in Autumn 1916 norin Spring 1917 Thirteen tons of dung per acre was used on A and B for 1916 crop. Figures in italics denote the unmanured plots. The yields on the plots to which the manure was applied in a given year are printed in heavy type. In 13th season plots A and B were sown Nov. 24, 1915. C to H were sown Feb. 17. 1916. Riis 64+ Long Hoos Field. Green Manuring. 1914-15. WHEAT — Produce per Acre. [oe roe Dung 10 tons a | No Treatment. per Acre. Mustard ploughed in) a oat: Z Grain. Straw. || Grain. Straw. | Grain. Straw. | a] Bushels. | ewt. | Bushels. cwt. Bushels. | ewt. . ; A: . . “Zz 9 “Oo | Ce ~ NeAEGRGIS 144 | 146 || 164 | 20°50) | 20@eersaes Superphosphate 3 cwt. per {| — — 18°2 18°8 206'9 26'0 ACECy ma. se Be eel] — — 19°6 19:0. || -29%. |) 2678 | Superphosphate 3 cwt. and = ( ae - aD: ree aie Aaa Nitrate of Soda 14 cewt. per. 2 eee Abe ae poke ae acre ... sf ce aa | ae * gaa | name Meera Se es SWEDES—Tons per Acre. No pe 1G Mee | Clover Trifolium | treatment. | hens ploughed in, Plovshed in. ploughedin.| _O Ci... 7 \. 2 (| fore = 8°4 8-2 | 103 | No artificials somata Cees} = | 76 — ( = 12°0 10°6 10°7 11°0 Superphosphate 3 cwt. per is me ss Sl ae | acKremecr ba els goo = | i 12°9 | | - 12°7 | | = isy3' | | Superphosphate 3 cwt., Sul- (| 11°4 74 | 70 C0 ay S295 | | phate of Ammonia 13 cwt. /) 133 9°3 12°9 110 L253 per acre Nie eulsins 12°6 Dunn SEE ploughed in January: fairly free from growth of weeds. Winter Barley.—Ground well covered but not much bulk. Clover.—Ground well covered but not much growth. Trifolinin.—Most of this died during winter, but there was a dense growth of annual weeds; not much bulk. Barley (after Swedes). Long Hoos Field, 1916. linus 10 Tons| Mustard | Red Clover | Rape NoTreatment) per Acre ploughed in | ploughed in | ploughed in Trifolium | (Grain Straw|Grain Straw Grain Straw Grain Straw Grain Straw Grain Straw |Bush | cwt. |Bush.| cwt. | bush. cwt. bush. | cwt. | bush. | ! | c -| rh (| 25.7 147 41°7 | 21:1} 34°9 1941 | 36°3)| 1997) S4e7) ye nesses fat70 No | 32 ANT 44552 | 2452) SOOM a esis | 18°4: | 3257 1 WSr6 3652919" 5 artificials ~} 37°4 | 19°4] 41°5, 21°9 | | 3659 | 18°2'|40'S | 21°0 | ( 33°7 | 19°6 | Super- | Ss se Greta eee | 37°7 | 19°3 |.30°54 20°69) 2557 SSeS 2On, | phosphate || — | — | 46°7| 264 | 3 cwt. per || — | — | 333] 21°6 acre ( — Ses Oe 7 i|, Ales) Super- | prosper | 48°7 | 26°6 | 47:0 | 32:2 | 52°6 | 29°1 | 38°4 | 28°8 | 40°0 (27'S | 45°5 | 29°4 | - Per || 49°8 | 27°5 | 461 | 33°9 | 51°6 | 29°8 | 53°7 | 29°6 | 51°7 | 28:8 |. 53 3| 28:9) acreand | 55°0 | 20°6 | 47°0 | 31°7 | Sulphate of | 57:3 31°8 361 | 31:0 | | | Ammonia || 55°1 | 30°8 | | | ) |e Cwheper aie aes ee acre | | } = | ee ae | CROP YIELDS FROM 65 DUNG STORED IN DIFFERENT WAYS. Yield of Potatoes manured with bullock dung, Ww est Barnfield, 1915. Yield of Potatoes in Tons per Acre. Plot 1 Mean Percentage increase over the unma- nured plots : Weight of original dung, tons per: acre | No Manure, All "95 ‘18 ue or Loose heap under cover. 