A6RIC. DFfL 
 
 
LA WES AGKICULTUKAL TRUST 
 
 Rothamsted Experimental Station 
 
 Harpenden 
 
 Guide to the Experimental Plots 
 
 PRICE - ONE SHILLING NET 
 
 LONDON 
 JOHN MURRAY, ALBEMARLE STREET, W. 
 
 1914 
 
OF THE 
 COLLEGE 
 
 LAWES AGRICULTURAL TRUST V^^ 
 
 Rothamsted Experimental Station 
 
 Harpenden 
 
 Guide to the Experimental Plots 
 
 1913 
 
 PRICE - - ONE SHILLING NET 
 
 LONDON 
 JOHxN MURRAY, ALBEMARLE STREET, W. 
 
 1914 
 

 COMMITTEE OF MANAGEMENT 
 
 Sir J. H. THOROLD, Bart., LL.D. (Chairman). 
 
 H. MtJLLER, LL.D., F.R.S. (Treasurer). 
 
 H. E. ARMSTRONG, LL.D., F.B.S. 
 
 R. H. BIFFEN, M.A. 
 
 H. T. BROWN, LL.D., F.R.S. 
 
 J. B. FARMER, M.A., F.R.S. 
 
 A. B. RENDLE, D.Sc, F.R.S. 
 
 J. A. VOELCKER, M.A., Ph.D. 
 
 DIEECTOE 
 E. J. RUSSELL, D.Sc. 
 
 AGHIC. DFPT. 
 
 
 All rights reserved 
 
CONTENTS 
 
 Introduction ...... 
 
 General Plan of the Experimental Fields 
 
 The Rothamsted Soil ..... 
 
 Agdell Field — Crops grown in Rotation 
 
 Barn Field — Mangolds ..... 
 
 Meteorological Observations .... 
 
 The Park — Grass Land mown for Hay every year 
 Broadbalk Field — Wheat .... 
 
 Hoos Field — Barley ..... 
 
 „ Leguminous Plots 
 
 „ Potato Plots — Residue of Manures 
 
 „ Inoculation of Leguminous Plants 
 
 „ Wheat after Fallow 
 
 Little Hoos Field — Residual Value of Manures . ^. ' 
 
 The Incorporated Society for Extending the Rothamsted 
 ments in Agricultural Science 
 
 EXPERI 
 
 4 
 
 6 
 
 7 
 
 7 
 
 11 
 
 17 
 
 19 
 
 29 
 
 35 
 
 41 
 
 41 
 
 44 
 
 45 
 
 45 
 
 48 
 
 299650 
 
INTRODUCTION 
 
 Mr (afterwards Sir) John Bennet Lawes was the founder of the Roth- 
 amsted Experimental 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 of Rothamsted in 1834. In 
 1843 more systematic field experiments were begun, and the services of 
 Dr (afterwards Sir) J. H. Gilbert were obtained as Director, thus starting 
 the long association which only terminated with the death of Sir John 
 Lawes in 1900, followed by that of Sir Henry Gilbert in 1901. 
 
 For many years the Rothamsted Experimental Station was not con- 
 nected with any external organisation, but was maintained entirely at 
 the cost of Sir John Lawes. In 1889 he constituted a trust for the 
 continuance of the investigations, setting apart for that purpose the 
 laboratory (which had been built by public subscription, and presented 
 to him in 1855), certain areas of land on which the experimental plots 
 were situated, and £100,000. 
 
 By the provisions of the trust-deed, the management is entrusted to 
 a committee nominated by the Royal Society (four persons), the Royal 
 Agricultural Society (two persons), the Chemical and Linnean Societies 
 (one each), and the owner of Rothamsted. 
 
 In 1906 Mr J. F. Mason, M.P., presented the Committee with £1000 
 for the building and equipment of the "James Mason" Bacteriological 
 Laboratory, together with a 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 have also made a grant of £2000 to the endowment. 
 The Society for extending the Rothamsted Experiments, founded in 
 1904, has also collected donations amounting to £3400 and annual 
 subscriptions of over £130. This Society was in 1909 incorporated 
 under the Board of Trade, thus giving it the power to hold money in 
 trust for the purposes of the Rothamsted Experiments. 
 
 During the year 1911 a scheme was published from the Board of 
 Agriculture for the encouragement of agricultural research with funds 
 provided by the Development Commission, and this scheme established or 
 assisted a certain number of institutes for fundamental research, each 
 dealing with one great branch of the subject. The Rothamsted Experi- 
 mental Station is recognised as the Institute for dealing with Soil and 
 
INTRODUCTION 5 
 
 Plant Nutrition problems. In accordance with this scheme a capital 
 grant of £3100 was made, and a maintenance grant of £2500 for the 
 current year, and it is expected that an annual grant of this amount will 
 be made to the Station in future. Certain scholarships have also been 
 instituted to provide the training in research work for men who have 
 already qualified in pure science and are desirous of taking up an 
 agricultural career. The holders of some of these scholarships do their 
 work at Rothamsted. 
 
 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 the 
 Broadbalk wheat field certain rearrangements were made in 1852, in which 
 year also the barley experiments on the Hoos field began. The legumin- 
 ous crops on the 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 grass plots began in 1856, and the rotation experiments 
 in 1848. 
 
 It should be remembered that the object of the Rothamsted experi- 
 ments is to study the soil and the plant, and only indirectly to find 
 the most paying method and manuring ; hence neither the nature nor the 
 quantities of material applied are to be taken as indicating the manures 
 to be used in practice. 
 
 A 2 
 
THE ROTHAMSTED SOIL 
 
 The Rothamsted soil was described by Lawcs in 1847, as follows : — 
 "The soil upon which my experiments were tried consists of rather a 
 heavy loam restin<jj upon chalk, capable of producing good wheat when 
 well maiuired ; not sullicicntly heavy for beans, but too heavy for good 
 turnips or barley. The average produce of wheat in the neighbourhood 
 is said to be less than 22 bushels per acre, wheat being grown once in 
 five years. The rent varies from I'Os. to 26s. per acre, tithe free." 
 
 It is fairly uniform in the different fields, and consists essentially of a 
 heavy loam containing little coarse sand or grit, but a considerable amount 
 of fine sand and silt, and a large body of clay. In consequence, the soil 
 has to be worked with care, becoming very sticky and drying to im- 
 practicable clods if moved \\hen wet. It " runs together " if heavy rain 
 falls after a tilth has been established, and then dries with a hard, 
 unkindly surface, these difficulties being much exaggerated on the plots 
 which have been farmed for a long time without any supply of organic 
 matter in the manures. 
 
 The most notable feature in the Rothamsted soil is the amount of 
 calcium carbonate in the surface layer; analyses of the earliest samples 
 available (1856) show more than 5 per cent, in the surfjice soil of Broad- 
 balk field. The subsoil below the depth of 9 inches contains little or no 
 calcium carbonate, and this fact, together with the varying proportion in 
 the surface soil, indicate that the original soil was almost devoid of 
 calcium carbonate, and that the quantity now found in the surface soil 
 has all been applied artificially. 
 
 AGDELL FIELD 
 
 Crops grown in Rotation. 
 
 The Agdell field, Avhich was put under experiment in the year 1848, 
 differs from the other Rothamsted fields in that it is farmed on a four- 
 course rotation of Swedes, barley, clover (or beans) or fallow, and wheat, 
 instead of growing one crop continuously. It is divided into three main 
 plots, one of which (O) has received no manure, the second (M) mineral 
 manures only, and the third (C) a complete manure, containing the same 
 minerals, but also nitrogen in the form of rape cake and ammonium-salts. 
 The manures are applied to the Swedes only, the other three crops of 
 each course being grown without manure. Each of the three plots is 
 further subdivided : — Half the plots carry clover or beans as the third 
 crop of the course, and half the plots are bare fallow. This shows the 
 effect of introducing the leguminous crop into the rotation, as compared 
 with the bare fallow. 
 
 On this field the long-continued cropping without manure on O affects 
 the successive crops in the rotation very differently. The Swede crop is 
 least capable of growing in the impoverished soil, and is reduced to less 
 than a ton per acre ; the clover and barley crops are also small, but the 
 deep-rooted wheat crop is comparatively little affected, and yielded as 
 much as 24-2 bushels per acre in 1911, the sixty-fourth year without any 
 
A.— Plan of the Plots in Agdell Field on which Experiments have been made on 
 
 Four-Course Rotation. 
 
 1848 and onwards. 
 
 Clover 
 
 F<3lla\Y 
 
 PLOT 2 
 
 PLOT 1 
 
 PLOT 4 
 
 PLOT 3 
 
 PLOT G 
 
 PLOT 5 
 
 rr H 
 
 C. Complete Manure for Root Crops. 
 , As " M," and 
 
 * 200 lb. Ammonium-salts, and 
 2000 lb. Rape Cake 
 per acre. 
 
 M. Minerals only for Root Crops. 
 500 lb. Superphosphate, 
 500 lb. Sulphate of Potash. 
 100 lb. Sulphate of Soda, 
 200 lb. Sulphate of Magnesia, 
 per acre. 
 
 O. 
 
 Unmanured. 
 
 Total area of ploughed land, about 3 acres. Area of each of the 6 divisions, f acre. 
 
 The 2 lower divisions, Unmanured continuously (Plots 5 and 6). 
 
 The 2 middle divisions. Mineral Manure, for the Roots, each Course (Plots 3 and 4). 
 
 The 2 upper divisions. Mineral and Nitrogenous Manure, for the Roots, each Course 
 
 (Plots 1 and 2). 
 The 3 left hand divisions. Clover (or Beans), 3rd year each Course. 
 The 3 right-hand divisions. Fallow, 3rd year each Course. 
 
 The double lines indicate division paths between plot and plot. 
 
CROPS IN ROTATION 9 
 
 manure. With minerals, but without nitrogen, the Swedes continue to 
 ofive a fair crop ; the barley and wheat are better than on the unmanured 
 plot, while the clover grows almost as freely as on the completely 
 manured plot. 
 
 Table I. — Effect of Mamire on Crops grmvn in rotation, Agdell Field. Average 
 produce per acre over the seven last Com'ses, 1884-1911. 
 
 
 o. 
 
 M. 
 
 C. 
 
 Unmanured. 
 5 and 6. 
 
 Mineral 
 Manure. 
 3 and 4. 
 
 Complete 
 Manare. 
 1 and 2. 
 
 Roots (Swedes)" .... Cwt. 
 
 Barley Grain .... Bush. 
 Barley Straw .... Cwt. 
 
 Clover Hay* .... Cwt. 
 Bean Corn t . . . Bush. 
 Bean Straw f . Cwt. 
 
 WTieat Grain .... Bush. 
 Wheat Straw .... Cwt. 
 
 15-0 
 
 14-5 
 10-9 
 
 9-9 
 
 15-8 
 
 8-7 
 
 24-8 
 21-3 
 
 201-4 
 
 19-4 
 12-8 
 
 42-3 
 
 28-2 
 16-9 
 
 34-7 
 32-2 
 
 373-6 
 
 28-0 
 18-6 
 
 39-9 
 19-5 
 11-5 
 
 35-5 
 33-0 
 
 Average of 5 courses. 
 
 t Average of 2 courses. 
 
 Table II. — Cro2}s grown in rotation, Agdell Field. Produce per acre over the 
 last complete Course (\Gth), 1908-1911. 
 
 Year. 
 
 Crop. 
 
 o. 
 
 Unmanured. 
 
 M. 
 
 Mineral 
 Manure. 
 
 C. 
 
 Complete Mineral 
 
 and Nitrogenous 
 
 Manures. 
 
 5. 
 
 Fallow. 
 
 6. 
 
 Beans 
 
 or 
 Clover. 
 
 3. 
 
 Fallow. 
 
 4. 
 
 Beans 
 or 
 
 Clover. 
 
 1. 
 Fallow. 
 
 2. 
 
 Beans 
 
 or 
 Clover. 
 
 1908 
 1909/ 
 1910 
 191l/ 
 
 Roots (Swedes) . Cwt. 
 
 Barley Grain . . Bush. 
 Barley Straw . . Cwt. 
 
 Clover Hay . . Cwt. 
 
 Wheat Grain . . Bush. 
 Wheat Straw . Cwt. 
 
 21-6 
 
 11-4 
 10-1 
 
 23-9 
 20-4 
 
 6-4 
 
 10-0 
 11-3 
 
 17-4 
 
 24-5 
 21-4 
 
 179-0 
 
 17-4 
 12-7 
 
 31-9 
 28-6 
 
 235-8 
 
 22-1 
 16-9 
 
 64-1 
 
 37-8 
 33-5 
 
 395-4 
 
 26-8 
 18-7 
 
 33-3 
 29-3 
 
 314-0 
 
 33-4 
 23-8 
 
 76-7 
 
 38-0 
 32-5 
 
 When the Plots 2 and 4 grow a good crop of clover, the residues of 
 the crop have a very beneficial effect upon the succeeding crops of the 
 rotation, as compared with the crops of Plots 1 and 3, which are bare 
 fallowed; the wheat is increased by something like 15 per cent., the roots 
 (although manured) are slightly better, and the barley, following the 
 roots, still shows the value of the preceding clover crop. No such residue 
 seems to be left behind by the bean crop, whenever that is taken in the 
 rotation instead of clover. On the unmanured Plot 6, only, the clover 
 shows little or no effect on succeeding crops, because there its growth is 
 too small to leave behind any residue of nitrogen. 
 
10 
 
 AGDELL FIELD 
 
 Unr 
 
 lured 
 
 Complete Manure 
 
 Minerals only, 
 no Nitrogen 
 
 Fig. 1. — EflFect of Manure upon Crops grown in Rotation. Total Produce. Average 
 of Five Courses (1884-1903). Swedes in 100 cwt. ; Barley and Wheat in 1000 lb. ; 
 and Clover in 10 cwt. 
 
 Table III. — Crops groivn in rotation, Agdell Field. Effect of the largest Clover or 
 Bean Crop on the following Wheat Crop. Total produce per acre. 
 
 
 Clover, 
 1910. 
 
 Wheat, 1911. 
 
 Beans, 
 
 18(52. 
 
 Wheat, 1863. 
 
 After 
 Fallow. 
 
 After 
 Clover. 
 
 Difference 
 due to 
 Clover. 
 
 After 
 Fallow. 
 
 After 
 Beans. 
 
 Difl'erence 
 due to 
 Beans. 
 
 O. Unmanured 
 
 M. Mineral Manure . 
 
 C. Complete Manure 
 
 Cwt. 
 17-4 
 64-1 
 76-6 
 
 Lb. 
 3876 
 5338 
 
 5454 
 
 Lb. 
 4052 
 6292 
 6163 
 
 Per cent. 
 + 4-5 
 + 17-9 
 + 13-0 
 
 Lb. 
 3603 
 4033 
 5755 
 
 Lb. 
 7222 
 7910 
 8792 
 
 Lb. 
 5281 
 6090 
 7674 
 
 Per ceut. 
 -26-9 
 -23-0 
 -12-7 
 
 Table IV. — Crops grown in 7'otation, Agdell Field. Effect of Clover or Beans on the 
 following Wheat Crops. Total produce per acre. 
 
 
 Clover 
 Crops.* 
 
 Wheat, t 
 
 Bean 
 Crops. J 
 
 Wheat.§ 
 
 After 
 Fallow. 
 
 After 
 Clover. 
 
 Difference 
 due to 
 Clover. 
 
 After 
 Fallow. 
 
 After 
 Beans. 
 
 Difference 
 due to 
 Beans. 
 
 O. Unmanured 
 M. Mineral Manure . 
 C. Complete Manure 
 
 Cwt. 
 14-0 
 47-0 
 50-1 
 
 Lb. 
 4028 
 5147 
 5493 
 
 Lb. 
 8696 
 6052 
 R093 
 
 Per cent. 
 - 8-2 
 + 17-6 
 + 0-9 
 
 Lb. 
 
