12 PLANTS OF NEW ZEALAND 



necessary to take special steps at great expense, to re-forest 

 the upper mountain slopes. In New Zealand, the Forestry 

 Department, with admirable foresight, has already secured a 

 number of climatic reserves on mountain summits. These 

 will have to be fenced off to secure the exclusion of sheep and 

 cattle, for sucli animals work irretrievable havoc in the forest 

 undergrowth, and to them must be attributed much of the 

 apparent decadence of the natural forests. Wherever they 

 have secured admission to the dense bush, seedlings and young 

 trees are soon trodden under foot, broken down, and killed : 

 light is let in, and tlie bush gradually decays and disappears. 



The Destruction of the Forest. 



As we have already seen, much of the tussock country of 

 the South was at one time forest-clad. The evidence of 

 charred logs on or below the surface of the ground, proves that 

 some of it, at any rate, was cleared by fire in recent times. 

 This may have been started spontaneously, or may have been 

 the w^ork of pre-historic dwellers in the land. The Maoris in 

 the South Island have a tradition that when the Te Rapuwai 

 tribe spread over the country, Invercargill was submerged by 

 water, the forests of Canterbury and Otago were destroyed by 

 fire, and the Moa was exterminated. Canon Stack put this in 

 his list of uncertain traditions ; but there is at least nothing 

 inherently improbable in the destruction of these forests about 

 this time. In Auckland, the presence of the kauri gum in vast 

 areas now treeless, or occupied only by the manuka and 

 other heath plants, is proof that at one time the kauri forests 

 were of much greater extent than at present. The cause of 

 their disappearance is unknown. 



Whatever may have been the causes in the past, affecting 

 the reduction or increase of forest areas, they fall into insig- 

 nificance compared with the changes artificially wrought since 