9°29 8°36 10 tons of stored manure per acre, stored in heaps for three months. ror yInpact heap under cover. 9°00 76°00 12°96 Great Harpenden Field, 1916. Loose Compact heap in | heap in the open. the cpen. 8'18 7°61 8 00 7°18 7°89 TPS2 8°02 7°38 57°00 44°00 13°68 12°05 Yield of Rivetts Wheat, manured at same rate from same heaps as above, six months later. eset —— Dressed Grain per acre in bushels :— Plot 1 34°6 37°3 400 6 ihe i/ 73 BYAG 362 37°8 5°9 357 3 34.6 4 311 Mean 33/2 36°7 38°9 35°8 33° 7 Weight of Grain per bushel in Ib. : Blot ls. ae ope 56°0 opel Sons s}s)0) 561 By onc Sars) 3)3)) 55°0 569 555 chee 56°0 | 4 59/05 || Mean 5573 DD Doe 560 55°8 Straw per acre in cwt. :— IPAS Gee 261 32°0 S176 24°1 29°3 Oe Be 24°8 30°9 31°4 30°7 aL 3) 28°9 4.. 207. Mean 26'°9 314 3155 Diet 30°2 Total Produce per acre in Ib. :— Plot lL .:. 4975 5748 5893 4760 5168 aie 4635 550 5690 5610 5560 3... S275 4... 4885 Mean | 4943 5649 | 5792 5185 | 5364 Percentage increase in grain over the | | unmanured plots .. : | -- 10°5 Wa) 78 LS 66 Residual effect of Dung stored in different ways. Manure applied at the rate of 20 tons of original manure per acre for Potatoes in 1916, followed in 1917 by Wheat without manure. Foster’s Field. | Compact ie Pe _ Compact heapinthe| Compact , POTATOES. Ma heap in the open, — heap under wWlanure. open. covered | cover. ; with soil. | Weight of Potatoes. ane per Acre A033 3°65 3 91 | 4°00 , Percentage increase over Unmanured | |) “Plots eee cee eect we — toe | ag 52 WHEAT. | | | | Weight of Grain per Acre ... lb. 1349 1637 1572 1752 | | Weight of Straw per Acre ... lb. 1870 Miele | 19657 eel | Weight of total Produce per Acre lb.| 3219. 3772... > ‘3530 see eee | Bushels of Grain per Acre ... 19°95 24°55 23°23 25°55 Pecos eon increase over Unmanured oss | 23 | 16 28 EXPERIMENTS WITH VARIOUS NITROGENOUS MANURES. Potatoes. Great Knott Wood Field, 1916. — = SS Weight of | Plot, | All plots received per Acre: Dung, 10 tons; Superphosphate, oe per | | 2 cwt.; Bone Flour, 23 cwt. “Acre | : | | Additional Manure per Acre :— Tons. | 1 Recount { 5°45 ike ; Nitrolim, 1 cwt. 5°20 / 3 No additional manure ee ese oy. ace ve Bae 4°80 i Iphate of Ammonia, 1 cwt ‘ a | 5 j Sulphate of : onia, 1 cwt. l 4°54 | | . oa | ona (Se. Knott W ood Field, 1916. eel se 5 receiv aa per Acre: Dung, 10 tons; | No. of | Weight of Plot. | Superphosphate, 2 cwt.; Bone Flour, 13 cwt.; | plants per | produce per | | Salt, 14 cwt. | - Aere.” |") Wires 4 | Tons. 1 | | Received an additional dressing of Nitrolim at | 10600 | 13°04 2. |) 1k cute per Acres’. a zee A | 12300 | 14°64 3. | No additional manure... a a Sia 11800 11°52 - | — - Savoye e Little Knott Wood Field, 1917. - | N E ae Plot. | All plots.received per Acre: Dung, 10 tons, and] | Weight per — pocie coca 2% cwt. Acie: | Acre. | | ‘AdGiaenal Meaure per pn — Tons. {dbs | Sulphate of Ammonia, 2 cwt. es ia 10380 | 15°24 | 2 Nitre Cake Sulphate of Ammonia, 2 2 cw. el 10450 | 14°59 1 es | No additional manure os: ae ese 10160 11°56 4 | Decomposed Cordite, 275 1b... esas 11350 |: “sie | 67 EXPERIMENTS IN SOIL MANAGEMENT. CHALKING. Sawpit Field. ik Chalked in 1913. 