 1888 
 2615 
 3177 
 
 Lb. 
 4907 
 5528 
 6092 
 
 Lb. 
 4373 
 5447 
 5929 
 
 Per cent. 
 -10-9 
 
 - 1-5 
 
 - 2-7 
 
 * 7 years (1874, 18S2, 1886, 18y4, U»02, lyO(5, and 1910). 
 t 7 years (1875, 18H3, 1887, 1895, 1903, 1907, and 1911). 
 % 8 years (1854, 1858, 1SIJ2, 1-6G, 1870, 1878, 1890, and 1898). 
 § 8 years (1855, 1859, 18U3, 1867, 1871, 1879, 1891, and 1899). 
 
CROPS IN ROTATION 
 
 11 
 
 The cliagrain, Fig. 2, shows in a graphic form the benefit the whole 
 rotation receives from the growtli of clover, even when tlie root crop 
 receives nitroiroiious inaiunx's. 
 
 Wheat 
 
 After Clover. 
 
 After Fallow. 
 
 Fig. 2.— Comparative Effect of Clover or Bare Fallow on the succeeding Crops in the 
 Rotation. Total Produce— In 1000 lb. for Clover, Wheat, and Barley, and in 
 100 cwf. for Roots. 
 
 BARN FIELD 
 
 Mangolds. 
 
 The experiments upon mangolds began in 1876, but the land had been 
 receiving similar manures for other root crops since 1856. 
 
 The field is divided longitudinally into eight strips running the whole 
 length of the field ; each of these .strips receives one manure throughout 
 its length : farmyard manure alone on Strip 1, and in combination with 
 superphosphate and sulphate of potash on Strip 2, nothing on Strip 8, 
 superphosphate alone on Strip 5, superphosphate and sulphate of potash 
 
B. — Plan of the Plots in Barn Field on which Experiments have been made 
 
 with Root Crops. 
 
 1843 and onwards. 
 
 Vail ft/. 
 MangokU, 
 unmanured. 
 
 Total area of ploughed land, about 8 acres. 
 
 n, 2, 5, 6, 7, and 8, of each Series, rather over f acre. 
 I 3, of each Series, about ^V acre. 
 1 4, of each Series, about \ acre. 
 V9, rather over j^ acre. 
 The double hnes indicate division paths between plot and plot. 
 
 Area of Plots 
 
MANGOLDS 
 
 13 
 
 on Strip 6, and complete minerals, including sulphate of magnesia and 
 common salt, on Strip 4. The strips are then subdivided into plots by 
 cross-dressings of nitrogenous manures ; nothing on the O series, nitrate 
 of soda on Series N, ammonium-salts on Series A, rape cake on Series C, 
 and a combination of ammonium-salts and rape cake on Series AC. 
 
 Table V. — Experiments on Mangolds, Barn Field, beginning 1876. 
 Quantities of Manures per acre per annum. 
 
 
 Strip Manures. 
 
 Nitrogenous Manu 
 all the 
 
 res running across 
 Strips. 
 
 
 o 
 
 
 
 
 Series O. 
 
 N. 
 
 A. 
 
 AC. 
 
 C. 
 
 strip. 
 
 t6 
 
 a, 
 o 
 
 & 
 
 s. 
 
 11 
 
 II 
 
 o 
 
 
 
 
 
 
 
 
 6 
 a 
 o 
 
 
 S 
 
 3* 
 
 S 
 
 55 
 
 a n 
 
 E 
 
 (§5 
 
 
 
 
 
 
 
 
 
 < 
 
 
 < 
 
 
 
 Tons. 
 
 Cwt. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 1 
 
 14 
 
 
 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 2 
 
 14 
 
 3-5 
 
 5obt 
 
 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 4 
 
 
 3-5 
 
 500 
 
 200 
 
 200 
 
 
 
 550 
 
 400 
 
 •2000 
 
 400 
 
 2000 
 
 5 
 
 
 3-5 
 
 
 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 6 
 
 
 3 -.5 
 
 500 
 
 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 7: 
 
 
 3-0 
 
 
 200 
 
 200 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 8 
 
 
 
 
 
 
 
 
 550 
 
 400 
 
 2000 
 
 400 
 
 2000 
 
 * Equal parts Sulphate and Muriate Ammonia of commerce, 
 t The addition of Potash to Plot 2 began in 1895. X Commenced in 1903 only. 
 
 Table VI. — Barn Field Mangolds. Produce of Roots and Leaves per acre. 
 
 Season 1912. 
 
 strip. 
 
 strip Manures. 
 
 Cross-Dressings. 
 
 0. 
 
 N. 
 
 A. 
 
 AC. 
 
 C. 
 
 None. 
 
 Nitrate 
 of Soda. 
 
 Ammonium- 
 salts. 
 
 Rape Cake 
 and 
 Ammonium- 
 salts. 
 
 Rape 
 Cake. 
 
 1 
 2 
 
 4 
 
 5 
 6 
 
 7 
 8 
 
 Dung only . . . I 
 Dung, Super., Potash . I 
 
 Complete Minerals . - 
 
 Superphosphate only . 
 
 Super, and Potash . [ 
 
 Super., Sulph. Mag., ( 
 and Chloride Sodium \ 
 
 None . . . . -! 
 
 Tons. 
 R. 16-91 
 L. 4-20 
 
 R. 18-51 
 L, 4-37 
 
 R. 2-62 
 
 L. 1-05 
 
 R. 2-10 
 
 L. 1 -04 
 
 R. 2-13 
 
 L. 0-86 
 
 R. 2 04 
 
 L. 0-97 
 
 R. 114 
 
 L. 0-88 
 
 Tons. 
 
 29-38 
 
 6-79 
 
 29-92 
 
 7-87 
 
 / 15-25 
 V*15-05 
 r 4-33 
 i *5-23 
 
 9-46 
 
 3-48 
 
 12-22 
 
 3-28 
 
 13-03 
 
 3-73 
 
 4-10 
 
 2-70 
 
 Tons. 
 24-51 
 
 7-47 
 
 27-85 
 
 8-42 
 
 I 10-78 
 
 I 2-9i) 
 J 
 
 8-14 
 
 2-54 
 
 10-30 
 
 2-98 
 
 11-12 
 
 3-14 
 
 1-48 
 
 1-52 
 
 Tons. 
 25-76 
 
 9-00 
 
 31-80 
 
 10-35 
 
 27-99 
 
 9-20 
 
 8 -63 
 
 5-17 
 
 24-36 
 
 8-50 
 
 24 00 
 
 8-46 
 
 8-82 
 
 5-20 
 
 Tons. 
 23-75 
 
 7-43 
 
 28-39 
 
 7-67 
 
 21-53 
 
 4-83 
 
 910 
 
 3-78 
 
 19-20 
 
 3-68 
 
 21-27 
 
 4-90 
 
 9-07 
 3-93 
 
 B. = roots. 
 Received an equivalent amount of Phosphoric Acid, 
 
 L. = leaves. 
 Nitrogen, and Potash, but without any Soda Salts. 
 
14 BARN FIELD 
 
 The value of farmyard manure in growing mangolds is evident, 
 especially when they are grown continuously on the same land. In 
 favourable seasons it is possible to obtain good crops by the aid of 
 manures containing no organic matter, as seen in 1912; but in ordinary 
 years the bad texture of the soil which results, and its tendency to lose 
 water on account of the lack of humus, affect both the germination of 
 the seed and the growth of the plant in its early stages. 
 
 Table VII. — Barn Field Mangolds. Average produce of Roots per acre 
 over .34 years (1876 to 1912).* 
 
 strip. 
 
 Strip Manures. 
 
 Cross-Dressings. 
 
 o. 
 
 N. 
 
 A. 
 
 AC. 
 
 C. 
 
 None. 
 
 Nitrate 
 of Soda. 
 
 Ammonium- 
 salts. 
 
 Eape Cake 
 and 
 
 Ammonium- 
 salts. 
 
 Rape 
 Cake. 
 
 1 
 2 
 4 
 5 
 6 
 8 
 
 Dung only . 
 Dung, Super. , Potash f 
 Complete Minerals 
 Superphosphate only . 
 Super, and Potash 
 None .... 
 
 Tons. 
 18-15 
 18-87 
 5-05 
 4-92 
 4-32 
 3-69 
 
 Tons. 
 26-24 
 26-63 
 17-71 
 15-05 
 15-42 
 9-94 
 
 Tons. 
 22-48 
 24-37 
 14-75 
 
 7-04 
 14-08 
 
 5-61 
 
 Tons. 
 24-84 
 27-24 
 26-73 
 
 9-68 
 23-42 
 
 9-29 
 
 Tons. 
 24-69 
 26-40 
 22-11 
 10-78 
 19-28 
 9-71 
 
 1S85, 1901, and 1908 omitted. 
 
 t The addition of Potash to Plot 2 only began in 1895. 
 
 Effect of Nitrogen. 
 
 To ascertain the effects of nitrogen, it is best to examine Strip 4, 
 which receives a complete mineral manure with different compounds of 
 nitrogen. Series A, which receive ammonium-salts, should also be 
 compared with Series N, receiving nitrate of soda. The general superi- 
 ority of nitrate of soda as a nitrogenous manure for mangolds is most 
 strikingly seen on Plots 5, where potash is omitted. 
 
 The diagram. Fig. 3, shows on the left hand the average results 
 obtained with the varying amounts and compounds of nitrogen on the 
 Plots 4 in question, where there is an abundant supply of mineral manure. 
 The right-hand half of the diagram shows the effect of the same nitro- 
 genous manures when used in conjunction with dung instead of complete 
 minerals. 
 
 The injurious effects of the very large amounts of nitrogen added to 
 some of the plots is very manifest wherever there is more nitrogen than 
 the plant can properly deal with. The leaves have a dark green appear- 
 ance, are much curled and crinkled, and show an increased tendency to 
 variegation, the chlorophyll collecting into dark green or almost black 
 blotches on the lighter background of the leaf. The leaf-stalks are often 
 much more coloured, and become a bright orange-yellow. 
 
 On these plots the leaves do not ripen off and obtain the general 
 yellow flaccid appearance presented on the more healthy plots when the 
 crop is ready to lift ; instead, the outer leaves begin to die and shrivel up 
 quite early in October ; in some places they show numbers of dead spots 
 and burnt-looking patches round the edges of the leaf. 
 
MANGOLDS 
 
 15 
 
 Thus, towards the end of OrtohtT, the ph)ts receiving the excess of 
 nitro'^on present a very unhealthy api)eiirance ; a lar<;e proportion of tlie 
 plants seem scorched and withered as regards the outer leaves, and only 
 show a cluster of small dark green active leaves at the heart. 
 
 WITU COMPLETE MINERALS. 
 
 (riots 4.) 
 
 WITH DUNG. 
 (Plots 1.) 
 
 Fig. 3. — Mangolds. Effect of increasing amounts of Nitrogen. Aveiage 
 Produce of Roots per acre, 1876-1902. 
 O = No Nitrogenous Manure. I N = 86 lb. Nitrogen as Nitrate of Soda. 
 
 A = 86 lb. Nitrogen as .\mraonium-salts. | C = 98 lb. Nitrogen as Rape Cake. 
 AC - 98 lb. Nitrogen as Rape Cake, and 86 lb. Nitrogen as Amraonium-salts. 
 
 Effect of Mineral Manures. 
 
 The effect of the different mineral constituents of a manure upon the 
 mangold crop can be seen by an examination of Plots 4, 5, and 6. 
 
 'i'he great increase of crop comes as a rule when potash is added to 
 the superphosphate, and is to be correlated with the fact that the 
 mangold is essentially a sugar-producing plant, and that large supplies of 
 potash seem to be essential to the processes in the plant which result in 
 the formation of sugar and similar carbohydrates. 
 
 The effect of potash and of the other saline manures is plainly visible 
 in the appearance of the plants themselves. On the plots receiving potash 
 the plant begins to ripen early, the leaves turn yellow and become Haccid, 
 so that in October these plots may be seen outlined from the rest by their 
 liffhter tint. 
 
16 
 
 BARN FIELD 
 
 Series 
 
 
 
 With 
 
 No Nitrogenous 
 
 Manure. 
 
 N 
 
 A 
 
 With 
 
 With 
 
 Nitrate 
 
 Ammonium 
 
 of Soda. 
 
 Salts. 
 
 c 
 
 With 
 Rape-cake. 
 
 AC 
 
 With 
 
 Rape-caJ<e A 
 
 Ammonium Salts. 
 
 D 
 
 No Minerals. 
 
 ^Superphosphate. pl]Superphosphate 
 i |v£n and Potash . 
 
 Superphosphate , Pota^ , 
 Magnesia and Soda. 
 
 Fig. 4.— Mangolds. Effect of various Mineral Manures. Average 
 Produce of Roots per acre, 1876-1902. 
 
 Effect of Artificial Manures with Dung. 
 
 A comparison of Strip 2 with Strip 1 shows the 
 superphosphate and sulphate of potash to the dung 
 manures apphed to Strip 1. A heavier crop and a healthier plant 
 obtained, especially where a large amount of nitrogenous manure is used. 
 Since in the earlier experiments it was found that superphosphate had no 
 beneficial effect when used with dung, we can put down the superiority of 
 Strip 2 over Strip 1 to the sulphate of potash which is now used. 
 
 effect of adding 
 and nitrogenous 
 
 IS 
 
 Effect of Manures upon the Texture of the Soil. 
 
 On the strong Rothamsted soil several of the manures employed have 
 an injurious action upon the texture of the soil and often prevent a 
 satisfactory tilth being obtained in the spring, to the great injury of the 
 crop. This is particularly seen where no organic manure is used ; both 
 dung and rape cake tend to keep the land in good condition. Of the 
 artificial manures nitrate of soda and sulphate of potash have the worst 
 effect upon the land, making it very sticky when wet, and hard and caked 
 when dry. Superphosphate on the contrary promotes a friable tilth. 
 
METEOROLOGICAL OBSERVATIONS 
 
 The rainfall has been measured at Ilothamsted since February 1853 in 
 a 5-inch funnel g;au<i;e, and in a rectangular gauge (7 feet 3*12 inches by 
 6 feet), having an area of one-thousandth acre. 
 
 In addition to these gauges, an 8-inch Board of Trade gauge has been 
 euiploved since January 1881. The ground on which the gauges are 
 situated is 420 feet above sea-level. 
 
 The amount of water percolating through bare soil has been measured 
 since 1870 by means of three drain-gauges, each having an area of one- 
 thousandth acre. These were constructed by undermining the soil at the 
 desired deptlis — 20, 40, and 60 inches respectively — and inserting perfor- 
 ated iron plates to support the soil. When this was completed, trenches 
 were cut round the blocks of soil, and these were then isolated by means 
 of brick and cement walls. The external soil was then returned. The 
 percolating water falls on to zinc funnels, from which it passes to the 
 measuring cylinders. 
 
 Barometric and temperature records have been kept since 1873, and 
 since July 1891 daily observations of the bright sunshine have been made 
 by means of a Campbell- Stokes recorder. More recently a self-recording 
 soil thermometer has been set up. 
 
 The average yearly rainfall as measured at Rothamsted during the 
 sixty years, 1853-1912, is 28*34 inches. 
 
 Rain. 
 Inches. 
 
 Sun- 
 shine. 
 
 
 
 
 
 
 
 
 
 
 
 
 nours. 
 
 
 
 
 
 
 / 
 / 
 
 N 
 
 
 
 
 
 200 
 
 
 
 1 
 
 / 
 / 
 / 
 
 / 
 
 
 
 
 \ 
 \ 
 
 \ 
 \ 
 
 
 
 
 150 
 
 
 
 / 
 
 
 
 
 _____ 
 
 
 \ / 
 
 
 
 
 
 / 
 
 / 
 
 
 
 ^ 
 y 
 
 
 X 
 
 \/ 
 
 
 ?9in^ 
 
 TOO 
 
 % 
 
 / 
 
 / 
 
 X' 
 
 
 
 
 
 l>1 
 
 S 
 
 
 V^ 
 
 ■ — -^ 
 
 y/ 
 
 
 
 
 
 '^> 
 
 A-' 
 
 
 
 /'? 
 
