144 NEW ZEALAND PLANTS. 
CHAPTER X. 
THE EVOLUTION OF A NEW FLORA AND VEGETATION. 
General remarks — Number of foreign plants growing wild in New Zealand— 
Origin of the plant aliens—Statistics regarding the families, genera, and 
species of the invaders — The comparative rareness of most introduced 
plants—No foreign plants in the primitive plant-formations—Classification 
of plant-associations at the present time—Names for the different classes of 
associations, and their definition—Subdivisions of the induced associations 
—Some modified associations—Modified grassland—Modified dune-hollows— 
Modified salt-meadow—Modified forest—Indigenous induced associations— 
Danthonia grassland—The depleted grassland of Central Otago—Rejuvena- 
tion of subalpine scrub—History of commercial phormium swamp—Other 
indigenous induced associations — Adventitious associations — Tree, shrub, 
herb, and water associations — Hakea on the gumlands — Origin of a gum- 
tree association—The foxglove spreading—Distribution according to habitat 
—Something about weeds. 
Ir the floras of Europe and temperate Asia be considered, where 
through century after century the influence of man has reacted on 
the plant-life, it seems clear that in a surprising number of cases it 
is impossible to say with any degree of certainty that such-and-such 
a species is truly indigenous. Take a flora of Great Britain for 
example, open it haphazard, and see what unnatural habitats are 
frequently cited for the species, such as fields and waste places, waste 
places near gardens, meadows and commons, river-banks and osier 
beds, wall-tops, sandy fields, hedge-banks and roadsides, copses, and 
cornfields. But there is no need to multiply instances.’ Evidently 
any attempt to explain how such European floras have attained 
their present proportions must be mainly guesswork. Still more 
difficult must it be to attempt in Britain or similar countries to 
reconstruct the primitive plant-covering such as it was before man 
had taken a hand in its distribution. 
Now, in New Zealand the state of affairs is quite different. If 
an indigenous plant is found in a hedgerow, a meadow, or a 
waste place, every one knows it is growing in a situation into which 
it has been driven by the influence of man. It is also known, 
with only three or four exceptions at most, what species are truly 
indigenous, and so, too, what vegetation is really primeval. 