1914, Oars (Grey Winter —Yield per acre 1915, CLOVER—Yield per acre as Hay 1916, WHEAT—Yield per acre Dressed Grain bush. Weight per bushel Straw per acre Dat Total Produce per acre ... 1917, Oars—Yield per acre Dressed Grain Weight per bushel Straw per acre ... Total Produce per acre Not Chalked. 20 fends. | so‘toads 7 per Acre per Acre | Carted (1).! Dug (2). - ' | bush. BUS | 411 — 44'6 | cwt. 35°38 | 39°2 20°2 18°6 ge78) 3012.) 242 | 313 lb. 62:0 | 63°3 | 624 | 63:0 cwt. 40°3 35/0 30°5 35°5 lb. 6878 | 6130 | 5163 | 6246 | bush.| 29:7 | 271 | 236 | 283 | lb. 33°3 364 | 368 35°3 | cwt 22°8 22:9.|. 23:2 23°6 | Ib. 3842 | 3804 | 3675 | 3895 | 1913. 1, Chalk carted Baits ee seadoenl New Sewage beds, February. 2, Chalk dug on Sawpit Field, November, 1912, to March, 1913, and spread as dug. Journal of Board of Agriculture, October 1916 (Vol. XXIII, No. 7, page 625) givesa detailed account of the method and cost of Chalking. Great Harpenden Field. ' 60°8 t 20°1 W = West portion of plot. | 1914. || 1915. Sita. | BART EY: WHEAT. 53 (Plumage Cross). | (Squareheads Master). z Sc, Stee as beiaceenanliesara oe 2 i Dressed | Dressed ls Grain. Straw ane i Grain. Straw| Total 4S : per produce = See er produce (sie mel Hisere Ane: | hee: Yield Weight | Acre.| Ame. | per Acre. Bushel., | Acre. Bushel. | Acre. || Bush. | Ib. | cwt. | Ib. || Bush. | Ib. | cwt. | Ib. es () W319, 55°6 | 17:0 | 3788 || 20:2 | 62:0 | 19:2 | 3584 | Unchalked | 9°3 ( E 40°5| 55°9 | 21:2 | 4784 | 21:6 | 61°5 | 23°7 | 4228" | Boca cate |ben {| W319] 359 | 188 | 4025 || 21-7 | 62-0 | 20°8 | 3859 : pe oy laa : Gee Rene) | E359 54°9 ie) 2X2 17°6 | 62:0 | 201 | 3525 | WHEAT. BS ak Xa 1916. _ (Wilhelmina). WINTER OATS. l(a 9-9 | 90°5 | 3661 Unchalked | ae 59°5 | 39°7 | 6631 23] 422 | 205, Ane . ‘ aa) 40°7 | 43°0 | 26°3 | 4825 | Chalked in 1913... | 27 3-| 59:0 | 37°3 | 6100 \{363 44 | 250 | 4553 1917 WHEAT. | WHEAT. : (Red Standard). | See s Master). a wae m ‘ j ' | (| 242 | e12| 187 | 3809 | 22:2 | 59:7 | 17-9 | 3539 Ai el ti) 249.1 61:2 | 184-4 3801 || 1971 | 58°8 15°9 | 3079 Chalked in 1913 ... =i) a7 232 | 60°0 4138 180 3643 E= East portion. EXPERIMENTS IN SUBSOILING. Potatoes. All plots received per Acre: Dung, 10 tons Superphosphate, 2 cwt. GE Bone Flour, 24 cwt. hie ed oad | Sulphate of Ammonia, 1 cwt. ; | a 7 ; zt Tons. z f Not subsoiled ju ! aoe 3 | } Subsoiled for this crop + Ald Great Harpenden Field. | 191490 | ee 1995. - 4 [Ae aeieae ater: | POTA- q | “ee ; | WwHRAT “TORS | HEAT. |) WINTERS | eames | (King Ed- | ~ Sausxebeadis OATS. heads ward VII) | . . Master). Te 1,2) at) oe | | | Dressed Grain per leSub=s 974 | Acre Bus. | 20°3 | 19°4 | 16°4 || 30°5 | 30°9 | 29°3 || 19:0 | 21°5 |soiled| (mean | Weight per Bus. lb. | 62°0 | 61°8 | 61°3 || 42°9 | 43°6 | 43°8 || 58°5 | 59°1 | < | fe) p | ; | | in | of 4 ||| Straw per Acre cwt. | 20°8 | 18°8 | 21°2 || 20°9| 211 | 23°0 || 16.2) 179 | 1914 | plots) | Total produce per | | | | | Acre Ib. | 3775 | 3478) 3541 || 