 
 / 
 / 
 
 
 
 
 
 "'' 
 
 V-N 
 
 
 'in 
 
 ^4^ 
 
 
 
 ^^ 
 
 
 
 
 
 
 ^\ 
 
 
 
 iK'e^ 
 
 
 \ 
 
 
 
 
 
 
 
 
 % 
 
 Mean 
 
 Temper- 
 ature. 
 
 70° 
 
 60° 
 
 50° 
 
 40° 
 
 Jan. Feb. Mar. Apl. May June July Aug. Sept. Oct. Nov. Dec. 
 
 Fig. 5.— Rainfall : Average of 60 years (1853-1912). 
 
 Sunshine : Average of 20 years (1892, 1893, and 1895-1912). 
 Mean Temperature : Average of 35 years (1878-1912). 
 
18 
 
 METEOROLOGICAL OBSERVATIONS 
 
 Table VIII. — Meteorological Summary. 
 
 
 Rainfall. 
 
 Bright Sunshine. 
 
 Temperature. 
 
 Average, 60 years 
 
 Average, 
 
 20 years 
 
 
 Average, 35 years 
 
 
 (1853-1912). 
 
 (1892 
 
 1893, and 1895-1912). 
 
 (187S-1912). 
 
 Total 
 Fall. 
 
 Rainy 
 
 Days. 
 
 
 Per 
 cent. 
 
 Days with 0-1 
 hour, or more. 
 
 Means. 
 
 ■g .-i 
 
 
 Actual. 
 
 Per 
 
 cent. 
 
 Total. 
 
 Actual. 
 
 Per 
 cent. 
 
 Mini- 
 mum. 
 
 Maxi- 
 mum. 
 
 
 
 Inches. 
 
 No. 
 
 
 Hours. 
 
 
 No. 
 
 
 °F. 
 
 °F. 
 
 °F. 
 
 January . 
 
 2-34 
 
 16 
 
 52 
 
 55-2 
 
 21 
 
 17 
 
 55 
 
 31-7 
 
 42-0 
 
 36-9 
 
 February 
 
 1-81 
 
 14 
 
 48 
 
 71-1 
 
 26 
 
 19 
 
 68 
 
 32-6 
 
 44-1 
 
 38-4 
 
 March . 
 
 1-92 
 
 14 
 
 45 
 
 115-9 
 
 31 
 
 26 
 
 84 
 
 33-7 
 
 48-3 
 
 41-0 
 
 April 
 
 1-84 
 
 13 
 
 43 
 
 170-9 
 
 41 
 
 27 
 
 91 
 
 37-0 
 
 54-2 
 
 45-6 
 
 May 
 
 2-19 
 
 13 
 
 42 
 
 199-6 
 
 42 
 
 29 
 
 93 
 
 42-5 
 
 60-6 
 
 51-6 
 
 June 
 
 2-45 
 
 12 
 
 41 
 
 197-8 
 
 41 
 
 27 
 
 91 
 
 48-4 
 
 66-2 
 
 57-3 
 
 July . 
 
 2-50 
 
 13 
 
 43 
 
 217-9 
 
 45 
 
 30 
 
 96 
 
 51-8 
 
 69-8 
 
 60-8 
 
 August . 
 
 2-69 
 
 14 
 
 45 
 
 198-6 
 
 44 
 
 30 
 
 95 
 
 51-3 
 
 68-5 
 
 59-9 
 
 September 
 
 2-37 
 
 13 
 
 44 
 
 157-3 
 
 42 
 
 27 
 
 92 
 
 47-4 
 
 63-9 
 
 55-7 
 
 October . 
 
 3-18 
 
 18 
 
 57 
 
 104-1 
 
 32 
 
 25 
 
 80 
 
 41-5 
 
 55-3 
 
 48-4 
 
 November 
 
 2-58 
 
 16 
 
 55 
 
 61-1 
 
 23 
 
 19 
 
 62 
 
 36-5 
 
 48-2 
 
 42-4 
 
 December 
 Whole year 
 
 2-47 
 
 17 
 
 54 
 
 42-5 
 
 18 
 
 16 
 
 51 
 
 33-0 
 
 43-5 
 
 38-3 
 
 28-34 
 
 173 
 
 47 
 
 1592-0 
 
 35 
 
 292 
 
 80 
 
 40-6 
 
 55-4 
 
 48-0 
 
 Table IX. — Rainfall and Drainage, etc., at Rothamsted, 1912. 
 
 
 Rain. 
 
 Drainage. 
 
 
 Temperature. 
 
 
 
 Number 
 
 
 
 
 
 
 
 Total FaU. 
 
 of Rainy 
 Days. 
 
 
 
 
 Bright 
 
 
 
 
 
 
 Soil 
 20 ins. 
 deep. 
 
 Soil 
 40 ins. 
 deep. 
 
 Soil 
 60 ins. 
 deep. 
 
 Sunshine. 
 
 Max. 
 
 Min. 
 
 
 5-inch 
 
 TirViyth 
 
 TD Truth 
 
 
 
 Funnel 
 
 Acre 
 
 . ere 
 
 
 
 
 
 
 
 
 Gauge. 
 
 Gauge. 
 
 Gauge. 
 
 
 
 
 
 
 
 
 Inches. 
 
 Inches. 
 
 No. 
 
 Inches. 
 
 Indies. 
 
 Inches. 
 
 Hours. 
 
 °F. 
 
 °F. 
 
 January , 
 
 3-738 
 
 3-886 
 
 18 
 
 3-684 
 
 3-636 
 
 3-582 
 
 41-2 
 
 43-0 
 
 33-4 
 
 February . 
 
 2-008 
 
 2-210 
 
 17 
 
 1 -825 
 
 1-875 
 
 1-854 
 
 39-2 
 
 46-9 
 
 35-4 
 
 March 
 
 4-141 
 
 4-288 
 
 21 
 
 3-423 
 
 3-440 
 
 3-357 
 
 89-4 
 
 51-0 
 
 39-0 
 
 April 
 
 0-131 
 
 0-166 
 
 2 
 
 0-003 
 
 0-035 
 
 0-038 
 
 2:^9-5 
 
 58-4 
 
 36-8 
 
 May . 
 
 1-41.5 
 
 1-474 
 
 12 
 
 0-007 
 
 0-017 
 
 0-034 
 
 177-0 
 
 64-7 
 
 45-2 
 
 June. 
 
 3-139 
 
 3-284 
 
 16 
 
 0-514 
 
 0-547 
 
 0-508 
 
 194 1 
 
 65-8 
 
 49-0 
 
 Julv . 
 
 3-225 
 
 3-354 
 
 14 
 
 1-134 
 
 1-174 
 
 1-079 
 
 151-0 
 
 70"-4 
 
 53-4 
 
 Aufjust 
 
 6-277 
 
 6-528 
 
 27 
 
 4165 
 
 4-112 
 
 4-001 
 
 98-9 
 
 62-4 
 
 49-0 
 
 September 
 
 2 -.528 
 
 2 718 
 
 10 
 
 1-639 
 
 1-523 
 
 1 -;.00 
 
 101-5 
 
 59-4 
 
 44-8 
 
 October . 
 
 2-63i 
 
 2-744 
 
 14 
 
 1 -89.i 
 
 1-866 
 
 1-867 
 
 135-4 
 
 56-1 
 
 36-9 
 
 November 
 
 2-407 
 
 2-517 
 
 14 
 
 1-936 
 
 1-988 
 
 1-961 
 
 39-9 
 
 48-1 
 
 36-5 
 
 December 
 Total or Mean 
 
 3-263 
 
 3-423 
 
 23 
 
 3-109 
 
 3-046 
 
 3041 
 
 30-4 
 
 49-9 
 
 37-9 
 
 34-904 
 
 36-592 
 
 188 
 
 23-334 
 
 23-259 
 
 22-825 
 
 1337-5 
 
 56-3 
 
 41-4 
 
THE PARK 
 
 19 
 
 THE PARK 
 
 Gkass Land Mown for Hay every Year 
 
 Tlie experiments upon grass at Rolhamsted began in 1856, about 7 
 acres of the park close to the house being set aside for the purpose. The 
 land has been in grass as long as any recorded history of it exists, for 
 some centuries at least. It is not known that seed has ever been sown, 
 and at the beginning of the experiments the herbage on all the plots was 
 apparently uniform. 
 
 The plots, of which there are twenty in all, vary somewhat in size, 
 which lies between one-half and one-eighth of an acre. Up to 1874 in- 
 clusive the grass was only cut once, the aftermath being fed off by sheep. 
 Since that time there has been no grazing, and the plots are generally cut 
 twice in the year. The grass is made into hay in the usual way, and the 
 whole produce of each plot is then weighed. 
 
 Table X. 
 
 Manuring of the Permanent Grass Plots per acre per annum, 
 1 856 and since. 
 
 Plot. 
 
 3 
 
 12 
 2 
 
 5-1 
 
 1 
 
 5 
 17 
 
 4-1 
 
 8 
 
 7 
 5-2 
 
 15 
 
 4-2 
 10 
 
 9 
 
 11-1 
 
 11-2 
 
 16 
 14 
 
 Abbreviated Description 
 of Manures. 
 
 j-Unmanured every year . . . . 
 
 Unraanured ; following Dung first 8 years . 
 
 (N. half) Unmanured ; following Am- 
 monium-salts alone for 42 years 
 
 Ammonium-salts alone ; with Dung also 
 first 8 years 
 
 Ammonium-salts alone (to 1897) 
 
 Nitrate of Soda alone 
 
 Superphosphate of Lime .... 
 
 Mineral Manure without Potash 
 
 Complete Mineral Manure .... 
 
 (S. half) Mineral Manure following Am- 
 monium-salts alone for 42 years 
 
 As Plot 7; Ammonium-salts alone first 13 
 years 
 
 As Plot 7 ; Nitrate Soda alone first 1 8 years 
 
 Superphosphate and Ammonium-salts 
 
 Mineral Manure (without Potash) and Am- 
 monium-salts 
 
 Complete Mineral Manure and Ammonium- 
 salts 
 
 Complete Mineral Manure and Ammonium- 
 salts 
 
 As Plot 11-1, and Silicate of Soda 
 
 Complete Mineral Manure and Nitrate Soda 
 Complete Mineral Manure and Nitrate Soda 
 
 Nitrogenous 
 Manures. 
 
 
 Mineral Manures. 
 
 
 a 
 
 .3 . 
 
 11 
 
 S 
 
 So 
 i o 
 
 P. 
 
 
 1 = 
 
 ©42 
 2 a 
 
 O 
 
 S =J 
 ia'o 
 
 Lb. 
 
 Lb. 
 
 Cwt. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 200 
 
 
 
 
 
 
 
 400 
 
 275 
 
 3-5 
 3-5 
 
 
 *250 
 
 100 
 
 
 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 
 
 3-5 
 
 500 
 
 
 
 
 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 400 
 
 
 3-5 
 
 
 
 
 
 400 
 
 
 3-5 
 
 
 *250 
 
 100 
 
 
 400 
 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 600 
 
 
 3-5 
 
 600 
 
 100 
 
 100 
 
 
 600 
 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 400 
 
 
 275 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 
 550 
 
 3-5 
 
 500 
 
 100 
 
 100 
 
 
 Reduced in 1905 to 100 lb. 
 
C. — Plan of the Plots in the Park on which Experiments have been made on the 
 Mixed Herbage of Permanent Grass Land. 
 
 1856 and onwards. 
 
 ]8 
 
 
 10 
 
 5-2 
 
 n 
 
 /5 
 
 //'X 
 
 //-/ 
 
 10 
 
 8 
 
 5-1/ 
 
 U-2 
 
 A-l 
 
 3 
 
 fk 
 
 IS 
 
 iL 
 
 n 
 
 Area of Plots 
 
 Total area under Experiment, about 7 acres. 
 
 ri, 2, 3, 4-1, 4-2, 5-1, 5-2, 11-1, 11-2, and 12, each I acre. 
 I 6, 7. 8, 9, 10, 13, and 18, each \ acre. 
 \ 14, 15, 16, and 17, each \ acre. 
 119 and 20, each | acre. 
 
GRASS FOR HAY 
 
 21 
 
 Table XI. — Produce of J/aj/ per aor. Average over the period of 57 years (1856- 
 1912), the 10 years (1903-1912), and. the individual year 1912. Rothamsted. 
 Total of Jirst and second crops (if any). 
 
 Plot. 
 
 3 
 
 12 
 2 
 
 5-1 
 
 5 
 17 
 
 4-1 
 
 8 
 
 7 
 5-2 
 
 6 
 
 15 
 
 4-2 
 10 
 
 9 
 
 11-1 
 
 11-2 
 
 16 
 
 14 
 
 Abbreviated Description 
 of Manures. 
 
 lUnraatuired every year 
 
 I 
 Unmanured ; following Farmyard Dung for first 
 
 8 years 
 
 (N. half) Unmanured ; following Ammonium-salts 
 
 alone for 42 years ...... 
 
 Ammonium-salts alone ( = 43 lb. N.); with Farm- 
 yard Dung for first 8 years .... 
 Ammonium-salts alone = 86 lb. Nitrogen (to 1897) 
 Nitrate of Soda alone = 43 lb. Nitrogen 
 
 Superphosphate of Lime ..... 
 Mineral Manure without Potash .... 
 Complete Mineral Manure ..... 
 (S. half) Complete Mineral Manure; following 
 
 Ammonium-salts alone for 42 years . 
 Complete Mineral Manure as Plot 7; followiug 
 
 Ammonium-salts alone first 13 years . 
 Complete Mineral Manure as Plot 7 ; following 
 
 Nitrate of Soda alone first 18 years . 
 
 Superphosphate and Atnmonium-salts = 86 lb. N. . 
 
 Mineral Manure (without Potash^), and Ammo- 
 nium-salts =86 lb. N 
 
 Complete Mineral Manure and Ammonium-salts 
 -:86 lb. N 
 
 Complete Mineral Manure and Ammonium-salts 
 = 129 lb. N 
 
 As Plot 11-1, and Silicate of Soda. 
 
 Complete Mineral Manure and Nitrate Soda 
 = 43 lb. N 
 
 Complete Mineral Manure and Nitrate Soda 
 = 86lb. N 
 
 Averages over 
 
 Season 
 1912. 
 
 57 years 
 (18&6-1912). 
 
 10 years 
 (1908-1912). 
 
 Cwt. 
 20-9 
 23-9 
 
 Cwt. 
 16-2 
 21-0 
 
 Cwt. 
 10-2 
 20-1 
 
 28-6* 
 
 20-2 
 
 15-4 
 
 14 •411 
 
 15-0 
 
 7-1 
 
 35 -91 
 (26-1)** 
 33-711 
 
 26-8 
 33'-2 
 
 23-6 
 31-2 
 
 21 -611 
 
 28-0 
 
 40-9 
 
 21-0 
 
 27-4 
 50-9 
 
 17-2 
 22-5 
 46-4 
 
 23-2tt 
 
 21-9 
 
 15-8 
 
 37-2+ 
 
 45-3 
 
 37-8 
 
 36 -8§ 
 
 45-8 
 
 37-0 
 
 33-511 
 
 34-5 
 
 25-1 
 
 47-7 
 
 40-5 
 
 32-5 
 
 54-3 
 
 54-7 
 
 36-0 
 
 66-5 
 73-3 
 
 71-2 
 79-3 
 
 67-2 
 72-6 
 
 46-311 
 
 48-1 
 
 40-7 
 
 56-9«| 
 
 57-7 
 
 52-9 
 
 * After the change. 
 
 t 
 
 t 
 
 ' Including Potash first 6 years. 
 
