Fertility of some Colonial Soils. 



21 



exceed -1. The average percentages of the reserve plant food in 

 these 46 sandstone soils are as follows : — 



Lime 034 



Potash 031 



Phosphoric oxide 036 



Lying conformably above the Table Mountain sandstone are beds 

 of what is known as the Bokkeveld series. These consist of 

 alternate layers of shales and sandstones, the lower bands of the 

 series being fossiliferous. It would, perhaps, have been difficult to 

 predict, without previous practical agricultural experience, what 

 would be revealed by chemical analysis of soils derived entirely from 

 the Bokkeveld beds ; nor is it easy to tabulate — bearing in mind the 

 circumstances under which the samples were collected — a list of soils 

 formed solely from the beds in question ; for, to the reasons which 

 operate against this in other cases, there must here be added this — 

 that the Bokkeveld beds occur mostly in valleys, and the resulting 

 soils are, therefore, as a general rule, diluted or otherwise influenced 

 by the disintegration and decomposition of the rocks composing the 

 surrounding hills and mountains. Hence there are very special 

 difficulties involved in sorting out many Bokkeveld soils that could 

 really be called typical from the samples that have been dealt with 

 in our laboratories. I have, however, made a choice of eighteen, 

 which may fairly be considered to represent solely Bokke veld- 

 derived soils ; the results of the analyses of these are given in the 

 following table : — 



VIII. BOKKEVELD SOILS. 



Serial 

 No. 



112 

 113 

 114 

 115 

 116 

 117 

 118 

 119 

 120 

 121 

 122 

 123 

 124 



125 

 126 



127 

 128 

 129 



Division. 



Ladismith.. 

 Robertson.. 



Swellendam 



Uniondale... 



Worcester.. 



Farm. 



Buffelsfontein 



Harmonie I 



Harmonie II 



Het Kruis 



Baden 



Poortfontein 



Uitvlugt 



Doom Bivers Vallei 



Lemoens Hoek 



Kamanassie Wagen 



Drift 



Wilgehouts Rivier ... 



Roode Heuvel 



Keurbosch Kloof 



Stinkfontein 



Fine 

 Earth. 



83-9 

 80-8 

 95-2 

 49-3 

 94-7 

 62-7 

 81-0 

 72-8 

 80-3 

 89-0 



57-9 

 93-2 

 817 

 71-7 

 79-0 

 70-6 



Water, 



1-66 

 1-23 

 1-07 

 113 

 1-49 

 1-93 

 1-28 

 •31 

 2-04 

 121 

 118 

 1-21 



1-54 

 1-09 



•87 



•96 



•98 



1-64 



Organic 



Matter. 



4-97 

 5^41 

 3-92 

 4-64 

 5^71 

 5^28 

 6-07 

 1^32 

 692 

 5-76 

 5-95 

 5^69 



7^10 

 4-96 

 3-34 

 4-67 

 3-89 

 6-65 



Lime. 



•150 

 •122 

 •564 

 •114 

 •742 

 •808 

 •600 

 •046 

 2-518 

 •042 

 •106 

 •170 



•102 

 •048 

 •098 

 •136 

 •442 



Potash. 



274 

 153 

 095 

 250 

 202 

 331 

 247 

 176 

 416 

 262 

 272 

 197 



182 

 212 

 255 

 164 

 139 



Phos- 

 phoric 

 Oxide. 



•073 

 •079 

 •047 

 •120 

 •193 

 •148 

 •139 

 •036 

 •234 

 •134 

 •151 

 •122 



•095 

 •104 

 •122 

 •086 

 •077 

 •156 



On comparing the above table with the preceding one, it imme- 

 diately becomes plain how greatly these Bokkeveld soils differ from 



