74 Journal of A.gricnUitrt\Yicioria. [lo Feb., 1911. 



of the Tussock Grass. The average composition of the corresponding 

 parts of cereals, grasses, and cultivated plants of economic value would vary 

 from .4 to 1.4 per cent, phosphoric acid, or nearly ten times as much. 

 It would therefore appear that the native plants have established 

 a kind of equilibrium in phosphoric acid with the soil. They require 

 very little from it, and return to it correspondingly small amounts when 

 they decay. It is quite possible that in Europe and America the animal 

 has had a further action in determining the character of the soil, for 

 by a process of the survival of the fittest, those plants which produced 

 most phosphoric acid would be likely to be selected as food by the 

 animal, and the struggle for existence being thus intensified amongst 

 them, the more vigorous varieties would gradually be evolved. It appears 

 then that native vegetation, when not interfered with in any way by the 

 animal, neither produces nor requires as high a percentage of phosphoric 

 acid in its tissues as is the case with those plants which have proved of 

 the greatest economic value both to the higher animals and to man. 



It appears to me that the results of the above analyses explain the 

 occurrence of the bone diseases comprehended under the names of 

 " Cripples " and " Coast Disease," which affect animals kept too long 

 on "Kangaroo Grass," and similar grazing country. The native vege- 

 tation only contains one-tenth of the amount of phosphoric acid that Rye 

 Grass, Cocksfoot, Lucerne, Clover and the cultivated cereals produce off 

 the same soil. These facts also explain the general usefulness of phos- 

 phatic manures on Australian soils. 



In five localities on the coastal plain, experimental farms have been 

 carried on by the Department in order to investigate the problems of 

 bringing these poor soils into profitable use. 



It is necessary to state that a vast difference is found in districts of 

 light and heavy rainfall where the chemical composition of the soil is 

 nearly identical. In the former a crop can be grown successfully with 

 a light dressing of superphosphates immediately after the scrub is rolled 

 and burned. When the rainfall exceeds 35 inches, after the land has 

 been drained, it requires to be exposed to the sun and air for two or 

 three seasons before it is suflSciently sweetened to produce any satisfactory 

 growth. The fibrous rootlets with which these sandy soils are filled 

 decay very slowly. The .soil is invariably acid, and the roots of the 

 native vegetation seem to produce an exudate which interferes with the 

 growth of other plants. At all events, in our experimental plots, seeds 

 germinate, but although abundantly supplied with moisture, and arti- 

 ficially supplied with nitrogen, phosphoric acid, and potash, they fail to 

 establish themselves after the food supply, contained in the seed, is 

 exhausted. Lime and ashes help to rectify these conditions, but the 

 only way in which they can be quickly overcome is by the addition of 

 farmyard manure to the soil. 



This undoubtedly acts by introducing putrefactive and other bacteria, 

 which appear to be singularly deficient in the soil in its original state. 

 Potatoes and mangolds are probably the first crops to give a satisfactory 

 yield, oats and rye following next, and peas and beans being much more 

 difficult to adjust to the new conditions. Finally, the experience of the 

 past 60 years goes to show that the market gardeners in the neighbour- 

 hood of Melbourne have successfully solved all the difficulties of bringing 

 such lands into profitable cultivation, and converting them into some of 

 the most productive areas of our State. The results of our experimental 

 work clearly indicate the lines along which success must be achieved. 



I 