 Before the change, 42-9 cwt. || 54 years only (1859-1912). 
 
 ,, 495 cwt. i 56 years only (1858-1912). 
 
 „ S0-6cwt. *♦ 42 years (1856-1897). 
 
 ,, 35-4 cwt. ft 15 years (1898-1912). 
 
 The Unmanured Plots. 
 Two of the plots have remained without manure during the whole of 
 the experiment. They are situated near the extremities of the field, and 
 show a slight but constant difference in crop. Taking the average of the 
 whole period, these unmanured plots have produced rather more than a 
 ton of hay per acre per annum. If we compare the successive ten-year 
 returns, there is no sign of approaching exhaustion or great falling-off' in 
 crop from year to year. The impoverishment of these unmanured plots is 
 more to be seen in the character of the herbage than in the gross weio-ht 
 of produce. Weeds of all descriptions occupy the land, and the relative 
 proportion they bear to the grasses and clovers has increased from year to 
 
 B 2 
 
22 
 
 THE PARK 
 
 year. A fair proportion of clovers, both red and white, is found on these 
 plots, but the weeds, which amount to 28 per cent, taking the average 
 
 Table XII. — Percentages of Gramineous, Leguminous^ and Miscellaneous Herbage. 
 Average of determinations inade at different times during bl years (1856-1912, 
 and 1902 separately). Rothamsted. First crops. 
 
 
 
 Averages of dnterminations 
 
 
 
 
 
 
 over 57 years 
 
 Season 1902 
 
 
 
 
 
 1856 1912) 
 
 
 
 
 
 Plot. 
 
 Manures. 
 
 
 
 
 
 
 
 Gram- 
 
 Legu- 
 
 Miscel- 
 
 Gram- 
 
 Legu- 
 
 Miscel- 
 
 
 
 inese. 
 
 minosae. 
 
 laneie. 
 
 inese. 
 
 niinosse. 
 
 laneae. 
 
 
 Per cent. 
 
 Per cent. 
 
 Per cent. 
 
 Per cent. 
 
 Per cent. 
 
 Per cent. 
 
 3 
 12 
 
 j-Unraanured every year \ 
 
 61-0 
 
 64-8 
 
 8-7 
 9-0 
 
 30-3 
 26-2 
 
 34-3 
 
 38-1 
 
 7-5 
 16-1 
 
 58-2 
 45-8 
 
 2 
 
 Unraanured; following Farm- 
 
 
 
 
 
 
 
 
 yard Dung tor first 8 years . 
 
 75-5 
 
 4-3 
 
 20-2 
 
 24-4 
 
 5-7 
 
 69-9 
 
 5-1 
 
 (N. half) Unraanured follow- 
 ing Ammonium-salts alone 
 
 
 
 
 
 
 
 
 42 years .... 
 
 
 
 
 76-9 
 
 0-6 
 
 22-5 
 
 1 
 
 Ammonium-salts alone ( — 43 
 lb N.); with Farmyard 
 
 
 
 
 
 
 
 
 Dung for first 8 years . 
 
 87-7 
 
 0-7 
 
 11-6 
 
 77-6 
 
 1-4 
 
 21-0 
 
 5 
 
 Ammonium-salts alone = 86 lb. 
 
 
 
 
 
 
 
 
 N. (to 1897) .... 
 
 (80-5) 
 
 (0-4) 
 
 (19-1) 
 
 
 
 
 17 
 
 Nitrate of Soda alone = 43 lb. 
 
 
 
 
 
 
 
 
 N 
 
 68-8 
 
 1-5 
 
 29-7 
 
 43-8 
 
 3-4 
 
 52-9 
 
 4-1 
 
 Superphosphate of Lime 
 
 59-3 
 
 7-4 
 
 33-3 
 
 54-4 
 
 15-4 
 
 30-2 
 
 8 
 
 Mineral Manure without Pot- 
 
 
 
 
 
 
 
 
 ash 
 
 61-0 
 
 9-2 
 
 29-8 
 
 28-8 
 
 22-1 
 
 49-1 
 
 " 7 
 
 Complete Mineral Manure . 
 
 58-8 
 
 24-9 
 
 16-3 
 
 20-3 
 
 55-3 
 
 24-4 
 
 5-2 
 
 (S. half) Complete Mineral 
 Manure followmg Ammo- 
 
 
 
 
 
 
 
 
 nium-salts alone for 42 years 
 
 
 ... 
 
 
 68-7 
 
 0-8 
 
 30-5 
 
 6 
 
 Complete Mineral Manure as 
 Plot 7 ; following Ammo- 
 
 
 
 
 
 
 
 
 nium-salts alone first Vi yrs. 
 
 64-8 
 
 18-6 
 
 16-6 
 
 18-4 
 
 61-0 
 
 20-6 
 
 15 
 
 Complete Mineral Manure as 
 Plot 7 ; following Nitrate of 
 
 
 
 
 
 
 
 
 Soda alone first 18 years 
 
 59-5 
 
 22-6 
 
 17-9 
 
 26-2 
 
 63-1 
 
 10-7 
 
 4-2 
 
 Superphosphate and Ammo- 
 
 
 
 
 
 
 
 
 nium-salts =86 lb. N. . 
 
 89-1 
 
 0-1 
 
 10-8 
 
 91-5 
 
 (0-01) 
 
 8-5 
 
 10 
 
 Mineral Manure (without Pot- 
 ash*) and Ammonium-salts 
 
 
 
 
 
 
 
 
 = 86 lb. N 
 
 90-7 
 
 0-1 
 
 9-2 
 
 97-6 
 
 (0-01) 
 
 2-4 
 
 9 
 
 Complete Mineral Manure and 
 
 
 
 
 
 
 
 
 Ammonium-salts = 86 lb. N. 
 
 89-9 
 
 0-3 
 
 9-8 
 
 91-2 
 
 1-3 
 
 7-5 
 
 11-1 
 
 Complete Mineral Manure and 
 
 
 
 
 
 
 
 
 Ammonium-salts = 129 lb. N. 
 
 96-5 
 
 
 
 3-5 
 
 99-2 
 
 
 
 0-8 
 
 11-2 
 
 As Plot 11-1, and Silicate of 
 
 
 
 
 
 
 
 
 Soda 
 
 97-4 
 
 
 
 2-6 
 
 99-5 
 
 
 
 0-5 
 
 16 
 
 Complete Mineral Manure 
 
 
 
 
 
 
 
 
 and Nitrate Soda = 43 lb. N. 
 
 82-9 
 
 5-4 
 
 11-7 
 
 61-7 
 
 12-8 
 
 25-5 
 
 14 
 
 Coniplete Mineral Manure 
 
 
 
 
 
 
 
 
 and Nitrate Soda = 86 lb. N. 
 
 89-0 
 
 3-1 
 
 7-9 
 
 88-8 
 
 3-7 
 
 7-5 
 
 Including Potash first 6 years. 
 
 over the whole period, have of late years constituted nearly one-half of 
 the herbage. The most prominent species among the grasses are the 
 
GRASS FOR HAY 
 
 23 
 
 Quaking Grass, so generally taken as a sign of poor land, which con- 
 stituted 20 per cent, of the whole herbage in 1903, and Sheep's I'escue ; 
 among leguminous plants the Bird's-foot Trefoil ; and Burnet, Hawkbit, 
 and Black Knapweed among the weeds. 
 
 Use of Nitrogenous Manures alone. 
 
 : \ Three of the plots — 17, 5, and 1 — show the effect of the long-con- 
 tinued use of nitrogenous without any mineral manures. Plot 5 for forty- 
 two years received 86 lb. of nitrogen as ammonium-salts, Plot 17 half 
 the quantity of nitrogen in the shape of nitrate of soda, and Plot 1 the 
 same half quantity of nitrogen as ammonium-salts, though on this plot 
 dung was applied in each of the first eight years of the experiment. The 
 
 Without Nitrogen 
 -A. 
 
 With Nitrogen. 
 
 Plots 3&I2 
 
 Fig. 6. — EflFect of the various Ash constituents with and without Nitrogen on the 
 produce of Hay per acre. Average over 47 years (1856-1902). 
 
 Plots 3 and 12. Unmanured. | Plot 4-2. Super, and Arara.-salts =86 lb. N. 
 
 Plot 4-1. Superphosphate. I Plot 10. Minerals (without Potash) and 
 
 Plot 8. Minerals with Potash. | Amm.-salts = 86 lb. N 
 
 Plot 7. Complete Mineral Manure. I Plot 9. Complete Mineral Manure and 
 
 Amm.-salts-86 lb. N. 
 
24 THE PARK 
 
 treatment of Plot 5 is now altered, but during the years the ammonium- 
 salts were applied the average yields per acre from these plots were : — 
 
 Plot 17, single nitrate (18 years, 1858-1875), 33-9 * cwt. 
 „ 15, double „ (18 „ 1858-1875), 35-4 cwt. 
 
 Plot 1, single ammonia (34 years, 1864-1897), 37*7 f cwt. 
 „ 5, double „ (34 „ 1864-1897),. 24-4+ cwt. 
 
 It is very evident when a nitrogenous manure is used alone for grass, 
 nitrate of soda is far more effective than the ammonium salts ; e.g., on 
 l*lot 17 it has given an average crop of 34 cwt. against 26 cwt. produced 
 by double the quantity of nitrogen in ammonium-salts on Plot 5. 
 
 Mineral Manures used alone. 
 
 On three of the plots no nitrogenous manures have been applied since 
 the beginning of the experiments. On Plot 7 a complete mineral manure, 
 supplying phosphoric acid, potash, magnesia, and soda, is used ; Plot 8 
 has received the same application, but without potash, since 1861, while 
 Plot 4-1 receives superphosphate only. With the complete minerals 
 a fair crop is grown, avei'aging over 1^ ton of hay for the first cut alone. 
 The reason that the crop on this plot is maintained, although no nitrogen 
 is supplied in the manure, lies in the free growth of leguminous plants. 
 It will be seen that, taking the average over the whole period, the 
 leguminous plants form 25 per cent, of the herbage, and the proportion 
 has increased from year to year. 
 
 The omission of potash on Plot 8 has caused a very striking difference 
 both in the crop and in the character of the herbage. The average crop 
 has been about one-third less over the whole period, and shows a pro- 
 gressive decline in fertility, until at the present time it is little more than 
 half that of Plot 7. The poor results on this plot, as compared with 
 Plot 7, must be put down to its poverty in leguminous herbage, the 
 development of which seems to depend on a free supply of potash. Of 
 late years the proportion of leguminous plants on this plot has amounted 
 to about one-half of that found on Plot 7, the grasses are also less, the 
 difference being made up by an increased amount of weed. 
 
 Plot 4-1, which each year has received superphosphate only, now pre- 
 sents a very impoverished appearance, and is giving little more crop than 
 the unmanured plots. Indeed, the aspect of this plot, where the most 
 abundant grass is Quaking Grass, and where weeds, chiefly Hawkbit, 
 Burnet, and Plantain, are unusually prominent, would seem to indicate 
 that the land is more exhausted here than on the unmanured plot. 
 
 Complete Manures — Nitrogen and Minerals. 
 
 Among the plots which receive both nitrogenous and mineral manures,^ 
 Plot 9, with a complete mineral manure and ammonium-salts should be 
 compared with Plot 14, which is exactly similar except that the nitrogen 
 is applied in the form of nitrate of soda, and again with Plot 16, where 
 
 * Over the whole period of 55 yrs. (1858-1912) Plot 17 gave an average of 33-7 cwt. per acre. 
 + „ ,, „ of 49 „ (1864-1912) „ 1 „ „ 33-6 „ 
 
 % „ „ ,. of 42 „ (1856-1897) „ 5 „ „ 26-1 
 
GRASS FOR HAY 
 
 25 
 
 Cwt. per Acre 
 60 
 
 Plots 3&I2 
 
 Fig. 7.— Effect of Nitrogenous Manures on the produce of Hay per acre. Average 
 over 47 years (1856-1902). 
 
 Plot 3 and 12, Unmanured. 
 
 Plot 7. Complete Mineral Manure, no Nitrogen. 
 Plot 9. Do. and Amm. -salts = 86 lb. N. 
 
 Plot 11. Do. do. =129 lb. N. 
 
 Plot 16. Do. and Nitrate of Soda = 43 lb. N. 
 
 Plot 14. Do. do. =86lb. N. 
 
 only' half the amount of nitrogen is applied, but again as nitrate of soda. 
 The. nitrate of soda gives the heavier yield, the herbage is also more 
 
26 
 
 THE PARK 
 
 diversified, and there is not the total absence of leguminous plants which 
 marks the plots receiving ammonium-salts. Two characteristic plants, 
 Soft Brome Grass and Beaked Parsley, are found only on the plots 
 receiving nitrate of soda, the corresponding umbelliferous plant where 
 ammonium-salts are used being the Earth Nut (Conopodium). 
 
 On Plot 11 the same mineral manures are applied with an extra 
 amount of ammonium-salts, so that the nitrogenous manuring is excessive. 
 As a result the vegetation consists entirely of tufts of three coarse grasses 
 — Meadow Foxtail, Yorkshire Fog, and Tall Oat Grass. The soil has 
 also become sour and unhealthy, with the result that the plant is dying in 
 patches, except on the upper portion of the plot where lime has been 
 applied, and on the half numbered 11-2 where the silicate of soda is 
 used. 
 
 The effect of omitting potash from the complete manure is seen on 
 Plot 10, and again on Plot 4-2, where superphosphate and ammonium- 
 salts only are applied. It is noticeable that the grass on these plots is 
 weak in the straw and liable to fungoid attacks. 
 
 Effect of Lime. 
 
 In November 1883 each plot was divided longitudinally, and upon 
 the western half of each 2000 lb. per acre of fresh burnt lime (slacked) 
 was applied, and in November 1887 the eastern half of most of the 
 plots also received 2000 lb. per acre. Plot 5, however, received none, 
 and the western portion of Plots 11-1 and 11-2, which had received the 
 lime in 1883, in 1887 received 2000 lb. per acre more, while the eastern 
 
 ROTHAMSTED PARK HAY— FIRST CROP 
 Table XIII. — Pi-oduce per acre on the urdivied aivd limed jyortions of the plots. 
 
 Plot. 
 
 Unlimed. 
 
 Limed. 
 (Lime applied January 1903.) 
 
 1903. 
 
 1904. 
 
 1905. 
 
 1906. 
 
 Average. 
 
 1903. 
 
 1904. 
 
 1905. 
 
 1906. 
 
 Average. 
 
 2 
 
 3 
 4-2 
 
 7 
 
 8 
 
 9 
 10 
 11-1 
 11-2 
 13 
 16 
 
 Cwt. 
 
 13-35 
 
 10-61 
 
 3.'5-29 
 
 49-46 
 
 23-17 
 
 .^0-07 
 
 37 -5 .T 
 
 70-20 
 
 79-46 
 
 56-46 
 
 48-68 
 
 Cwt. 
 26-91 
 :i2-46 
 43-19 
 61-87 
 39 -.^9 
 63-69 
 44-02 
 85-42 
 87-90 
 64-67 
 53-34 
 
 Cwt. 
 
 20-21 
 
 15-79 
 
 24-72 
 
 44-34 
 
 25-08 
 
 36-87 
 
 30-04 
 
 24-71 
 
 50-16 
 
 22-38 
 
 46-19 
 
 Cwt. 
 
 15-43 
 
 12-18 
 
 23-41 
 
 34-38 
 
 21-12 
 
 39-01 
 
 28-92 
 
 42-89 
 
 61-68 
 
 17-69 
 
 39-25 
 
 Cwt. 
 18-98 
 15-26 
 31-65 
 47-51 
 27-24 
 47-41 
 35-13 
 55-81 
 69-80 
 40-30 
 46-87 
 
 Cwt. 
 20-28 
 16-34 
 43-77 
 51-91 
 21-63 
 60-49 
 45-00 
 80-84 
 77-87 
 60-43 
 45-68 
 
 Cwt. 
 
