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more easily accommodated, such as produce more and easily dispersed seed will conquer 

 the captious ones and those with heavy seed and deep rooting kinds will maintain existence- 

 in regions, where continuous droughts would kill the shallow-rooted ones in their youth ; 

 species that require a long duration of the vegetation period will recede or be over- 

 powered by the quick growing ones ; species of slow growth may be crowded out, when 

 quick growing ones find otherwise favourable conditions. Territories which oflfer favour- 

 able conditions to only one or a few species will present pure forests of one, or nearly one 

 kind only, whilst more diversified conditions will through centuries show a varied appear- 

 ance of forest ; in the end perhaps, however, the shade enduring, longlived, heavy-seeded 

 ones will domineer. In forests, where the shade-loving species, such as beech and spruce, 

 have acquired absolute sovereignty, in consequence of human management (absolute 

 clearing), the light-foliaged and light-seeded kinds will gain ground. In short these ap- 

 pearances and changes are the result of that continuous struggle for existence, which per- 

 vades all nature and is modified in many ways by the hand of man. 



I know that I have only incompletely and in a general way pointed out some of the 

 more important conditions which underlie the growth of our forests. I have done so 

 without any attempt to exhaust the theme in any particular, but have merely endeavoured 

 to draw your attention to the fact, that the whole science of forestry is built, or in the 

 case of this continent, is to be built, upon a very complicated system of elementary know- 

 ledge, which can only be gathered by local observations based on a correct understanding 

 of the physical forces at work. 



Though there are many minor and local influences conditioning forest growth, those 

 discussed in the foregoing remarks may be considered as the principal and determining 

 ones. And without tracing step by step the deductions possible from these for a correct 

 management of forests, we confine ourselves to giving in conclusion, in the form of short 

 theseSjSuch rules of management as result from a logical consideration of the foregoing ex- 

 positions, the observation of which will at least insure a healthful preservation of existing 

 and a successful growth of new plantations. 



1. The principal effort of the forester must be to preserve and increase the " soilbonity"" 

 as defined in the foregoing paper, since upon it depends the productivity of the forest. 



2. The measures to be adopted for this purpose are not much to be sought in direct 

 operations on the soil, but mainly in certain considerations in the selection of species, 

 methods of management, terms of rotation, interlucation, methods of reproduction, and in 

 the general care of the forests. 



3. Only such species should form the predominant part of the forest as are able to 

 preserve the " soilbonity." These are the shade-enduring and the evergreen. 



4. Where an increase of depth, looseness and humidity is especially needed, it is es- 

 sential that such species should be cultivated as, through a plentiful fall of leaves, favour 

 formation of humus, and by the density of their crowns keep out the two enemies of humi- 

 tication : sun and wind. 



5. If for a length of time one species alone is to be cultivated, it must be one with a 

 dense foliage. Light f oliaged ones can only be allowed where Nature has provided in 

 some other way for the conservation of the "soilbonity," because they not only furnish 

 too little material for humification, but impede the latter by giving sun and wind access 

 to the soil, thus drying it up and impoverishing it. 



6. Mixed forests afford greater security against damages by wind, fire, frost, snow, 

 diseases, besides yielding a larger amount of wood. In these the predominant species 

 must be one of the shade-loving or enduring, densely -f oliaged, which protect the soil. The 

 light-needing, thinly foliaged species are only to be mixed in by single individuals, and 

 not in groups, and must be quicker growing or have an advantage in age or height. 



7. Two or more shade enduring kinds can only be mixed, if they are equally quick 

 growing. 



8. In growths which in later years become less dense any underbrush is favourable 

 as protection against sun and wind ; the cultivation of such artificially may be advisable 

 from financial considerations, though it may not be justified. 



9. The distance of the plants in new plantations ought not to be more than three ta 

 four feet, as only thus a sufficient covering of the soil can be efiected. Besides the yield 



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