REPORT OF THE CHEMIST 51 



SESSIONAL PAPER No. 16 



THE IMPROVEMENT OP MUCK SOILS. 



Large deposits of swamp or black muck occur in Ontario and the eastern pro- 

 vinces, as well as in British Columbia. The reclamation of these swamps and the 

 conversion of the muck into a fertile soil are consequently matters of considerable 

 importance, though not infrequently found to be problems of great difficulty. 

 Thorough drainage is, of course, necessary at the outset to get rid of the excess of 

 water and allow aeration, indispensable for correcting the sourness so characteristic 

 of the native muck. The settling also that follows drainage vastly improves its 

 mechanical condition. 



For the past twelve years experiments ha.-e been conducted in connection with 

 the improvement of such soils, and our experience goes to show that while 

 the same general principles are applicable to all, a considerable amount of experi- 

 mental or trial work must be done on the area about to be reclaimed before the most 

 effective method can be ascertained. Our experiments have included : (1) the addi- 

 tion of sand and clay, singly and together. Many mucks by this treatment have been 

 converted into excellent loams, the improvement apparently being largely due to 

 the mechanical alteration of the soil ; (2) The addition of the mineral constituents of 

 plant food — potash, phosphoric acid and lime. These have been applied in the form 

 of potash salts (muriate, &c.) and phosphates, separately and in admixtures. Wood 

 ashes also have been tried, as well as simple dressings of lime. Most encouraging 

 results in the majority of instances have been obtained from thus supplying the lack- 

 ing mineral elements, and especially from the application of those mixtures which by 

 their alkalinity serve to neutralize the muck's acidity; (3) An application of stable 

 manure or good loam. Although muck is practically organic matter and is rich in 

 nitrogen, it has been found that at the outset (and after the drainage and settling of 

 the muck) such an application has proved very beneficial. This, we conclude, is due 

 rather to the introduction of desirable soil bacteria than to the small amounts of 

 plant food thus supplied. 



THE VALUE OF LEGUMES FOE THE IMPROVEMENT OF SOILS. 



If the crop-producing power of a soil is to be maintained or increased, due regard 

 must be given to cultivation, rotation and manuring. These are the means whereby 

 a favourable physical texture is assured and a supply of immediately assimilable 

 plant food is obtained. In connection with the last mentioned of these factors, this 

 Division has been specially engaged for the past fifteen years on the study of the 

 legumes- as soil enrichers. Almost every possible phase of the subject has been in- 

 veetigated. 



The particular value of the legumes (clover, alfalfa, peas, beans, &c.), for 

 manurial purposes lies in the fact that they are able to appropriate and store up free 

 nitrogen from the atmosphere. This they are enabled to do through the agency or 

 co-operation of certain germs or bacteria present in the soil, and which attaching 

 themselves to the roots of the legumes form thereon nodules or tubercles in which they 

 subsequently reside. The nitrogen of the air in the soil is absorbed by these germs, 

 elaborated into nitrogenous compounds and passed on to the circulation and tissues of 

 the host plant — the legume. On turning the crop under, the natural decomposition 

 that follows enriches the soil in compounds that will, under favourable climatic in- 

 fluences, subsequently furnish nitrogen in forms available for plant growth, and thus 

 increase in the yield of succeeding crops. The benefit to be derived from green 

 manuring ' (as this use of the crop is termed) is not confined to this addition to the 

 soil's nitrogen content — there is the production of a large amount of humus-forming 

 material with all its valuable functions, chemical and physical, and the setting free in 

 a pre-digested form of considerable amounts of the mineral constituents of plant food. 