 37-12 
 
 30-20 
 
 47-84 
 
 61-83 
 
 35-45 
 
 69-76 
 
 48-86 
 
 88-40 
 
 81-64 
 
 70-60 
 
 52-12 
 
 Cwt. 
 22-89 
 18-78 
 3a -08 
 47-15 
 25-71 
 52-18 
 38-40 
 50-97 
 56-30 
 25-76 
 41-97 
 
 Cwt. 
 15-94 
 11-88 
 27-62 
 41-40 
 19-74 
 49-95 
 32-52 
 51-62 
 65-46 
 17-18 
 38-47 
 
 Cwt. 
 24-06 
 19-30 
 38-08 
 50-57 
 25-63 
 58-10 
 41-20 
 67-96 
 70-32 
 43-49 
 44-56 
 
 half, which received none in 1HS3, then (1887) received 4000 lb. per acre. 
 In December 1896, the eastern half of Plot 5 which had not pre\nously 
 received any lime, received 4000 lb. per acre of freshly burnt lime 
 
GRASS FOR HAY 
 
 27 
 
 (slacked); and the western half, which had in 1883 received 2000 lb., 
 received another 2000 lb. per acre. 
 
 In Januarv 1903 the plots were divided transversely, and a 
 dressing of 2* 00 lb. per acre of (juicklime (ground) was applied to 
 the south half of Plots 1 to 4-2, 7 to 11-2, 13 and 10, and this dressing 
 was repeated in January 1907. 
 
 The results of the 1903 dressing are given in Tables XIII. and XIV., 
 and show that distinct improvement is effected on the unmanured plot 
 and those receiving sulphate of ammonia, viz.. Plots 2, 3, 4-2, 9, 10, and 
 11-1. The effect of the liming had largely worn off in the fourth year 
 after the application, excepting on Plots 9 and 11-1. 
 
 ROTHAMSTED PARK HAY 
 
 Table XIV. — Effects of Livie and the ordinary Manures. Afean of 3 years, 1904-6 
 (first crops). Produce and Botanical Composition of the Uerhaye. 
 
 Plot. 
 
 Manures. 
 
 Produce, 
 
 Botanical Composition. 
 
 per acre. 
 
 Graminese. 
 
 Leguminosae. 
 
 other Orders. 
 
 Unlimed. 
 
 Limed. 
 
 Unlimed. 
 
 Limed. 
 
 Unlimed. 
 
 Limed. 
 
 Unlimed. Limed. 
 
 7 
 8 
 
 Complete Mineral 
 
 Manure . 
 Mineral Manure 
 
 without Potash 
 
 Cwt. 
 
 Per cent. 
 
 Per cent. 
 
 Per cent. 
 
 46-9 
 28-6 
 
 50-1 
 27-0 
 
 53-3 
 39-9 
 
 42-0 
 
 45-8 
 
 20-8 
 11-7 
 
 34-4 
 18-6 
 
 25-9 
 
 48-4 
 
 23-6 
 35-6 
 
 Changes in the Herbage following changes in Manuring. 
 
 Plot 6 was up to 1868 manured with ammonium-salts alone, like the 
 adjoining Plot 5; the ammonium-salts were then replaced by a complete 
 mineral manure containing potash. The result is seen in the way 
 leguminous plants have gradually invaded the plot until they now 
 predominate, as they do on Plot 7, where mineral manures have been 
 used throughout. The southern half of Plot 5 has also been manured 
 with minerals instead of ammonium-salts since 1898, and the gradual 
 invasion of leguminous plants may now be seen in progress. The northern 
 half of Plot 5 has been unmanured since 1898, when the ammonium-salts 
 were discontinued, and the invasion of the leguminosae is much slower. 
 
 On Plot 15 nitrate of soda was applied up to 1875, when a change to 
 a complete mineral manure was made, with the same result of the incoming 
 of the leguminous plants. 
 
 Plot 18, which up to 1005 was in an impoverished condition, has 
 since been receiving a complete manure except that phosphates are 
 omitted. 
 
J).— Plan of the Plots in Broadbalk Field on tvhich Wheat has been grown 
 
 since 1843-4. 
 
 20 
 
 u 
 
 'f 
 
 IS 
 
 18 
 
 n 
 
 n 
 
 1(0 
 
 iL 
 
 fS 
 
 If 
 
 fu 
 
 /^ 
 
 13 
 
 li 
 
 12 
 
 n 
 
 II 
 
 II 
 
 10 
 
 10 
 
 9 
 
 4-3 
 
 ^-i 
 
 BA 
 
 m 
 
 Brick Trench for collecting the Pipe Drainage from each Plot. 
 
 Total area of ploughed land about 11 acres. 
 Area of Plots 3-4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, and 19, each J acre. 
 Area of Lands A and B of Plot 2, each fV acre. 
 Area of Plot 20, about \ acre. 
 
 The double lines indicate division paths between plot and plot ; also a path across 
 the centre of each plot. 
 
WHEAT 29 
 
 Use of Dung. 
 
 Three plots were selected in 1905 to illustrate the effects of dun<r 
 applied occasionally, either alone or in combination with artificial 
 manures. The quantities applied per acre are as follows : — 
 
 Plot 19. 14 tons Dung 1905, and every fourth year. 
 Unmanured intervening years. 
 
 Plot 20. 14 tons Dung 1905, and every fourth year. 
 
 n cwt. Nitrate of Soda ^ ^ intervenino- 
 
 200 lb. Superphosphate - ^'^'''^> intervening 
 
 100 lb. Sulphate of Potash ) ^^^^ ' 
 
 Plot 13.* 14 tons Dung 1905, and every fourth year. 
 
 6 cwt. Fish Guano 1907, and every fourth year.f 
 
 BROADBALK FIELD 
 
 Wheat 
 
 The experiments on the continuous growth of wheat were begun in 
 the Broadbalk field in 1843, but for the first eight years the manuring was 
 of a varied description, so that only three of the plots have received the 
 same treatment during the whole period of seventy years. The plots as 
 seen to-day began in 1852, since which time the few changes in manuring 
 have been matters of detail and not of principle. 
 
 The chief difficulty experienced in growing wheat continuously is 
 that of keeping the land clean ; not only does the crop occupy the 
 ground for the greater part of the year, and so leave little opportunity 
 for cleaning operations, but the weeds whose habit of growth is favoured 
 by the crop tend to accumulate from year to year. Thus in spite of 
 repeated hand-hoeings, some weeds, like the "Black Bent" grass, 
 Alopectiriis agrestls, are kept under with the greatest difficulty. 
 
 On Plot 3 wheat has been grown without manure every year since 
 1843, for four years previously no manure had been applied to the field, 
 so that the present crop is the seventy-fourth without manure. After a 
 drop in production during the first few years, the yield has been 
 practically constant for the last fifty years, fluctuating only with the 
 season, and showing no immediate prospect of declining. The average 
 crop over this period has amounted to about 12i bushels per acre, 
 approximately equal to the average yield, taking the whole world over. 
 
 Effect of Nitrogenous Manures. 
 
 Plots 6, 7, and 8 should be compared with Plot 5, since all receive the 
 same mineral manures, but different amounts of nitrogen as ammonium - 
 salts. 
 
 Plot 5, which receives the minerals but no nitrogen, grows very little 
 more than the continuously unmanured plot ; its average over the whole 
 period is only 14-5 bushels, as against 12-6 without manure of any descrip- 
 
 * The southern half of Plot 13 received a dressing of 2000 lb. of ground lime in 1907. 
 t The fish guano was applied in 1910 instead of 1911. 
 
30 
 
 BROADBALK FIELD 
 
 Table 'K^ .—Experiments on Wheat, Broadhalk Field. Manuring of the 
 Plots per acre per annum, 1 852 and since. 
 
 Plot. 
 
 Abbreviated Description 
 of Manuring. 
 
 Nitrogenous Manures. 
 
 Mineral Manures. 
 
 •a . 
 
 1 
 o 
 
 to 
 
 o 
 
 I" 
 
 6 
 (la 
 
 ft 
 
 o 
 
 cuo 
 'Jl 
 
 o 
 
 IE . 
 
 !-§ 
 
 m 
 
 
 2 
 
 3 
 
 5 
 
 6 
 
 7 
 
 8 
 
 9 
 
 10 
 
 11 
 
 12 
 
 13 
 
 14 
 
 15 
 
 16 
 17 
 18 
 19 
 
 Farmyard Manure .... 
 
 Unmanured 
 
 Minerals 
 
 Single Araraoniura-salts and Minerals 
 Double do. do. 
 Treble do. do. 
 Single Nitrate and Minerals 
 Double Ammonium-salts alone . 
 
 Do. and Superphosphate . 
 
 Do. do. and Sulph. Soda . 
 
 Do. do. and Sulph. Potash 
 
 Do. do. and Sulph. Mag. . 
 Double Amm.-salts in autumn, and 
 
 Minerals 
 
 Double Nitrate and Minerals 
 \ Minerals alone, or Double Amm.-salts/ 
 / alone, in alternate years . . \ 
 Rape Cake alone .... 
 
 Tons. 
 14 
 
 Lb. 
 
 1889 
 
 Lb. 
 
 275 
 
 550 
 
 Lb. 
 
 200 
 400 
 600 
 
 400 
 400 
 400 
 400 
 400 
 
 400 
 400 
 
 Cwt. 
 
 3 '-5 
 
 3-5 
 
 3-5. 
 
 3-5 
 
 3-5 
 
 3-5 
 3-5 
 3-5 
 3-5 
 
 3-5 
 3-5 
 3-5 
 
 Lb. 
 
 200 
 200 
 200 
 200 
 200 
 
 200 
 
 200 
 200 
 200 
 
 Lb. 
 
 100 
 100 
 100 
 100 
 100 
 
 366-5 
 
 100 
 100 
 100 
 
 Lb. 
 
 ioo 
 
 100 
 100 
 100 
 100 
 
 280 
 
 100 
 100 
 100 
 
 Table XVI. — Experiments on Wheat, Broadhalk Field. Produce of Grain and 
 Htraw per acre. Average over 61 years (1852-1912); and over 10 years (1903- 
 1912) ; also Produce in 1911. 
 
 
 
 Dressed Grain. 
 
 Straw. 
 
 Plot. 
 
 Abbreviated Description 
 
 
 
 
 
 2^ 
 
 
 of Manuring. 
 
 ^ Oi 
 
 jj ca 
 
 S 
 
 ss 
 
 ^ o> 
 
 Ol 
 
 
 
 ipS 
 
 .Sri 
 
 rt 
 
 
 45« 
 
 fl 
 
 
 
 
 
 
 
 
 
 
 
 
 %^' 
 
 c4 
 
 
 Pr,0> 
 
 
 
 
 
 
 
 
 
 
 
 
 > 
 
 ^ 
 
 -Jl 
 
 
 ^ 
 
 M 
 
 
 
 < 
 
 > 
 
 
 <1 
 
 > 
 
 
 
 
 Bush. 
 
 Bush. 
 
 Bush. 
 
 Cwt. 
 
 Cwt. 
 
 Cwt. 
 
 2 
 
 Farmyard Manure 
 
 35-2 
 
 32-8 
 
 35-2 
 
 34-8 
 
 38-2 
 
 36-9 
 
 3 
 
 Unmanured ...... 
 
 
 12-6 
 
 10-0 
 
 12-5 
 
 10-3 
 
 9-3 
 
 9-8 
 
 5 
 
 Minerals 
 
 
 14-5 
 
 12-5 
 
 14-8 
 
 12-1 
 
 11-9 
 
 12-8 
 
 6 
 
 Single Ammonium-salts and Minerals 
 
 
 23-2 
 
 19-0 
 
 17-2 
 
 21-4 
 
 20-7 
 
 17-9 
 
 7 
 
 Double do. do. 
 
 
 32-1 
 
 27-9 
 
 25-6 
 
 32-9 
 
 32-3 
 
 27-6 
 
 8 
 
 Treble do. do. 
 
 
 3rt-6 
 
 33-8 
 
 36-4 
 
 41-1 
 
 42-1 
 
 35-7 
 
 9 
 
 Single Nitrate and Minerals 
 
 
 
 26-0 
 
 29-9 
 
 
 28-7 
 
 29-0 
 
 10 
 
 Double Ammonium-salts alone . 
 
 
 20-0 
 
 16-3 
 
 22-8 
 
 18-4 
 
 16-7 
 
 17-2 
 
 11 
 
 Do. and Superphosphate . 
 
 
 22-9 
 
 17-1 
 
 20-1 
 
 22-3 
 
 20-2 
 
 15-2 
 
 12 
 
 Do. do. and Sulph. Soda 
 
 29-1 
 
 24-6 
 
 27-0 
 
 28-0 
 
 26-2 
 
 20-6 
 
 13 
 
 Do, do. and Sulph. Potash . 
 
 31 
 
 28-7 
 
 29-7 
 
 31-5 
 
 33-1 
 
 27-4 
 
 14 
 
 Do. do. and Sulph. Mag. 
 
 28-8 
 
 22-0 
 
 24-1 
 
 28-0 
 
 24-1 
 
 18-9 
 
 15 
 
 Double Amm.-salts in autumn, and Mmerals 
 
 29-9 
 
 26-4 
 
 24-1 
 
 29-7 
 
 29-0 
 
 22-3 
 
 16 
 
 Double Nitrate and Minerals .... 
 
 
 30-2 
 
 40-4 
 
 
 39-1 
 
 42-4 
 
 17 
 
 1 Minerals alone, or Double Ammonium-salts/* 
 / alone, in alternate years . . . . \t 
 
 14-9 
 
 12-9 
 
 13-8 
 
 13-0 
 
 12-4 
 
 11-7 
 
 18 
 
 29-9 
 
 27-6 
 
 27-3 
 
 29-5 
 
 29-7 
 
 24-6 
 
 19 
 
 Rape Cake alone + 
 
 25-4 22-8 28-6 1 
 
 25-7 
 
 24-8 
 
 24-7 
 
 by Minerals. t Produce by Ammonium-salts. } 20 years (1893-1912). 
 
WHEAT 
 
 31 
 
 Total Produce 
 perAcre 
 
 7000 lb.— 
 
 35: 4. 
 
 irain per Mere 
 
 ,1b. 
 
 Straw per Acre, lb 
 
 Fig. 8.— Broadbalk Wheat. Effect of increasing amounts of Nitrogen on the production 
 of Wheat (Grain and Straw). Average, 51 years (1 852-1902). 
 
 The figures in the labels indicate bushels of Grain and cwt. of Straw. 
 
32 
 
 BROADBALK FIELD 
 
 tion. The yield of the other three plots increases with each addition of 
 nitrogen; the grain increases from 23 bushels with 43 lb. of nitrogen, 
 to 82 bushels with 86 lb. of nitrogen, and to 36^ bushels with 129 lb. of 
 
 Total Produce 
 per Acre 
 
 6000 lb.— 
 
 Straw per Acre, lb. IxnnxsJ Gram per Acre, lb 
 
 Fio. 9. — Comparison of Nitrate of Soda and Ammonium-salts on Wheat. 
 
 Ten years (1893-1902). All Plots receive Minerals alike. 
 
 The figures in the labels indicate bushels of Grain and cwt. of Straw. 
 
 nitrogen ; the straw is even more affected by a free supply of nitrogen, 
 risino- from 21i cwt. to 33 and 41 cwt. as the nitrogen is doubled and 
 trebled. 
 
