l8] PLANT ADJUSTMENTS AND APPLICATIONS 573 



the greatest possible care, and preferably from authenticated speci- 

 mens in view of the frequency with which literature citations, recol- 

 lections, previous identifications, and so forth are prone to err. In 

 this, again, all determinations should be checked. 



Allied studies of, for example, the dispersal methods of particular 

 species, or the distribution of the more complicated communities 

 which they make up collectively, usually involve ad hoc field investiga- 

 tions. Of such studies more and more are needed. In most major 

 populated regions there are nowadays herbaria^ with staffs who will 

 aid in determining plant specimens, if necessary by correspondence, 

 provided a specimen labelled with the place, date, and collector's 

 name is submitted. It is when we attempt to study the more 

 complex communities which make up vegetation, that lasting personal 

 contact is virtually essential. Yet such study is both instructive and 

 rewarding, as vegetation affords a fine indication of local conditions. 

 This was demonstrated in the last chapter. 



Further Applicational Possibilities 



Apart from the practices of agriculture and forestry which to a 

 large extent are ecologically based, conservation of natural resources 

 such as forests and grasslands probably constitutes the most important 

 application of ecology, which itself is to a considerable degree plant- 

 geographical in basis. Modern wildlife and fisheries management 

 should, however, not be forgotten in this connection. Consequently 

 the preservation of natural areas for ecological and allied study is 

 important, and also has its significance for plant geography. With 

 the current disturbance of so many tracts, frequently so drastically 

 that indigenous plant indicators disappear and there may be scarcely 

 any native plants left, it is often only through the ecological or 

 phytogeographical study of ' preserved ' areas that the most appro- 

 priate schemes of land-utilization and conservation can be worked 

 out and applied. Such areas are, moreover, the ' controls ' by 

 which the effects of Man's modification of surrounding tracts can 

 be properly judged. For, to quote Sir Arthur G. Tansley (in R. S. 

 Adamson's The Vegetation of South Africa, 1938), ' A knowledge of 

 what nature produces when she is left to herself is one of the indis- 

 pensable requisites of wise exploitation.' 



^ These are listed, usually with details of staff, etc., for all portions of the world 

 in the Index Herbariorum published periodically by the International Association 

 for Plant Taxonomy, Utrecht, Holland, and sent free to all members of that 

 Association. 