3808 | 3863 | 4075 || 3123 | 3450 | | | | Dressed Grain per | | i | Neral Acre : Bus. | 19 (Ss sys 7a 29°4 S353) 220419 1 sub. |, ©9 .4|| Weight per Bus. Ib. | 61°8 | 62°3|62°0|| 422 | 45°0|| 59°7| 588 eeieg (mean) || Straw per Acrecwt. | 21°0/163]15°8]| 20°5 19°5 || 17°91 15°9 | | 1 Total produce per | | / | Acre Ib. | 3709 | 2938 | 2788 } 3661 3850 || 3539 | 3079 zi =- eee — | Great Knott Wood Field, 1916. Weight of Wheat after Fallow (without Manure, 1851, and since). Hoos Field, 1915, 1916 and 1917. Dressed Grain | “(| Weight per Bushel Straw ... ace | Total produce cwt. per Acre Ib. per Acre ... 1915. 1916. 1917. ; , {Yield—Bush. per Acre | 711 $°8'|" 66 Ib. | 59:8 | 60°2 | 59°4 ; 84 70h) Sate 62) |). 47a e346 Average | 6l years, | 1856-1916. | Fae | aa 15°6 o9%9 134 2477 I 69 COMPARISON IN VARIETIES OF WHEAT, 1917. Great Harpenden Field. | Red Standard. | ‘Squareheads Red Marvel. | | Master. Dressed Grain per “Acre Bush. 24° “2, 249 | 22°2 Wig y\- 252 28°3 Weight per Bushell ... Ib. 612 61°2 59°7 58°8 59°3 60°6 Straw per Acre ... wen TeWte 18°7 18°4 17°9 159 19°5 22D, Total produce per Acre lb. 3809 3801 | 3539 3079 3830 4354 METHODS of SOWING WHEAT after POTAT OES. Lana Bough ed | W he: it Drilled | Wheat then sown ploughed in po . | Produce per Acre. inusual way | __after being | potato | . | Seed | De- tilth, not Seed Broad- Das broad- (posited plough'd x. alin ay -drilled. | casted. by drill. casted. Great Harpenden Field) Dressed Grain Busi | 24716) 2550)" | 240 | 24°6 | 23°4 LOU'S. | Weight per Bushel ... lb. | 62°9 | 61°9 | 62°6 | 62°8 | 62°6 WHEAT. Straw per Acre Cw ails | *23:4 | 19°7 | 214 | -20°3 _ Squareheads Master. Total produce spp lilo | 4084 | 4329 | 3855 | 4121 3898 : on Fj Dressed Grain Bush. | 46°1 | 42°99 | 369 | 40°4 37°9 pe cee een Field, | Weight per Bushel ...lb. | 59°5 | 59°4 | 59:1 | 59°4 | 59°4 | ee Straw per Acre cwt. | 344 39) Reyer i te ya | 19°8 Bo ets WHEAT. Total produce so! sy | 6722 | 6634 | 5479 | 6088 5690 as at lh s. {}. 239 | — | 13°8 - Dressed Grain Bush. i] 2571 a. 11:0 = Foster's Field, ee : {| 60°5 —- 60°0 — — 1917. Weight per Bushel — lb. 60°8 oe 59°83 | — a WHEAT. Siew Gore: Rete | 2318 == 14 ~ Red Standard. gia sa pb Se tk 2270 — 76 — P 2 {| 4286 = PAD | = Total produce lb. 1| 4124 1588 = a” PLOUGHED UP GRASSLAND. New Zealand Field, 1916. This field had been pasture land for 8 years and was ploughed up in autumn of 1915 No manure was given. ~ Produce Ca Produce per per ee Acre. ees BEE a —— Ss _ Acre. | ‘ 3 Tons. Tons. Potatoes—'‘ King Edward"' 34: Mangolds 12°25 “Dalhousie”’ 1°07 A 8:98 oo failed, the seed being taken by birds Yield per Acre. | W eight p per *¢ Bush. | Weight per Acre. I otal l roduce Pi. ab Grain. | _ Grain. i Straw. _ f ver Acre. | | | Wheat* aes ..