II Jan., 1909.] Problem of our Z'nproductive Lamds. 19 



of the bacteria existing within the manure of the animal. It will thus 

 be seen that under the existing conditions of Victorian climatic inliuences 

 it is certain that farming may be carried on profitably and the fertility 

 of the land Ims steadily increased as far as these two es.sential ingredients 

 are concerned. 



In regard to phosphoric acid, this is the plant food whose absence gives 

 the character to the vegetation on the poor lands. It is present in very 

 small amounts — amounts so small that from chemical analysis alone much 

 of our soil would be classed by European and American standards as very 

 close to the point of inefficiency. Moreover there is very little difference 

 in the amounts found in the surface soil and the subsoil ; frequentlv in 

 fact if cla\- is met with a few^ feet below the sand) surface the percentage 

 of phosphoric acid at once undergoes ai marked increa.se. I am inclined to 

 think that its peculiarity of the practical identity of the surface and the 

 subsoil is a character which marks off Australian soils from those of the 

 old world, just as clearly as the prevailing characteristics of our plants and 

 animals. Very probably indeed all three are associated, and because our 

 plants and animals retained the type of tho.se of the mesozoic geological 

 ages in the other continents, our surface soils have failed to become pro- 

 gressively richer with regard to phosphoric acid. Perhaps our climate 

 has had its share in the want of development, but whatever may be the 

 cause, of the fact itself there can be no question or dispute. 



The Plant Food Available in the Soil. 



An examination of these soils indicates that while they differ somewhat 

 from one another, they all have the same characteristics. In the coastal 

 plain, the prominent features are the variations in the amount of nitrogen 

 and potash. In the case of nitrogen the amount varies chiefly in conse- 

 quence of the character of the vegetation. Many of these plains are very 

 wet in wantex ; the rank vegetation therefore gives them many of the charac- 

 teristics of peaty land. 'I'he surface is occupied by a dense fibrous net- 

 work of roots, extending for 6 to 12 inches below the surface. The 

 amount of organic matter consequently makes these soils very rich in 

 nitrogen. When they are turned up with the disc plough, exposed to the 

 atmosphere and allowed to sweeten, the w^hole surface breaks down into a 

 rich sandy loam. This type is seen in the best parts of the Portland heath 

 land, the Heytesbury grass tree plains, the market garden areas near 

 Brighton and Mordialloc and much of the plain country in South Gipps- 

 land. The quantity of potash varies chiefly in relation to the nearness of 

 the clay. Many of the sandy loams rest on the clay at a distance of from 

 I to 3 feet from the surface. In such cases the amount of the 

 potash is relatively large. In other cases, however, the sand is inter- 

 spersed with coarse grains of quartz or with ironstone, and the clav may 

 be several feet below the surface; in such cases the amount of potash is 

 comparatively low. With regard to phosphoric acid, the amount present 



appears to depend on the proximity of the clay subsoil. In manv cases it 

 is fairly large and the quantity is increased in the alluvial drift which is 

 found at the foot of the undulating hills and rises which are often met 

 within Southern Victoria. 



In the hill country these soils are characterized bv the relative amount 

 of potash and phosphoric acid which they contain and bv their comparative 

 poorness in nitrogen, except in the alluvial .soil at the bottom of the 

 gullies. On the hill sides the phosphoric acid usually runs from forty to 