 Comparative Effect of Nitrate of Soda and Ammonium-salts. 
 Plot 6 should be compared with Plot 9, and Plot 7 with Plot 16. 
 Plots 9 and 16 receive nitrate of soda and mineral manures, so that 
 
WHEAT 
 
 33 
 
 riot 9 has the same manuring as Plot 6, and Plot 16 as Plot 7, except 
 that the ammonium-salts on Plots 6 and 7 are replaced by ocjuivalent 
 amounts of nitrogen as nitrate of soda. The manuring of Plots 9 and 
 16 has, however, been changed during the progress of tlie experiments, 
 so that they are only comparable with 6 and 7 since 1885. Taking a 
 recent ten year average, as set out in the diagram. Fig. 9, it will be seen that 
 nitrate of soda is a more effective source of nitrogen than the ammonium- 
 
 Total Produce 
 perAcr« 
 
 6000 lb. ^— ' ■ 
 
 SGIb.N. 
 
 after Minerals only 
 
 in PreviousYear. 
 
 Straw per Acre ,1b. 
 
 Grain per Acre, lb , 
 
 Fig. 10.— Comparative Effects on Wheat of Ammonium-salts applied at different times. 
 Averages— Plots 5, 17, and 18, 51 years (1852-1902). 
 Plots 7 and 15, 25 years only (1878-1902). 
 The figures in the labels indicate bushels of Grain and cwt. of Straw. 
 
 C 
 
34 BROADBALK FIELD 
 
 salts; the single application yields 16 per cent, more grain and 26 per 
 cent, more straw than the corresponding amount of ammoniuni-salts ; the 
 double application, however, yields practically the same amount of 
 grain, and only about 1 cwt. more straw. 
 
 Effect of the Mineral Ccnstituents. 
 
 The series of Plots 7, 10, 11, 12, 13, and 14 all receive the same 
 amount of nitrogen — 86 lb., in the form of 400 lb. of ammonium-salts per 
 acre — but differ in regard to their mineral manuring. Plot 10 receives 
 nothing beyond the nitrogen. Plot 11 has superphosphate also, while 12, 
 13, and 14 receive a further addition of sulphate of soda, sulphate of 
 potash, or sulphate of magnesia respectively, all three of which are 
 combined to form a complete mineral manure on Plot 7. 
 
 Retention of Manures by the Soil. 
 
 As a rule 100 lb. of the ammonium-salts are applied in the autumn 
 when the seed is sown, the rest being reserved for a top-dressing in the 
 spring. On one of the plots, however. Plot 15, the whole 400 lb. of 
 ammonium-salts is applied in the autumn, otherwise the manuring is 
 identical with that of Plot 7. The crop, however, on Plot 15 is on the 
 average below that of Plot 7, showing that some loss takes place when 
 the ammonium-salts are applied before the plant is able to utilise them. 
 Plots 17 and 18 further illustrate the fate of ammonium-salts. These 
 plots receive the dressing of Plot 7 — 400 lb. ammonium-salts and com- 
 plete minerals — but the ammonium-salts and the minerals are applied in 
 alternate years to the two plots. Thus in 1912 Plot 17 receives ammo- 
 nium-salts but no minerals, and Plot 18 the minerals without the 
 ammonium-salts, and the treatment is reversed in 1911 and again in 1913, 
 The plot which in any year is receiving minerals without nitrogen derives 
 little or no benefit from the ammonia it had the year before. The crop 
 shows every sign of nitrogen starvation, and amounts on the average to 
 only 14*9 bushels of grain, as compared with 14*5 bushels on Plot 5 which 
 has received minerals without any nitrogen every year since 1852. On 
 the Rothamsted soil, then, we may conclude that the effect of sulphate of 
 ammonia applied to a cereal crop is confined to the season of its applica- 
 tion. In the seasons when the ammonium-salts are applied the crop is but 
 little short of that on Plot 7, and sometimes (as in 191 1) is even greater 
 where minerals are used every year with the same amount of ammonium- 
 salts, thus showing that the previous mineral manuring is carried forward 
 and has an effect in seasons beyond the year of its application. 
 
BARLEY 
 
 35 
 
 HOOS FIELD 
 
 Barley 
 
 The experiments on the continuous growth of barley were begun in 
 the Hoos field in 1852. The arrangement of the plots and the manures 
 applied to each plot have practically been unchanged since, so that the 
 plots to-day show the effects of more than sixty years'" continuous growth 
 of barley under the same treatment year after year. There are four 
 longitudinal strips receiving different combinations of the mineral 
 manures ; these are all crossed by four breadths receiving different nitro- 
 
 Table XVII. — Exj)ei-iments on Barley, IIoos Field. Manuring of the Plots 
 per acre j)er annum, 1852 and since. 
 
 Plot. 
 
 Abbreviated Description 
 
 Nitrogenous Manures. 
 
 Mineral Manures. 
 
 "2 • 
 
 
 i 
 
 o 
 
 £ 
 
 »ja 
 
 <o . 
 
 .2 
 
 
 
 of Manures. 
 
 si 
 
 5 
 
 1 
 
 '5 " 
 
 is 
 
 a 
 
 "1 
 
 5 «! 
 
 0.0. 
 O CO 
 !» O 
 
 -J 
 "5.0 
 
 1-5 
 
 •5 o 
 
 0.32 
 
 So 
 
 o 
 
 -2 a 
 
 CQ*o 
 
 
 
 Tons. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Cwt. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 Lb. 
 
 10 
 
 No Minerals and no Nitrogen 
 
 
 
 
 
 
 
 
 
 
 20 
 
 Superphosphate only, do. 
 
 
 
 
 
 3-5 
 
 
 
 
 
 30 
 
 Alkali Salts only, do. 
 
 
 
 
 
 
 200 
 
 100 
 
 100 
 
 
 40 
 
 Complete Minerals, do. 
 
 
 
 
 
 3-5 
 
 200 
 
 100 
 
 100 
 
 
 1 A 
 
 Ammonium-salts alone . 
 
 
 
 200 
 
 
 
 
 
 
 
 2A 
 
 Superphosphate and Ammo- 
 nium-salts .... 
 
 
 
 200 
 
 
 3-5 
 
 
 
 
 
 3A 
 
 Alkali Salts and Ammonium- 
 salts 
 
 
 
 200 
 
 
 
 200 
 
 100 
 
 100 
 
 
 4A 
 
 Complete Minerals and Ammo- 
 
 
 
 
 
 
 
 
 
 
 
 nium-salts .... 
 
 
 
 200 
 
 
 3-5 
 
 200 
 
 100 
 
 100 
 
 
 1 AA 
 
 Nitrate of Soda alone . 
 
 
 
 
 275 
 
 
 
 
 
 
 2AA 
 
 Superphosphate and Nitrate 
 of Soda . . . . 
 
 
 
 
 275 
 
 3-5 
 
 
 
 
 
 3AA 
 
 Alkah Salts and Nitrate of 
 Soda 
 
 
 
 
 275 
 
 
 200 
 
 100 
 
 100 
 
 
 4AA 
 
 Complete Minerals and Nitrate 
 
 
 
 
 
 
 
 
 
 
 
 of Soda .... 
 
 
 
 
 275 
 
 3-5 
 
 200 
 
 100 
 
 100 
 
 
 1 AAS 
 
 As lAA and Silicate of Soda . 
 
 
 
 
 275 
 
 
 
 
 
 400 
 
 2AAS 
 
 As 2AA and do. 
 
 
 
 ... 
 
 275 
 
 3-5 
 
 
 
 
 400 
 
 3 AAS 
 
 As 3AA and do. 
 
 
 
 
 275 
 
 
 200 
 
 100 
 
 ioo 
 
 400 
 
 4 AAS 
 
 As 4AA and do. 
 
 
 
 
 275 
 
 3-5 
 
 200 
 
 100 
 
 100 
 
 400 
 
 IC 
 
 Rape Cake alone . 
 
 
 1000 
 
 
 
 
 
 
 
 
 2C 
 
 Superphosphate and Rape 
 
 
 1000 
 
 
 
 3-5 
 
 
 
 
 
 3C 
 
 Alkali Salts and Rape Cake . 
 
 
 1000 
 
 
 
 
 200 
 
 100 
 
 ioo 
 
 
 4C 
 
 Complete Minerals and Rape 
 
 
 
 
 
 
 
 
 
 
 
 Cake 
 
 
 1000 
 
 
 
 3-5 
 
 200 
 
 100 
 
 100 
 
 
 7-1 
 
 Unmanured (after dung 20 
 years, 1852-1871) 
 
 
 
 
 
 
 
 
 
 
 7-2 
 
 Farmyard Manure . 
 
 14 
 
 ... 
 
 
 
 
 
 
 
E. — Plan of the Plots in Hoos Field on tvhirh Barley has been Grown 
 
 since 1852. 
 
 
 r 
 
 
 
 
 
 
 / 
 
 SA- 
 
 S(9 
 
 ax 
 
 \X 
 
 / 
 
 
 
 
 ' 
 
 / 
 
 4 
 
 3 
 
 a 
 
 / 
 
 1 
 
 
 
 
 ■ 
 
 1 
 
 A 
 
 5 
 
 5 
 
 / 
 
 
 
 
 
 
 
 G 
 
 auqe Series 
 
 A 
 
 6 
 
 :2 
 
 / 
 
 
 
 
 
 
 
 
 
 \ 
 
 \ 
 
 7-2 
 
 L'l 
 
 4 
 
 3 
 
 5 
 
 / 
 
 
 
 
 
 
 
 "■ 
 
 
 T' 
 
 1>'I 
 
 4 
 
 S 
 
 a 
 
 / 
 
 \ 
 
 cq 
 
 02 
 
 k 
 
 Area of Plots 
 
 Total area of ploughed land, about 5^ acres. 
 
 '1, 2, 3, and 4, of Series O, Series A, and Series C, each xi acre. 
 
 1, 2, 3, and 4, of Series AA and AAS, each y\ acre. 
 
 1 N, 2 N, 5 O, and 5 A, each ^ acre. 
 
 6-1 and 6-2, each about f acre. 
 ^7-1 and 7-2, each about \ acre. 
 
 The double lines indicate division paths between plot and plot. 
 
BARLEY 
 
 37 
 
 genous manures. The mineral manuring on the strips is as follows: — 
 (1) None ; (2) Phosphoric acid only, no potash or alkali salts ; (3) Potash, 
 magnesia, and soda, no phosphoric acid ; and (4) Complete mineral 
 manure, supplying both phosphoric acid and the alkaline salts. Each of 
 
 these is combined with the four cross-dressings of nitrogenous manures 
 
 Series O, no nitrogen ; Series A, ammonium-salts ; Series AA, nitrate of 
 soda ; Series AAS as Series AA and silicate of soda in addition ; and 
 Series C, rape cake. There are other plots, one of which received farm- 
 yard manure for the first twenty years, but has since been unmanured. 
 
 Table XYIU.—Exjyeriments on Barley, Hoos Field. Produce of Grain and Straiv 
 per acre. Averages over 60 years (1852-1911), aTuZ over 10 (1902-1911). Also 
 Produce in 1911 . 
 
 Plot 
 
 Abbreviated Description 
 of Manures. 
 
 Dressed Grain. 
 
 Straw. 
 
 
 §2 
 
 2S 
 
 o> 
 
 O •-! 
 
 OS 
 
 2S 
 
 o» 
 
 
 
 < 
 
 ri 
 
 o 
 
 > 
 
 22 
 
 > 
 
 a 
 o 
 
 1 
 20 
 30 
 40 
 
 No Minerals and no Nitrogen . 
 Superphosphate only, do. 
 Alkali Salts only, do. . . . 
 Complete Minerals, do. 
 
 Bush. 
 
 12-7 
 19-7 
 15-2 
 19-7 
 
 Bush. 
 9-3 
 17-6 
 10-1 
 15-9 
 
 Bush. 
 4-9 
 
 11-9 
 4-3 
 5-9 
 
 Cwt. 
 
 8-4 
 10-0 
 
 8-8 
 11-1 
 
 Cwt. 
 6-2 
 9-2 
 8-2 
 
 12-4 
 
 Cwt. 
 5-5 
 9-1 
 5-3 
 
 7-8 
 
 1 A 
 2A 
 3A 
 
 4 A 
 
 Ammonium-salts alone .... 
 Superphosphate and Ammonium-salts 
 Alkali Salts and do. 
 Complete Minerals and do. 
 
 25-5 
 38-2 
 28-0 
 41-5 
 
 19-7 
 29-7 
 20-3 
 38-4 
 
 13-8 
 10-3 
 
 11-8 
 28-5 
 
 14-7 
 22-0 
 16-9 
 25-0 
 
 13-0 
 19-3 
 15-6 
 25-3 
 
 12-5 
 11-6 
 14-1 
 22-9 
 
 1 AA 
 
 2 AA 
 
 3 AA 
 
 4 AA 
 
 Nitrate of Soda alone .... 
 Superphosphate and Nitrate of Soda 
 Alkali Salts and do. 
 Complete Minerals and do. 
 
 29-3 
 43-1 
 30-0 
 42-7 
 
 23-0 
 38-6 
 21-4 
 37-8 
 
 16-2 
 26-1 
 12-.') 
 28-9 
 
 17-8 
 26-3 
 19-3 
 27-3 
 
 16-1 
 26-5 
 16-1 
 26-3 
 
 17-8 
 24-7 
 14-5 
 23-7 
 
 1 AAS 
 
 2 AAS 
 
 3 AAS 
 
 4 AAS 
 
 As Plot 1 AA and Silicate of Soda . 
 As Plot 2 AA do. do. 
 As Plot 3 AA do. do. 
 As Plot 4 AA do. do. 
 
 32-8* 
 42-3* 
 35-2* 
 43-6* 
 
 28-0 
 37-2 
 29-0 
 40-4 
 
 19-7 
 26-0 
 17-6 
 27-5 
 
 19-7* 
 26-0* 
 21-7* 
 
 27-7* 
 
 18-5 
 25-9 
 20-3 
 27-1 
 
 18-4 
 24-6 
 18-1 
 24-8 
 
 IC 
 2C 
 3C 
 4C 
 
 Rape Cake alone 
 
 Superphosphate and Rape Cake 
 Alkali Salts and do. 
 Complete Minerals and do. 
 
 38-3 
 40-5 
 36-9 
 40-5 
 
 33-4 
 35-4 
 33-1 
 
 38-2 
 
 27-4 
 28-2 
 21-6 
 25-7 
 
 22-1 
 2.i-6 
 22-3 
 24-5 
 
 20-7 
 22-0 
 21-9 
 24-4 
 
 20-7 
 20-8 
 18-6 
 20-1 
 
 7-1 
 
 7-2 
 
 Unmanured (after dung 20 years, 1852-71) 
 Farmyard Manure 
 
 24 -81 
 47-1 
 
 18-3 
 44-3 
 
 9-5 
 23-0 
 
 14-8t 
 29-6 
 
 12-9 
 31-7 
 
 10-5 
 24-0 
 
 * 48 years (1864-1911). 
 
 t 40 years (1872-1911). 
 
 Effect of Nitrogenous Manures. 
 
 The effect of nitrogenous manures upon the barley crop is best seen by 
 
 various Plots 4, all of which receive the same 
 
 comparing the yields of the 
 mineral manures ; the diagram 
 graphic form. 
 
 Fig. 
 
 11, shows this 
 
 same 
 comparison in a 
 
 C 2 
 
38 
 
 HOOS FIELD 
 
 J^ffect of Mineral Manures. 
 
 The diagram, Fig. 12, shows in a graphic form the effects of the 
 various mineral manures, the nitrogen supply being the same in all cases. 
 
 The great importance of phosphoric acid to the barley crop is seen on 
 comparing Plots 3 and 4, which only differ from one another in the 
 omission of phosphoric acid on Plot 3. In the field the most striking 
 
 Total Produce 
 per Acre. 
 
 6000 Ib.- 
 
 Plot 10 
 
 Unmanured 
 
 40. 
 
 Minerals 
 only. 
 
 4 A. 
 
 Minerals 
 
 +43 Ib.N. 
 
 as Ammonia. 
 
 ^ 
 
 Grain per Acre, lb. 
 
 4C. 7-2 
 
 Minerals Farmyard 
 
 +49lb. N. Manure 
 as Raoe Cake. 
 
