345 



Queensland. — We now turn to an important series of pioneering papers by Dr. 

 Jensen. I have only offered sufficient extracts and abstracts to indicate their scope, 

 and to induce my readers to peruse the originals. 



" Some Notes on the Soils and Forest Flora of the Dividing Range, north of 

 Roma, Queensland," by H. I. Jensen, D.Sc, in Queensland Agric. Journ., XVI, 239 

 (October, 1921). 



" It has been known for ages that many forest trees have a special predilection for certain kinds of 

 soil, and as the science of geology has developed, it has been noticed by field geologists in all parts of the 

 world, that certain trees are almost entirely confined to certain geological formations. So definite is the 

 dependence of some plant species on a particular rock type, that these plants can be used in field mapping, 

 as safe indications as to the formation beneath the soil on which they grow." (p. 239.) 



" It was found that the character and quality of soils were de-pendent principally on geological 

 formation, secondarily upon climate and topography. Topography is, however, as a rule, itself dependent 

 on geological formation and climate, and is therefore a factor of minor importance as compared with 

 geology and climate. 



" Thus, in coastal regions and inland regions alike, soils can be divided into geological groups, which 

 stand in the same relation to one another, as, for instance — 



Granite . . . 

 Sandstone 

 Quartz schist 



Trachyte 

 Andeeite 

 Shale ... 



Diorite . . . 



Basalt 



Calcareous sandstone 



Calcareous shale 



Limestone 



Sandy light loams relatively poor in mineral plant-food. 

 Loams, fair in plant-food. 



Clayey soils rich in plant-food. (p. 239.) 



J 



<: The researches, however, did establish the fact that the bushman's method of judging soil by the 

 timber growing on it was thoroughly sound in principle." (p. 240.) 



Then Dr. Jensen took certain areas geographically, including Roma to Injune, 

 and subdivided it into "Box country," " Ironbark country," "Moreton Bay Ash and 

 Sugar Gum country " (the latter is Angophora lanceolata), and Basaltic Box lands," all 

 of which refer to Eucalyptus (p, 241). Box in his connection, is chiefly E. populifolia. 



The trees on the fringe of Black Soil Plains include E. populifolia. See Queensland 



Agric. Journ., November, 1921, p. 297 : — 



" Associated with Sandalwood (Eremophila Mitchelli) we usually get some Box and Silver-leaf 

 Ironbark (E. melauophloia), the latter where a stony formation gets close to the surface." (p. 298.) 



" Box Country. — The soil on which the Poplar Box holds sway is usually a grey clay soil, fair in 

 mineral plant-food, but rather too heavy for cultivation, and generally inclined to be sour. It holds water 

 well, but has poor capillary powers, differing in that respect from the Sandalwood country. . . . 



" Sometimes we get a fair amount of Poplar Box (Box) on felspathic sandstone country, where, 

 however, it is subordinate to Pine, Moreton Bay Ash (E. tessellaris), Sugar Gum {Angophora lanceolata), 

 and Tumbledown Gum (E. dealbata). This class of country is poor in lime, but a typical Box country is 

 fair in lime. . . . 



