10 PLANTS OF NEW ZEALAND 



profusion. It would then almost seem as if the vegetation of 

 a tropical island from the warm Southern Seas had been 

 dropped in amongst our more sombre flora, for these three plants 

 all bring with them suggestions of a warmer land than this. 

 Indeed, some have said, basing their statements on this and 

 similar facts, that the climate of New Zealand has been, in 

 recent geological times, much warmer than at present. They 

 endeavour to strengthen their argument by adducing in 

 support of it, the evidence afforded by the profusion of 

 climbers and twiners, which often render the bush an almost 

 impenetrable jungle. However, conclusions as to past climate 

 based only on present characteristics of mature plants are of 

 little value. The true explanation of the resemblance between 

 our forests and those of sub-tropical regions is to be found in 

 the fact that nearly all our bush trees are of Melanesian 

 origin. The beeches are the most important exceptions to 

 this rule. 



The Natural Permanence of the Bush. 



Another erroneous opinion is that the bush is impermanent ; 

 that it actually flies before the advancing footsteps of civili- 

 zation. It is said that whenever tracks are cut through it, 

 decay sets in on both sides, the undergrowth dies, the ferns 

 and mosses disappear, and even the trees themselves become 

 gaunt and misshapen, and their leaves few and tattered. This 

 statement can only be regarded as incorrect. Even in the 

 drier districts where the trees are struggling against very 

 adverse conditions, a forest that has been " cut out " will, in 

 time, replace itself, if not subjected to the interference of man 

 and other animals. Surveyors' tracks through damp bush are 

 soon overgrown when left undisturbed ; and, as Dr. Cockayne 

 has shown, a burnt area is soon re-forested, in the wetter 

 districts at least, though not necessarily retaining the same 

 predominant species. 