 Straw per Acre, lb 
 
 Fig. 11. — Yield in Barley (Grain and StrawJ with different sources of Nitrogen. 
 Averages for 51 years (1852-1902). 
 
 The figures in the labels indicate bushels of Grain and cwt. of Straw. 
 
 effect is seen in the hastened maturity brought about by the phosphoric 
 acid. By comparing Plot 2 with Plot 4 we can see the effect of omitting 
 potash from the manure. Where nitrate of soda is used as the source of 
 nitrogen the soda liberates sufficient potash from the soil to supply the 
 needs of the crop, but with ammonium-salts the omission of potash has 
 latterly begun to tell upon the yield, though it did not do so in the 
 earlier years of the experiment. 
 
BARLEY 
 
 39 
 
 Total Produce 
 per Acre. 
 
 > lb. 
 sooo 
 
 4^000 
 
 5000 
 
 Nitrogen 
 
 Nitrogen 
 
 only. 
 
 and 
 
 
 Phosphoric 
 
 
 Acid. 
 
 Nitrogen 
 
 and 
 
 Potash. 
 
 Nitrogen, 
 Phosphoric Acid 
 and 
 Potash. 
 
 Grain per Acre ,lh 
 
 Straw per Acre, lb. 
 
 Fig. 12. — Effect of Mineral Manures on the yield of Barley (Grain and Straw). 
 Mean of Series A, AA, and C. 51 years (1852-1902). 
 
 The figures in the labels indicate bushels of Grain and cwt. of Straw. 
 
40 
 
 HOOS FIELD 
 
 F. — Hoos Field Leguminous Plots. Season 1906. 
 
 < 
 
 I 
 
 o 
 Co 
 
 ats in 
 
 O 
 o 
 
 03 
 
 I 
 
 o 
 
 CO 
 
 Cfc: 
 
 /504 — ->; 
 
 Co 
 o 
 
 C 
 
 o 
 
 O 
 
 CD 
 
 o 
 
 
 CO 
 
 05 
 
 o 
 
 '^^ 
 c:i 
 
 QJ 
 
 o 
 o 
 
 i 
 
 I 
 
 >E 
 
 )0 
 
 )C 
 
 }B 
 
 >A 
 
 [Total area under experiment, about 3 acres.] 
 
 These crops were left for a time, then cereals were introduced, as shown 
 
 in Table XIX., p. 41. 
 
HOOS FIELD 
 
 41 
 
 HOOS FIELD— LEGUMINOUS PLOTS 
 
 1848-9 ONWARDS 
 
 The small plots (see Plan on page 40) represent portions of the 
 original plots on which attempts have been made to grow leguminous 
 plants continuously since 1848. Various combinations of mineral manures 
 have been used up till 1898, but after the first few years very small crops 
 have been grown, and the clovers in particular generally fail. After 
 fallowing in 1903 to clean the plots, they were resown as before in 
 1904. 
 
 The remainder of the area was formerly occupied by similar small 
 plots of the same leguminous plants. These were ploughed up in 1898, 
 and five crops of wheat were taken without manure in order to test the 
 amount of nitrogen accumulated by the leguminous crop and left in the 
 soil. 
 
 In 1904 black tartarian oats were sown, and in the oats, lucerne, red 
 clover, and alsike clover were sown on three strips ; a fourth strip, fallowed 
 in 1904, was sown with vetches in October of that year, as shown in the 
 Plan on page 40. The new plots run across the old ones at right angles. 
 The following table shows the crop obtained in 1905 and each year since 
 to 1912 inclusive. 
 
 
 Table XIX. — Produce, Hoos Field Leguminov^ Land. 
 
 
 
 
 Season 
 1905. 
 
 Season 
 1906. 
 
 Season 
 1907. 
 
 Season 
 1908. 
 
 Season 
 1909. 
 
 Season 
 1910. 
 
 Season 
 1911. 
 
 Season 
 1912. 
 
 Lucerne . 
 Red Clover 
 Alsike Clover . 
 
 Vetches . 
 
 Cwt. 
 38-1 
 
 47-2] 
 
 36-9/ 
 
 45-8 
 
 Cwt. 
 55-2 
 
 Cwt. 
 90-6 
 
 (67-5 
 
 |27-8 
 
 24-2 
 
 Cwt. 
 83-9 
 
 12-2 
 
 Cwt. 
 15-3 
 
 2-4 
 
 4-0 
 
 19-6 
 
 Cwt. 
 53-3 
 
 60-4 
 
 46-3 
 
 Cwt. 
 56-9 
 
 23-0 
 
 35-7 
 
 8-9 
 
 Oats 
 Bush. 
 
 50-9 
 37-2 
 29-1 
 
 Straw 
 Cwt. 
 
 29-5 
 23-5 
 19-2 
 
 Barley 
 bush. 
 36-2 
 
 Straw 
 cwt. 
 25-6 
 
 22-3 
 
 cwt. 
 5-6 
 
 Dates of sowing leguminoui seeds ; — 
 Lucerne . 13th May 1904, and 1st June 1909. 
 
 Red Clover . 13th May 1904, 10th May 1906, and Ist June 1909. 
 Alsike Clover . 13th May 1904, 10th May 1906, and 1st June 1909. 
 
 Vetches . 3rd October 1904, 5tb April 1906, 11th March 1907, 30th May 1907, 5th November 1907, 9bh 
 
 October 1908. Fallow 1910, 18th October 1910. 
 
 HOOS FIELD— POTATO PLOTS 
 
 Residue of Manures 
 
 On ten plots potatoes were grown with various manures for 26 years 
 (1876-1901). In 1902 the manuring was discontinued and barley sown. 
 Table XX. shows the yields obtained. 
 
G. — Plan of the Plots in Hoos Field on which Potatoes tvere grown without 
 Manure, and ivith various Manures. 
 
 26 years, 1876-19C1, 
 
 In 1902 and 1903 Barley, and in 1904 Oats, were sown, without manure, to determine 
 the duration of the residues of the previous manuring. In 1905 and each year to 1911 
 Barley was sown, and in 1912 Oats, on Plots 1-4 without manure. Plots 5-10 sown with 
 Leguminous seeds each year to 1911, and Oats in 1912. 
 
 
 ■ 
 
 ■ 
 
 
 
 
 
 10 
 
 A 
 
 
 k 
 
 ^ 
 
 B 
 S 
 
 I. 
 
 — 
 
 C 
 D 
 
 — 
 
 9 
 
 E 
 F 
 
 7 
 
 G 
 
 s 
 
 6 
 
 / 
 
 Total area of ploughed land, about 2tV acres. Area of each plot, | acre. 
 The double lines indicate division paths between plot and plot. 
 
5 r-l 
 
 O CL 
 
 2- 
 
 §1" 
 
 il 
 
 
 
 •aiwO 
 
 pesS9JQ 
 
 
 ■uiwo 
 passsjQ 
 
 
 UIBJO 
 
 possajQ 
 
 XI CO 
 
 J .-I 
 
 30 
 
 
 3 i 
 
 
 •U!«J9 
 
 pssseiQ 
 
 
 pQssaiQ 
 
 r-« t^ 
 
 ^ 00 
 3 «0 
 
 
 passMQ 
 
 
 •UIBJQ 
 
 passajd 
 
 l«lox 
 
 pess3JQ 
 
 
 X • 
 
 3 OJ 
 
 passajQ 
 
 I^iox 
 
 passajQ 
 
 •.ttWJg 
 
 IB^ox 
 
 3 0> 
 
 passaiQ 
 
 •10M 
 
 a CO 
 
 G2 
 
 
 O rl ,-1 
 
 O Ot 
 
 52 
 
 52 
 
 3 o. 
 
 5 a 
 
 «- 
 
 ■ki " CD OJ to OJ 
 
 (^ g f 1 i) i -^ 
 <-> ^ CO >o o o 
 
 p ip o oo 
 
 53 C<l O <^5 ---I l2 <^ ' 
 
 t>. to «0 «D «D : 
 
 C.99 
 
 B * CO 
 
 1. 19 
 
 e -o <j "^ 
 
 »< Oi oj OS Tj< i^ "^ ' 
 _ 00 c<i Jo cq _ ITS 
 O 00 00 t^ t~ o j^ 
 
 0-69 
 
 e» ja 
 
 
 •2 So ° 
 
 eo 
 
 Tr .-1 
 
 03 t; 
 
 as .g 
 a s 
 
 o ^ 
 
 I i 
 
 
 ^ 3 
 
 o o 
 
 -a 
 o • 
 
 c 
 «^ 
 
 cSi 
 
 iSx! u 
 
 da = 
 and 
 nure 
 
 
 S^^^g 
 
 ' rj 
 
 O ™ 
 
 ^^r- 
 
 ^c^ 
 
 •S^13 
 
 
 o c S 
 
 42 o u 
 
 
 Nitra 
 Nitr 
 Min 
 
 .^r! 
 
44 
 
 HOOS FIELD 
 
 HOOS FIELD 
 
 Inoculation of Leguminous Plants 
 
 Since the land on which potatoes had been formerly grown (see Plan 
 on page 42) is known to have carried no leguminous crop for the last 
 fifty years, it was decided to use those plots which no longer showed 
 much residue of the manures previously applied, i.e., Plots 5-10, for testing 
 the comparative effects of different media for inoculating leguminous 
 plants with their appropriate bacteria. In 1905, therefore. Plots 6, 8, 
 and 10 were divided transversely into four plots ; on A, soil inoculated 
 with Hiltner's preparation from Munich ; on B, soil inoculated with 
 Moore's preparation from the United States ; on C, soil from a field which 
 had carried red clover in 1904, were sown on 7th April; D being left 
 uninoculated. Red clover seed was sown on 15th May over the whole 
 area, and was continued each year to 1911 inclusive; in 1912 a crop of 
 oats was taken. See yield in Table XX. 
 
 Plots 5, 7, and 9 were similarly divided into three plots and sown with 
 cow peas ( Vigna catjang), a leguminous plant quite new to this land. On 
 
 E, the seed was inoculated with Moore's medium just before sowing; on 
 
 F, soil obtained from an old cow pea field in the United States was 
 spread; and G was not inoculated. The cow peas were sown on 16th 
 May, but failed to give a satisfactory plant, and were ploughed up. The 
 plots were sown with red clover in 1906, as part of a further trial of 
 the continuous growth of clover. This continued to 1911 inclusive; in 
 1912 oats were grown on the plots. For results, see Table XX. 
 
 Table XXI. — Experiments on Wheat, alternated with Falloiv, tvithout Manure 
 {Hoos Field), 62 years (1851-1912) ; and grown continuously ivithout Manure 
 {Broadbalk Field), 62 years (1851-1912). 
 Average produce of Grain per acre, and Produce last two years, 1911 and 1912. 
 
 
 Dressed Grain. 
 
 Wheat after Fallow 
 
 each year 
 
 (Hogs Field). 
 
 Wheat after Wheat 
 
 each year 
 
 (Broad balk). 
 
 After Fallow 
 
 + or - 
 after Wheat. 
 
 Averages— Produce after Fallow, reckoned at the yield per Acre 
 of the half in Crop each year. 
 
 5 years (1851-55) . 
 
 10 „ (1856-65) . 
 10 „ (1866-75) . 
 10 „ (1876-85) . 
 10 ,, (1886-95) . 
 10 „ (1896-1905) 
 
 50 „ (1856-1905) 
 57 „ (1851-1912) 
 
 1911 
 
 1912 
 
 Bushels. 
 19-2 
 
 26-1 
 13-5 
 14-8 
 15-1 
 14-3 
 
 16-7 
 
 16-0 
 
 17-0 
 
 4-2 
 
 Bushels. 
 
 14-7 
 
 15-9 
 11-9 
 11-3 
 12-1 
 11-7 
 
 12-5 
 
 12-2 
 
 12-5 
 
 4-5 
 
 Bushels. 
 + 4-5 
 
 + 10-2 
 -t- 1-6 
 + 3-5 
 + 3-0 
 
 + 2-6 
 
 + 4-2 
 + 3-8 
 + 4-5 
 - 0-3 
 
WHEAT AFl^ER FALLOW 
 
 45 
 
 HOOS FIELD 
 
 Wheat after Fallow 
 
 The two half-acre plots in Hoos field are never manured, but every 
 year one carries a wheat crop and the other is given a bare summer fallow, 
 the treatment alternating, so that every year one plot is carrying a wheat 
 crop following a bare fallow. 13y comparing the results obtained with the 
 yield of the unmanured plot growing wheat continuously, the benefit of 
 the bare fallow can be estimated. (See Table XXL) 
 
 LITTLE HOOS FIELD 
 
 Residual Value of Manures 
 
 The object of the experiments in this field is to test the residual value 
 of certain typical manures, i.e., the value of the residues left in the soil 
 after one or more crops have been grown since the time of their applica- 
 tion. To eliminate the effect of season, the result yielded by the residue 
 is in all cases compared with that of a new application of the same 
 manure, as w^ell as with a continuously unmanured check plot. 
 
 The ordinary dung is made by feeding beasts with hay and roots only, 
 the beasts making the cake-fed dung alongside receive also an ordinary 
 allowance of linseed and cotton cake. The two lots of dung are then laid 
 up in heaps for a short time, and weighed out immediately before 
 applying. 
 
 Table XXII. — General Dressings of Mineral Manure on Series A to E, and of 
 Nitrogenous Dressings on Series F to H. 
 
 (Quantities per acre.) 
 
 
 Series A to B. 
 
 
 Series F, G, H. 
 
 1904 
 
 3 cwt. Superphosphate. 
 
 1904 
 
 1 cwt. Sulphate Ammonia. 
 
 1905 
 
 
 1905 
 
 1 cwt. Sulphate Ammonia. 
 
 1906 
 
 3 cwt. Sulphate Potash. 
 
 1906 
 
 2 cwt. Sulphate Ammonia. 
 
 3 cwt. Sulphate Potash. 
 
 1907 
 
 3 cwt. Superphosphate. 
 
 1907 
 
 1 cwt. Sulphate Ammonia. 
 
 1908 
 
 3 cwt. Superphosphate. 
 
 1908 
 
 1 cwt. Sulphate Ammonia. 
 
 1909 
 
 3 cwt. Superphosphate. 
 
 1909 
 
 1 cwt. Sulphate Ammonia. 
 
 1910 
 
 
 1910 
 
 1 cwt. Sulphate Ammonia. 
 
 1911 
 
 3 cwt. Superphosphate. 
 200 lb. Sulphate Potash. 
 
 1911 
 
 1 cwt. Sulphate Ammonia. 
 200 lb. Sulphate Potash. 
 
 1912 
 
 
 1912 
 
 1 cwt. Nitrate Soda. 
 
H. — Little IIoos Field. Plan of Rotation Plots arranged to test the Besidtuil Value 
 of various Manures — one, tivo, three, and four years after their application. 
 