-| 1441 bush. 56°3 Ib. 26'1 cwt. 4011 Ib. Peueyeoeess =) 2f6 bush. | 55°0 lb. 20°9 ewt. 3981 Ib. Winter Oats a] tone bush: 402 |b. 30°9 ewt. 5553 |b. | aia eat o7sOeibush. | 37'0 lb. 21°5 cwt. 3957 lb. “1917. —Bar ley was sown over ae whole fare End gave a yield cof 24+°8 bush, per acre. * Crop attacked by binds: Lawes Agricultural Trust TRUSTEES Right Hon. A.J. Balfour, P:C., Fok:Se fie: J. Francis Mason, Esq., M.P. Professor J. B. Farmer, M.A., F.R.S. COMMITTEE OF MANAGEMENT Sic]. He Ehoreld, Bart. ee: (Chairman). Prof.. H.. BE. Armstrous, espe D.Sc.,F.R.S. (Vice-Chairman). Prof. J. B. Farmer MAG Fo RS- (Treasurer). Prof. R. H. Biffen; MieAs ERS. Dr. H: T., Brown, ee ae ee S. U. Pickering, Esq.,M.A.,F.R.S. Dr. A. B. Rendle, D.Ser, Fi Bes. Dr. J. A. Voelcker, M.A., Ph.D. The Incorporated Society for Extending the Rothamsted Experiments in Agricultural Science MEMBERS OF COUNCIL His Grace the Duke of Devonshire, P.C., G.C.V.O. (Chairman). J. F. Mason, Esq., M.P. (Vice-Chairman). Prof.- Hi. . Es Axmstrons, ie oe Fikese Prot. |ReH. Bitten, NeA., hese Dr... T Brown, Piss hikes: The Right. (dion: Sir “john, ae Brunner, Bart., P.C. The Most Hon. the Marquess of Lincolnshire, K..@., P-G: Prof:-J. B., Farmem McA] EF Res: (Treasurer). Robert Mond, Esq. Capt. J. A. Morrison. S. U. Pickering, Esq.,M.A.,F.R.S. Sir W. S. Prideaux. Marlborough R. Pryor, Esq. Dr. A. B. “Rendle, Mea. sc. Ine T. H. Riches, Esq. Sir J. H. Thorold, Bart. Dr. J. A.. Voelcker, M.A., Ph.D. J. Martin White. Esq. E. J. Russell, D.Sc:, F.R.S., Hon. Secretary. i Subscribers and Donors to the Rothamsted Experimental Station The Goldsmiths’ Company (Endowment for Soil Investigation) J. F. Mason, Esq., M.P. (The “James Mason” Laboratory). His Grace the Duke of Devon- shines ac., G.c.V.O. The Kt. Hon. Sir J. T. Brunner, Bart., PC. The Marquis of Salisbury, P.C. The Rt. Hon. Viscount: Hampden. The Rt. Hon. Lord Iveagh, K.P., GeGeVeO. The Hon. Rupert Guinness, C.B., C.M.G. The Rt.Hon.Lord Mount-Stephen. The late Sir Julius Wernher. Lady Wernher. Lady Gilbert. Sir Charles Bathurst, K.B.E. i. kuiches,, Hsq., M.A. Dr. Rudolf Messel, F.R.S. Otto Beit, Esq. The Rt. Hon. Lord Rhondda. W. B. Randall, Esq. Rt. Hon. Viscount Hambleden. Alfred Palmer, Esq. A. Douglas Pass, Esq. Mrs. Hugo Miller. Miss Margaret C. Miiller. Marlborough R. Pryor, Esq. Robert Mond, Esq. W. Morrison, Esq. H. Tylston Hodgson, Esq. Miss E. D. Coats. J. H. Morrison, Esq. Sir R. A. Cooper, Bart., M.P. A. Brassey, Esq. Sir Beville Stanier, M.P. G. Stephenson, Esq. Messrs. Sutton & Sons. Dr. J. Augustus Voelcker, M.A. Sir George Barke;y. J. Martin White, Esq. Federal Government of Canada. Trustees of the Illinois (U.S.A.) The Government of New South Wales. The Surveyors’ Institution. Royal Dublin Society. The Grocers’ Company. University of Auctioneers’ and Estate Agents’ Institution of the United King- dom. Royal Agricultural England. The Chilian Nitrate Committee. The Potash Syndicate. The Sulphate of Ammonia Com- mittee. Society of The Nitrogen Fertilisers, Ltd. The Clothworkers’ Company. The Gaslight & Coke Company. Messrs. Brunner, Mond & Co. Capt. Clive Behrens. J. F. L. Brunner, Esq., M.P. Messrs. Ellis & Everard. Sir Eustace Gurney. A. B. Holinsworth, Esq. Messrs. W. B. Keen & Company. H. Mellish, Esq. Henry S. Nunn, Esq. Hugh E. Seebohm, Esq.