6i6 Journal of Agnciilture. Mctoria. [loOcT.. 1912-- 



activity, and the improvement of the mechanical condition of the soil. Its 

 destructive effect is due to its caustic character. It rapidly destroys humus, 

 and thus tends to rob the soil of its most valuable constituent. According 

 to the Pennsylvania experiments quoted above, this loss was equivalent to 

 the loss of 375 lbs. of nitrogen per acre in the first 9 inches of soil in 

 sixteen vears, i.e. equal to 37^ tons of stable manure per acre. Hence, in' 

 liming, provision must be made for the restoration of this organic matter 

 by green manuring or the use of organic manures, like farmyard manure,, 

 and also by the avoidance of stubblt- burning. 



Furthermore, on soils deficient in organic matter, ground limestone or 

 dilute lime should be used in preference to caustic lime. 

 (2) There is an old couplet which runs — 



" Lime and lime without manure 

 Make both farm and farmer poor." 



Liming must not l)e regarded as a substitute for manuring. Phosphates 

 nnist be used in conjunction with lime to secure the best results, and the 

 supply of organic matter or humus must also be maintained. Unless these 

 points are borne in mind, liming will deplete the soil of its fertility. 



When does a Soil need Lime. 



1. The nature of the vegetation often indicates whether lime is wanting 

 or abundant in a given soil. The habitual presence in the crops of such 

 weeds as sorrel and plantain, which are fairlv tolerant of acid soil con- 

 ditions, is an indication of the lack of lime, just as the continual appear- 

 ance of vigorous clovers and trefoils in the pastures is a fair indication of 

 the presence of a sufficiency of lime. The nature of the vegetation is a 

 reliable, but not an infallible indication of the requirements of a soil as 

 regards to lime. 



2. There are several simple tests which roughly indicate whether or 

 not a soil is in need of lime. If a soil is acid or sour in character, it is 

 deficient in lime. A rough practical method of determining whether a given 

 .soil is acid is to take a strip of blue litmus paper (which may be purchased 

 from, any druggist), and place it between the broken halves of a ball of 

 moist soil. If, after standing for some little time, the litmus turns red in 

 colour, the soil is clearly acid in character and in need of lime. 



3. If a soil contains a sufficiency of lime in the form of carbonate, it 

 cannot be acid in character. A rough test of the amount of carbonate of 

 lime in a soil may be made by taking a hollowed out ball of soil and pour- 

 ing in a few drops of strong spirits of salts or hydrochloric acid. If much 

 lime in the form of carbonate exists, a brisk effervescence will take place, 

 while, if small quantities only are present, only a few bubbles will 

 appear. 



4. Some idea of the requirements of a soil for lime may be gained by 

 studying its chemical analysis. The total amount of lime present in the 

 the soil may be determined with accuracy by chemical analysis, but such 

 analysis can throw little light on the form in which the lime is present. 

 If the greater portion of the lime is present in the form of phosphate, or 

 silicate, or sulphate, it will be of practically little value in keeping the 

 soil " sweet." Paradoxical as it may appear, some soils known to contain 

 large quantities of lime have given increased returns when dressed with 

 this ingredient ; whilst, conversely, some soils with a relatively low per- 

 centage of lime have proved unresponsive to further applications. Hence 

 the form in which the lime is pre.sent, rather than its total amount, is 

 the important factor in deciding whether lime is required. The four 



