132 CHABACTEBISTICS OF AN AUXILIARY SPECIES. 



level with, much less to overtop, the principal species. 



2. A hardy constitution. Young individuals of the auxiliary 

 species should be able to stand a certain appreciable degree of 

 exposure. 



3. Longevity not inferior to the rotation applicable to the princi- 

 pal species. This is the best guarantee for the successful natural 

 reproduction of the auxiliary species, for the presence of a sufficient 

 number of seed-bearing individuals of it, when the crop comes 

 under regeneration just before being felled, is thereby assured. 



4. Ability to shoot up again readily after repeated cutting back or 

 topping off. Many an individual of the principal species has to be 

 saved from suppression by faster growing individuals of the auxi- 

 liary class, and this can be done only by keeping these latter down, 

 for a time at least, by cutting them back or topping them, as the 

 case may require, once or more frequently. 



5. Persistence of foliage during as many months of the year as 

 possible, combined, of course, with a lower stature (Essential Condi- 

 tion 6), and slower rate of upward growth (Useful and Desirable 

 Character 1). This will add to the effectiveness of the auxiliary 

 species both as a soil-improver and as a nurse for any advance 

 growth that may come up. 



6. Accommodating nature as regards soil and situation. The 

 possession of this quality must materially facilitate the culture of 

 the auxiliary species in the general interests of the entire crop. 



