S August, 1907.] Fiftli ConvcHtion, Chamber of Agriculture. 491 



diminished but, if anything, is increased, while a profitable income is 

 derived from the various products of the soil. It is the interest on our 

 soil capital which we should live u,pon and not on the capital itself. This 

 being" so it is somewhat surprising that many farmers operate on only such 

 a small proportion of their soil capital ox in other words only give the crops 

 they produce such limited feeding ground by imperfect methods of cultiva- 

 tion. In order tO' completely understand what is meant by the fertility or 

 producing power of the soil the following influencing factors may be 

 named : — 



1. The water holding capacity which is largely controlled by the 



presence of organic material. 



2. The porosity or natural drainage which depends upon the size 



of the soil particles. 



3. The capillary power or power to move water from the subsoil 



tO' the surface. 



4. The temperature which is regulated bv the natural powers of 



drainage, colour, and texture of the soil. 



5. The presence of plant foods. 



You will note that prominence is given to those factors which have to 

 do with the storage and retention of moisture. The most fertile soil in the 

 world is powerless to produce crops if moisture is lacking, and for that 

 reason, I direct pointed attention to the need of improvement in that direc- 

 tion in many of the heavier types of Victorian soils. Shallow cultiva- 

 tion of soils having: a stiff impervious clay subsoil means only a limited 

 storage of moisture and hence the yield is regulated almost entirely b\- the 

 amount of moisture at tlie disposal of the crop. 



The ploughing in of the remains of crops and grass roots, at all events, 

 occasionallv. is something of a set off to the extravagant burning of the 

 stubble, so unfortunatelv common in the wheat growing districts. The 

 growth of crops suitable for ploughing in or feeding off and the return of 

 animal manure to the soil are all means h\ which an improvement is effected 

 in the water holding power of the soil. Soils vary within wide limits as 

 regards fcheir natural powers of drainage, sandy soils being of course the 

 quickest in this respect and clay soils the slowest. Extremes of either type 

 are not the most prolific producers of crops. It is liowever by deep cultiva- 

 tion drainage and the use of lime, where necessary, that clay soils may be 

 assisted to store up moisture in greater quantities without rendering the 

 land cold and unproductive. 



Sandy soils have only poor capillary powers and for this reason we 

 sometimes find shallow rooted plants suffering from want of moisture, 

 although there may be an abundance within 2 feet of the surface but 

 unable to rise up to the roots of the crop. Clay soils on the other hand 

 have very strong capillary powers, and we invariably find that this type 

 rapidly forms a crust on the surface and loses m.oisture rapidly in warm or 

 windy weather. The loss of moisture is checked to a large extent by 

 keeping the surface mulched or loose thereby minimizing evaporation. 



The temperature of the soil plavs a much more important part in the 

 production of crops than many farmers give credit for. Poorly drained 

 land is always cold and slow to respond to the genial influences of spring. 

 The reason is not far to seek. Evaporation is always a cooling process 

 and when the surplus moisture has to be evaporated bv the sun's warmth 

 in the spring, growth only proceeds slowly until the land becomes warm 

 enough to permit those wonderful activities to take place which we are 

 so familiar with under the name of spring growth. The germination of 