 9 
 
 t— 1 
 
 o 
 o 
 
 
 B 
 
 C 
 
 (2) 
 
 H 
 
 Dung 
 
 {ordinary) 
 
 16 tons per acre 
 
 1307, 'II, '15 
 
 Dung 
 
 (Cake-fed) 
 
 16 tons per acre 
 
 1807, 'II, 'IS 
 
 6 
 Shoddy 
 
 I ton per acre 
 J 307, 'II, 15 
 
 5 
 
 Guano 
 
 8 C)vt per acre 
 
 1907, 'II. '15 
 
 Superphosphate 
 
 6001b per acre 
 1307, 'II, '15 
 
 Bone Meal 
 
 ^50 lb per acre 
 
 1907. 'II. '15 
 
 5 
 
 4 
 Dung 
 
 (ordinary) 
 
 1 6 tons per acre 
 
 1906. '10. 74 
 
 Dung 
 
 (Cake- fed) 
 
 16 tons per acre 
 
 1906, '10, /4 
 
 Rape-ceLke 
 
 1 cwt per exre 
 1907. 'II, '15 
 
 Superphosphate 
 
 600 lb per acre 
 1906, '10, 74 
 
 Bone Meal 
 
 430 lb per acre 
 1906. '10. 74 
 
 Basic Slag 
 
 6001b. peracre 
 1907, 'II, 15 
 
 3 
 Dung 
 
 (ordinary) 
 
 16 tons per acre 
 1905, '09.' 13 
 
 3 
 Dung 
 
 (Cake fed) 
 
 1 6 tons peracre 
 
 ign^-. '09. '13 
 
 
 3 
 
 Guano 
 
 8 cwt per acre 
 1906, "10, 14 
 
 Rape-cake 
 
 10 cwt peracre 
 1906, '10, '14 
 
 Superphosphate 
 600 lb per acre 
 1905, '09. 13 
 
 
 Basic Sla^ 
 
 600 lb. peracre 
 1906, '10, 14 
 
 (U Dung 
 
 (ordinary) 
 
 / 6 tons per acre 
 
 1904. -OS. "/ 
 
 ■,^:i<:^^. .^. f.^y^^y. 
 
 2 
 
 Shoddy 
 
 / ton per acre 
 1905, '09, '13 
 
 2 
 
 Guano 
 
 8 cwt per acre 
 1905, '09, 13 
 
 Rape-ccike 
 
 10 cwt per acre 
 
 Superphosphate 
 
 600 ih. per acre 
 1904, '08. '12 
 
 Bone Meal 
 
 430 lb peracre 
 1905, '09. 13 
 
 Basic Slag 
 
 600 lb. per acre 
 1905. '09. '13 
 
 II) Dung 
 
 (Cake-fed) 
 
 l6tons perdjcrp 
 
 1904. '08. '12 
 
 Shoddy 
 
 / ton per acre 
 1 9 04. '08, 12 
 
 I 
 
 Guano 
 
 8 cwt per axre 
 1904, V8, 12 
 
 Rape-caJ<e 
 
 10 cirt per acre 
 1904. 'OS. '12 
 
 Bone Meal 
 
 430 lb. per acre 
 1904, '06, '12 
 
 Basic Slag 
 
 600 lb. per acre 
 1904, 'OB. '12 
 
 t§. 
 
 ,etq 
 
 "^•s 
 •e s 
 
 i^ 
 
 
 -« s 
 
 
 Adjoins Broadbalk Field. 
 
 Area of each plot, |th acre. 
 
 Series A deals with the residual effects of Ordinary Dung. 
 
 » B ,, ,, ,, Cake-fed Dung. 
 
 »» C ,, ,, ,, Shoddy. 
 
 ». D ,, ,, ,, Guano. 
 
 »» E ,, ,, ,, Rape Cake. 
 
 5» f M ,, ,, Superphosphate. 
 
 .» G „ ,, ,, Bone-Meal. 
 
 >» H ,, ,, ,, Basic Slag. 
 
 In each series the manure is applied to one plot in 1904 and each successive fourth 
 year, to another plot in 1905 and each successive fourth year, to a third plot in 1906 and 
 each successive fourth year, and to a fourth plot in 1907 and each successive fourth year. 
 All the plots in the Series A to E, which deal with Nitrogenous Manures, receive, as 
 necessary, equal amounts of Phosphates and Potash. Similarly, all the plots in the 
 Series F, G, H, dealing with Phosphatic Manures, receive equal dressings of Nitrogenous 
 or Potassic Manures as required. 
 
 (1) In 1912 only 10 tons 8 cwt. per acre of ordinary and cake-fed Dung respectively 
 was applied, instead of 16 tons as in previous years. 
 
 (2) In 1908 and since, the Nitrogenous Manures applied to the plots of Series C, D, and 
 E have been as follows — 
 
 Series C. Shoddy, 957 lb. = 50 lb. N. peracre. 
 
 „ D. Peruvian Guano, 777 lb. = 50 lb. N. 
 „ E. Rape Cake, 1036 lb. = 50 lb. N. 
 
 Check plots receiving in Series A to E no Nitrogen throughout, 
 Series F to H, no Phosphates throughout. 
 
 ^ 
 
RESIDUAL VALUE OF VARIOUS MA?^U5lE9 
 
 47 
 
 Table XXTTI. — Total Produce, Grain and St) aw, or Roots and Leaves, per acre. 
 
 OF THE 
 *. COLLEGE OF^ 
 
 :^Gr,cULT^ 
 
 Series 
 and 
 Plot. 
 
 Manuring. 
 
 00 
 
 52 
 
 03 
 
 <a 
 
 0-52 
 
 
 S2 
 
 •ad 
 
 •3 . 
 
 «2 
 
 2=2 
 ^2 
 
 
 • 
 
 Tons. 
 
 Lb. 
 
 Tons. 
 
 Lb. 
 
 Tons. 
 
 Lb. 
 
 Lb. 
 
 Tons. 
 
 Bush. 
 
 Al 
 
 Unmanured .... 
 
 10-3 
 
 2323 
 
 17-1 
 
 3650 
 
 14-0 
 
 3792 
 
 2270 
 
 11-6 
 
 19-4 
 
 2 
 
 Dung, ordinary (1904, '8, '12) 
 
 131 
 
 4619 
 
 18-2 
 
 4673 
 
 191 
 
 5128 
 
 2572 
 
 13-9 
 
 84-3 
 
 3 
 
 (1905 &'9) . 
 
 8-8 
 
 3501 
 
 17-5 
 
 5393 
 
 14-5 
 
 5644 
 
 2681 
 
 14-1 
 
 26-9 
 
 4 
 
 (1906 & '10) 
 
 8-8 
 
 2269 
 
 18-2 
 
 5471 
 
 15-5 
 
 4057 
 
 2406 
 
 12-5 
 
 29-2 
 
 5 
 
 (1907 & '11) 
 
 9-8 
 
 2402 
 
 14-9 
 
 6908 
 
 17-3 
 
 4581 
 
 2358 
 
 15-8 
 
 26-8 
 
 Bl 
 
 Dung, cake-fed (1901, '8, '12) 
 
 16-7 
 
 4177 
 
 19-4 
 
 4319 
 
 22 4 
 
 5362 
 
 2386 
 
 14-1 
 
 85-6 
 
 2 
 
 Unmanured .... 
 
 10-0 
 
 2417 
 
 16-2 
 
 4025 
 
 14-3 
 
 3862 
 
 2261 
 
 12-0 
 
 21-8 
 
 3 
 
 Dung, cake-fed (1905 & '9) . 
 
 9-5 
 
 5530 
 
 18-5 
 
 5497 
 
 14-2 
 
 6641 
 
 2921 
 
 14-2 
 
 29-4 
 
 4 
 
 (1906 & '10) 
 
 11-4 
 
 2772 
 
 25-6 
 
 6489 
 
 16-9 
 
 4400 
 
 3502 
 
 14-4 
 
 26-5 
 
 5 
 
 (1907 & '11) 
 
 9-4 
 
 2649 
 
 14-4 
 
 9407 
 
 190 
 
 4298 
 
 2369 
 
 171 
 
 31-4 
 
 CI 
 
 Shoddy (1904, '8, & '12) . 
 
 14-7 
 
 3656 
 
 21-0 
 
 4667 
 
 19-7 
 
 3969 
 
 2295 
 
 11-4 
 
 28-4 
 
 2 
 
 (1905 & '9) . 
 
 11-1 
 
 4363 
 
 23-6 
 
 4550 
 
 16-3 
 
 4558 
 
 2387 
 
 11-6 
 
 26-1 
 
 3 
 
 Unmanured .... 
 
 10-6 
 
 2.'i88 
 
 17-7 
 
 4334 
 
 15-1 
 
 3850 
 
 2561 
 
 11-7 
 
 24-2 
 
 4 
 
 Shoddy (19(16 & '10) . 
 
 10-7 
 
 2512 
 
 24-2 
 
 6231 
 
 19-1 
 
 4466 
 
 3461 
 
 140 
 
 30-4 
 
 5 
 
 (1907 & '11) . 
 
 10-3 
 
 2615 
 
 16-9 
 
 7495 
 
 22-2 
 
 5448 
 
 2560 
 
 14-7 
 
 29-8 
 
 Dl 
 
 Guano (1904, '8, & '12) 
 
 14-6 
 
 2550 
 
 20-1 
 
 4056 
 
 20-9 
 
 3608 
 
 1742 
 
 10-5 
 
 28-8 
 
 2 
 
 (1905 & '9) 
 
 11-0 
 
 5176 
 
 19-7 
 
 4165 
 
 15-3 
 
 6884 
 
 2114 
 
 11-5 
 
 24-1 
 
 3 
 
 (1906 & '10) . 
 
 10-9 
 
 2857 
 
 25-6 
 
 4846 
 
 15-9 
 
 4053 
 
 3392 
 
 11-1 
 
 22-5 
 
 4 
 
 Unmanured 
 
 10-6 
 
 2985 
 
 18-7 
 
 4618 
 
 17-4 
 
 4510 
 
 2739 
 
 11-8 
 
 26-9 
 
 5 
 
 Guano (1907 & '11) . 
 
 10-6 
 
 2680 
 
 17-4 
 
 7375 
 
 15-7 
 
 4014 
 
 2374 
 
 14-2 
 
 26-3 
 
 E 1 
 
 Rape Cake (1904, '8, & '12) . 
 
 14-1 
 
 2674 
 
 17-8 
 
 3887 
 
 19-7 
 
 3750 
 
 2180 
 
 10-7 
 
 27-7 
 
 2 
 
 (1905 & '9). 
 
 11-2 
 
 4185 
 
 17-9 
 
 4326 
 
 15-1 
 
 5203 
 
 2242 
 
 11-7 
 
 22-3 
 
 3 
 
 (1906 & '10) 
 
 9-5 
 
 2645 
 
 22-7 
 
 4684 
 
 14-5 
 
 3866 
 
 3486 
 
 11-5 
 
 22-2 
 
 4 
 
 (1907 & '11) 
 
 10-5 
 
 2734 
 
 19-4 
 
 6619 
 
 15-2 
 
 4661 
 
 2516 
 
 14-5 
 
 25-1 
 
 5 
 
 Unmanured 
 
 10-8 
 
 2769 
 
 19-5 
 
 4527 
 
 14-7 
 
 4155 
 
 2784 
 
 12-7 
 
 21-1 
 
 Fl 
 
 Unmanured .... 
 
 11-7 
 
 3132 
 
 22-9 
 
 4749 
 
 14-1 
 
 4814 
 
 3166 
 
 8-7 
 
 31-6 
 
 2 
 
 Superphosphate (1904, '8, '12) 
 
 12-2 
 
 3025 
 
 23-2 
 
 5064 
 
 16-9 
 
 4726 
 
 3223 
 
 10-9 
 
 33-4 
 
 3 
 
 (1905 & '9) 
 
 10-2 
 
 3949 
 
 V3-6 
 
 4956 
 
 14-ti 
 
 4973 
 
 2922 
 
 11-7 
 
 31-9 
 
 4 
 
 (1906 & '10) 
 
 9-7 
 
 3913 
 
 24-1 
 
 5419 
 
 16-0 
 
 5280 
 
 2682 
 
 12-8 
 
 34-9 
 
 5 
 
 (1907 & '11) 
 
 9-7 
 
 4221 
 
 23-6 
 
 5698 
 
 16-4 
 
 5641 
 
 3190 
 
 14-2 
 
 35-4 
 
 Gl 
 
 Bone-Meal (1904, '8, & '12). 
 
 12-9 
 
 3176 
 
 23-1 
 
 5203 
 
 16-7 
 
 4445 
 
 3345 
 
 9-9 
 
 32-8 
 
 2 
 
 (1905 & '9) 
 
 10 1 
 
 3636 
 
 22-1 
 
 5821 
 
 14 3 
 
 4922 
 
 36.^.7 
 
 9-9 
 
 32 7 
 
 3 
 
 Unmanured .... 
 
 10-2 
 
 3495 
 
 20-6 
 
 5491 
 
 12-7 
 
 4247 
 
 3701 
 
 9-2 
 
 29-0 
 
 4 
 
 Bone-Meal (1906 & '10) 
 
 9-9 
 
 3450 
 
 22-6 
 
 6043 
 
 14-2 
 
 4711 
 
 3263 
 
 10-5 
 
 31-8 
 
 5 
 
 (1907 & '11) 
 
 9-2 
 
 3525 
 
 22-1 
 
 6276 
 
 19-9 
 
 5285 
 
 3512 
 
 12-6 
 
 34-4 
 
 HI 
 
 Basic Slag (1904, '8, '12) . 
 
 11-8 
 
 4400 
 
 20-5 
 
 6285 
 
 13-8 
 
 4182 
 
 3564 
 
 11-5 
 
 85-7 
 
 2 
 
 (1905 & '9) . 
 
 10-4 
 
 4002 
 
 21-3 
 
 5930 
 
 13-6 
 
 4530 
 
 3^96 
 
 12-0 
 
 33-7 
 
 3 
 
 (1906 <^ '10) 
 
 9-4 
 
 3662 
 
 21-4 
 
 5860 
 
 13-6 
 
 4431 
 
 3943 
 
 12-5 
 
 29-1 
 
 4 
 
 (1907 & '11) 
 
 9-1 
 
 3624 
 
 17-0 
 
 5816 
 
 14-4 
 
 3860 
 
 3804 
 
 120 
 
 32 5 
 
 5 
 
 Unmanured 
 
 8-6 
 
 3293 
 
 17-4 
 
 5933 
 
 11-4 
 
 4511 
 
 4005 
 
 10-5 
 
 30-1 
 
 The yields on the plots to which the manure was applied in any given year are printed in heavier type. 
 
 * Dressed Grain only. 
 
The Incorporated Society for Extending the 
 Rothamsted Experiments in Agricultural 
 
 Science 
 
 Chairman 
 His Grace THE DUKE OF BEVONSHIRE, P.C, 
 J. V. MASON, Esq., M.P. (Vice-Chairman). 
 Dr HUGO MULLER, F.R.S. (Treasurer). 
 Prof. H. E. ARMSTRONG, LL.D., F.R.S. 
 R. H. BIFFEN, Esq., M.A. 
 Dr H. T. BROWN, F.R.S. 
 J. B. PARMER, Esq., M.A., F.R.S. 
 ROBERT MOND, Esq. 
 
 The Most Hon. The MARQUESS OF LINCOLN- 
 SHIRE, K.G., P.C. 
 
 Right Hon. Sir JOHN BRUNNER, Bart., 
 
 P.C. 
 Captain J. A. MORISON. 
 Sir W. S. PRIDBAUX. 
 Dr A. B. RENDLB, M.A., F.R.S. 
 Sir J. H. THOROLD, Bart. 
 Dr J. A. VOELCKER, M.A. 
 J. MARTIN WHITE, Esq. 
 E. J. RUSSELL, D.Sc. (Hon. Secretary). 
 
 'TpHIS Society collects Donations and Annual Subscriptions for 
 -*- the purpose of extending the Rothamsted Experiments- 
 The donations enable the Committee to qualify for Capital Grants 
 from the Development Fund, while the subscriptions form a valuable 
 contingency fund for meeting unforeseen expenditure arising out of 
 new work without the necessity for curtailing old work. 
 
 Subscriptions and donations should be sent to the Secretary, 
 Rothamsted Experimental' Station, Harpenden. 
 
 PRINTED BY OLIVER AND BOYD, EDINBCEOH. 
 
For a General Account of the whole of the Experimental 
 Work at Kothamsted, see 
 
 The Book of the Rothamsted Experiments 
 
 By A. D. HALL, M.A., F.R.S. 
 
 Published by JOHN MURRAY, London, 1905 
 10/6 net 
 
W O'ilBl 
 
 299650 
 
 \j iyy(Ayu^^^^.^<^-<-^ ' 
 
 I— 
 
 UNIVERSITY OF CALIFORNIA LIBRARY