THE ART OF THE SECOND GROWTH 



II. Frequency of seed years and time allowed for the entire 

 operations. 



III. Shade-bearing character of youngsters and firmness of 

 parents. 



IV. Existence of a permanent system of transportation. 



V. Configuration. 



VI. Danger from storm, sleet, fire, animals, etc., locally existing. 



VII. Size of timber, value of timber, percentage of debris and 

 waste. 



VIII. Marketability of all species or of a few, even of one 

 species only. 



B. According to the manner in -which, the forester 

 selects the nuclei for rcseeding, we distinguish the following 

 types : 



I. Uniform type, or pure shelterwood compartment type, where 

 the nuclei are geometrically and regularly distributed over the 

 entirety of a large area (say over twenty to two hundred acres), 

 the nuclei of the entire area being kept, during the entire progress 

 of regeneration, in or about in the same uniform stage of 

 development. 



II. Shelterwood strip type, where the nuclei proceed, like ad- 

 vancing skirmishers, in regular military order either from the lee- 

 ward side to the windward side of a compartment (cove, slope, etc.),, 

 or else from the North towards the South (Wagner). The nuclei 

 to the leeward viz., northward are kept in a more advanced stage 

 of growth than those to the Avindward viz., southward. 



III. Shelterwood group type, where the nuclei are carefully 

 selected, irrespective of geometrical arrangements, merely on the 

 basis of the fitness of the individual spot to act as a seed-bed. The 

 groups are gradually enlarged, increasing in circumference like 

 waves caused by stones thrown in the water. 



IV. Shelterwood selection type, where the most mature indi- 

 viduals are everywhere in all compartments and continuously se- 

 lected for removal, individually or in small patches, with a view to- 

 the simultaneous reproduction of the species removed by seeds left 

 on such patches. The patch does not form a nucleus to be en- 

 larged; it is to be retained for a long time in its original size. 



In primeval nature, the shelter, or else the soil condition* 



created by a sheltering superstruction for the benefit of the under- 



structure, are secured frequently in connection with a change of 



species. The understruclure requires a fostermother, rather than a 



123 



