326 BRITISH FOREST TREES 



aspen during the processes of weeding and clearing, or at 

 latest during the early thinnings. The saugh is content with 

 a much drier soil than any of the other kinds, and is even 

 to be found on all classes of soil suitable for the beech. Hut, 

 like the aspen, it can hardly be retained, even if desirable 

 from a sylvicultural point of view, for longer than thirty to 

 forty years in mixed forests, owing to its liability to suffer 

 from red-rot. 



The other tree species, the crack, white and Bedford 

 willows, are not generally cultivated in osier-beds, owing to the 

 lesser flexibility and toughness of the withes they yield ; but 

 they find their chief uses as ornamental trees for parks and 

 damp spots on the fringe of forests, or as pollards on 

 meadows and by the edge of streams. Pollarding is 

 adopted wherever the sylvicultural utilisation of the soil is 

 secondary to its use as pasture-land, or where inundations 

 are frequent, or the land is usually under water for some 

 time during the period of active vegetation. The lopping 

 usually takes place at from six to ten feet above the ground, 

 being regulated by the extent to which the ground may be 

 overshadowed, which also of course determines the distances 

 at which the trees shall be originally planted. Where 

 pasturage is desired, they should not stand closer than six- 

 teen to twenty feet, but where pollarding takes place mainly 

 on account of the liability of the situation to be inundated 

 in late spring and summer, the distances chosen are 

 generally from ten to thirteen feet apart. For the first few 

 years after the plants have been put out, the stems get 

 covered with twigs from the adventitious buds, but these 

 shoots must be regularly removed, so as to stimulate and 

 strengthen the reproductive power of the poll. The 

 harvesting of the poll-shoots takes place during the third 

 or fourth year, and after that the finer withes may be re- 

 moved annually, whilst the total clearance is carried out every 



