, 
Kin several tall trees dominant, or subdominant, whereas the ER forest. 
 originally occupying wide areas in all the botanical rn aa where a 
; Forest. | 133 
of the fittest, and the inability of juvenile trees to produce seed, turns into a. 
close forest with little undergrowth. The above are two opposite stages, each 
a distinct expression of the light-factor, the dense undergrowth marking a maxi- 
-mum and the close forest-roof a minimum. With increased illumination, hygro- 
phytes are replaced by xerophytes, so that, with an ever-increasing light-inten- 
sity, forest will be replaced by heath. Or the opposite may take place and: 
heath be the first of a series culminating in pure kauri-forest. - 
The pioneer forest-trees’are probably the species of Zepfospermum, Knightia, 
Weinmannia sylvicola, Pseudopanax crassifohum and Persoonia. Then would 
come Agathis and Podocarpus totara, and, later on, the species of Beilschmiedia. 
The kauri sub-association would thus antedate that of Berlschmiedia. With a 
constant .climate, the forest would slowly change and reach its climax; then, 
the old trees dying, the light-intensity would increase, seedlings could grow and 
rejuvenation gradually come about. But should the climate become EN heath- 
BBNEOBE would rule. ; 
d. Taxad-forest. 
ı. General. ne 
- The forest, here "<önsidered; is that in which species of Dash or. 
Podocarpus either dominate or play a conspicuous part. There are two distinct 
‚classes of associations, those of dry and those of semi-swampy ground, but 
not only are they connected by intermediate combinations and floristically very 
similar, but they contain the same growth-forms and can hardly be considered 
ecologically distinct. All the same, the difference in habitat makes itself 
strongly felt, insomuch that the forest of the dryer ground is a mixed community 
is pure so far as tall trees are concerned. 
Taxad-forest occurs throughout the North, South and, Stewart: dolle 
steppe-climate forbade, nor is it restricted to the lowlands. A 
Ifthe species almost confined to other forkst-associaign besklitted to < 
with those of great rarity, but counting those restricted to. m 
district, or portion of such, then the. ‚total number of species 
taxad-forest of New ge is eg 300, er which 72 are 
