522 J. w. BEws. 



herbs and shrubs grow up with occasionally here and there 

 single trees that have resisted the fire. Xymalos mono- 

 spora often survives where all the other trees have dis- 

 appeared. 



The whole ground becomes covered with a type of plant 

 association similar to the outside transitional belt between 

 bush and veld, such as : 



Eubus pinnatus, Chilianthus dy ssophyllus Berk- 

 heya spp., Athanasia acerosa, Plectranthus spp., 

 Buddleia salvitefolia, Asparagus medioloides, Pteris 

 aquilina, with a mixture of veld grasses — Andropogon 

 species chiefly — and associated plants of the veld. 



If such an area is carefully protected the bush will grow 

 again, but this seldom happens. The annual grass fir6s 

 sweep through and destroy the young trees, and the bush 

 clearing tends to become grassland. 



Retrogression iu the Bush. — We can note, therefore, 

 the following stages of retrogression in the bush : 



First, we have the larger midland type of bush, which 

 varies slightly in its composition in different localities, but is 

 of the same general oecological character throughout. 



Secondly, we have the smaller scattered areas of bush, 

 usually confined to the upper ends of the small stream 

 valleys, the composition of Avhich is similar to the outside 

 margin of the larger bush, from which, however, it slightly 

 differs cecologically, owing to the fact that it is more open 

 and irregular, and more light penetrates. 



Thirdly, the bush has often been destroyed by fire, and in 

 place of it we get the bush clearing. 



Lastly, by constantly recurring grass fires, renewal of the 

 bush is prevented, and any surviving shrubs and trees are 

 destroyed, and the area becomes veld, though from the 

 nature of the ground it remains of the unstable variety 

 (Andropogon associations with large numbers of the 

 associated veld plants). 



