Displacement and Replacement of Associations and Species: General. 283 
all are occupied by species the greater part of which are rare or absent else- 
E; where. Man, in fact, unconsciously causes the establishment of distinct migratory 
associations. Such waste ground contains about 355 species of which some 
255 are confined thereto. If to these are added some 60 species, that are 
virtually confined to cultivated ground, then it becomes evident that adout 
61 p. c. of the introduced flora plays no part as a displacer or replacer of the 
indigenous vegetation. Nor.is the above estimate high enough, since those of 
the ı02 pasture plants that do not invade the unploughed lands are likewise 
non-militant, in fact probably 102 species are all that extend on to those areas 
where the indigenous vegetation is exposed only to fire, grazing animals and 
the felling or forest or cutting of shrubs. 
Regarding the growth-forms of the introduced plants, — 15 species are 
trees, 26 shrubs, ı5 lianes, 4 parasites, 17 water-plants, 327 herbs, g2 grass-like 
plants and ı7 rush-like plants. Creeping-stems are the most powerful weapon 
in the contest for both introduced and indigenous species as shown in Agro- 
pyron repens, Rumex Acetosella, Cnicus arvensis and Pteridium esculentum. 
| Chapter I. | 
Displacement and Replacement of Associations and Species. 
1. General. 
It is frequently asserted in scientific writings that New Zealand indigenous 
plants are less fitted for their environment than many of the introduced species, 
and, that, in consequence, these latter readily displace and replace the former 
when they come into competition. This is a long way from the actual truth, 
as the previous chapter has partly shown. Wherever any part of New Ze 
land is in its primitive condition and uninterfered with by man or the animals 
he has introduced, none of the exoties have gained a foothold, their great powers 
of dissemination notwithstanding, although the virgin area may be pierc 
all directions by ground occupied by man where there are ü troduced species 
On the other hand, where man has separately, or collectively, bro 
play fire, draining, cultivation and introduced domestic or feral anima 
created a new environment where indigenous and introduced 
latter be present, alike go to the wall and new associations ari 
posely produced, made up,. it may be, purely of exotics, though freque: 
such and native plants. Thus, ikere are two distinct areas, the one do 
by primitive New Zealand conditions and the other by such as apprı 
those of Europe, while between these extremes is a gradual series 0 
mediales. Bea ee N: 
In order to distin; 
FRE e ; | 
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