MANUKING IN THEORY AND PRACTICE. 



351 



pared with that dug nine or eighteen inches deep in 

 tne previous year, is here shown ; — 



Manure per Acre. 



Produce per Acre. 









Turnip 

 Bulb. 



Turnip 

 Leaf. 





tC CO 



Id M 



02 M 



PI 02 



Superphosphate, 11 cwts. ) 



(Land dug 9 inches deep) . i" 

 Superphosphate, 11 cwts. \ 



(Land dug 18 inches deep) . ) 

 Superphosphate, 11 cwts. \ 



(Land ploughed) . , . j 



H o ^ 



13 8 2 



14 4 

 12 13 3 



o ^ a. 



H O =^ 



4 9 

 4 4 1 

 4 8 



03 



1-20 

 1-30 

 1-17 



These facts indicate that the extent and direction 

 of the underground range of the Turnip is very much 

 dependent on the mechanical condition of the soil : 

 the rapidity of hulb-formation and the amount of 

 crop are greatest where the land is deeply tilled. The 

 land dug nine inches deep shows a slight superiority 

 over that which is ploughed, and shows the character 

 of the conditions required in Turnip culture. It is 

 universally known that tilth is of the highest im- 

 portance to the favourable formation of bulb in root 

 crops ; and the best relation of bulb to leaf, and in 

 fact the best acreage yield of bulbs, is in the lighter 

 soils, where there is comparatively little obstruction 

 to the development of fibrous root, and it is in these 

 that the special efiicacy of superphosphate has been 

 most observable. And if the Turnip is to be valued 

 for its bulb-formation, the aim of the gardener must 

 be not to increase the above-ground organs of col- 

 lection (the leaves), but the underground fibrous 

 roots. 



Effect of Phosphates.— Much controversy 

 has recently occurred regarding the action of dis- 

 solved and undissolved phosphates, as affected by the 

 amount of f^-ee phosphoric acid supplied to the soil 

 by various artificial manures ; it will be admitted by 

 most horticulturists that, in order to be food for 

 plants, phosphate of lime, like other constituents 

 of plant-food, must be soluble to some extent in 

 water, or in the liquid which passes through the 

 medium of the root into the plant. The greater effi- 

 cacy of phosphate of lime in bones in comparison 

 with coprolite powder entirely depends upon its finer 

 state of aggregation, and consequently upon its 

 greater solubility in the form of bone-dust. 



The following results, from Dr. Andrew Aitkin's 

 report, of experiments conducted by the Highland 

 and Agricultural Society of Scotland, at Harelaw and 

 Pumpherston, confirm the opinion that there is great 

 economy in using dissolved phosphates, rather than 

 the raw material, upon those and similar soils. 



Table showing Effects of Dissolved and Undissolved 

 Phosphates upon Swedes at Harelaw, and upon Yellow 

 Turnips at Fumpherston, in the Season of 1880. 



Undissolved Phosphates. 





Swedes. 



Yellow Turnips. 





Weight 

 per Acre. 



Dry 



matter 

 per Acre. 



Weight 

 per Acre. 



Dry 

 matter 

 per Acre. 



Bone-ash 

 Ground Coprolites 

 Bone-meal . 

 Phosphatic Guano 

 Ground Apatite . 

 Ground Mineral ■) 

 Phosphates ) 



Cwts. 

 157 

 202 

 206 

 223 

 177 

 211 



Cwts. 

 16-6 

 21-2 

 21-8 

 23-8 

 18-4 



21-7 



Cwts. 

 297 

 339 

 273 

 275 

 193 



294 



Cwts. 

 24-0 

 27-1 



21- 8 



22- 

 • 13-7 



23- 2 



Average . 



196 



20-6 



278 



22-0 



Dissolved Phosphates. 



Bone-ash 

 GroundCoprolites 

 Bone-meal . 

 Phospb atic Guano 

 Ground Apatite . 

 Ground Mineral ') 

 Phosphates J 



Cwts. 

 241 

 202 

 246 

 257 

 236 



228 



Cwts. 



23- 1 



21- 



24- 8 

 26-2 

 24-7 



22- 8 



Cwts. 



385 

 310 

 308 

 334 

 390 



385 



Cwts. 

 31-6 



26- 3 

 25-2 



27- 4 



30- 8 



31- 6 



Average . 



235 



23-8 



354 



28-8 



Excess with Dis-") 

 solved Phos- > 

 phates . . J 



39 



3-2 



76 



6-8 



Thus, the increase in the crop due to the dissolving 

 of the phosphate is, at both stations, about 20 per 

 cent. ; the total amount of dry matter per acre is at 

 Harelaw 15 per cent, more, and at Pumpherston 25 

 per cent, more on the plots which received dissolved 

 phosphates, proving that the increase of crop is not 

 due to water chiefly, but also to solid matter, or sub- 

 stances useful as food. 



Effect of Manures on Swedes and Mangels, 

 Growth of Swedish Turnips, Year after Year, on the 

 same Land at Eothamsted. Fifteen Years, 1856- 

 1870. Average Froduce per Acre per Annum. 



Description of Manure. 



Without Manure . 

 Superphosphate of Lime ) 



alone . . . . ] 

 Mixed Mineral Manure. 

 Ammonium Salts, alone 

 Nitrate of Sodium , alone 

 Mix. Min. Manure and |^ 



Ammonium Salts . j 

 Mix. Min. Manure and • 



Nitrate of Sodium . f 

 Farmyard Manure 







Increase over 



Bulbs. 



Leaves. 



Unmanured. 







Bulbs. 



Leaves. 



CO to 



m 



to 00 





O ^ 





p. ^ 







O 



H O 



o 



11 



3 







2 12 



9 



2 1 



6 



2 16 



8 



2 5 



5 



13 



3 



2 







19 



4 



7 



1 



4 12 



14 



4 1 



11 



5 2 



16 



4 11 



13 



6 4 



17 



5 13 



14 



