THE COMPAKTMENT SYSTEM. ^3l 



shelter- wood which remains after the seeding cutting has been 

 executed. That density must be such as to ensure the most 

 favourable conditions for the further advancement of the 

 3^oung crop ; in other words, it must aft'ord sufficient light to 

 the young crop without exposing it to injury by frost, drought, 

 or excessive weed growth ; at the same time there must be 

 sufficient shelter left to affect the general factors of the locality 

 beneficially. 



It will be easily understood that, apart from the species, 

 the density of the shelter- wood depends on a variety of 

 circumstances, of which the following may be mentioned : — 



i. CuNDITIONS OF THE LOCALITY. 



The shelter-wood should afford protection against the drying 

 up of the soil, frost, cold winds, growth of weeds, and perhaps 

 also against damage by insects. In localities where the young 

 crop is threatened by one or more of these dangers, the 

 shelter-wood must be kept dark; amongst them may be 

 mentioned poor, loose, stony soils, southerly and westerly 

 aspects, steep slopes, localities exposed to dry or cold air 

 currents or to great changes of temperature in spring result- 

 ing in late frosts, those inclined to a strong growth of weeds, 

 especially calcareous soils, where wind falls are apprehended, 

 or where cockchafers and other insects are likely to settle. 

 Where the opposite conditions prevail, in other words on 

 generally favourable localities, the shelter- wood may be less 

 dark, with a comparatively light cover overhead. 



ii. Condition of the Shelter-wood. 

 Old trees have comparatively denser crowns than younger 

 trees. Tall trees give less shade than short ones. Both 

 circumstances must be considered in determining the number 

 of trees to be left for the shelter- wood, so as to produce the 

 desired density. 



iii. Degkee of Prepakation arrived at during the Preparatory Stage. 



The higher that degree, the lighter may be the shelter- wood, 



other conditions being the same. Whenever the preparation 



