336 SYLVICULTURAL NOTES ON TIMBER TREES 



ALDER. 



Alnus glutinosa = Common Alder. 

 Alnus incana = The White Alder. 



The Common Alder is a native tree to this country. 



As to Seed. The seed ripens at the end of September, 

 and the germinative capacity is about 25 per cent. One 

 pound of seed contains about 320,000 seeds. 



Trees 25 years old give good crops of seed, and good 

 seed years occur every 2 or 3 years. 



The timber is soft and splits easily, and is of a reddish- 

 brown colour. It lasts for a long time under water, but 

 otherwise soon decays. 



If logs are not converted at once, they must be barked, 

 or strips of bark must be taken off, so as to help it to dry ; 

 otherwise, it very quickly deteriorates. 



Soil and Situation. A moist soil is essential. It will 

 grow in the wettest of soils, provided there be no stagnant 

 water. It is very sensitive to drought. A moderately deep 

 soil is necessary. It is fairly hardy as to late frosts. 



Cultivation, etc. It is a light-demanding tree ; but will 

 bear considerable shade when young or when coppiced, pro- 

 vided the soil be sufficiently moist. It is an excellent tree 

 for coppice on very wet soils. It grows very rapidly from 

 the stool and lends itself to a long rotation as underwood, 

 coppice poles 25 years old often being 40 feet high, and 

 very straight and clean. The stools are long-lived. 



Short rotations are harmful to it. 



It is not a very profitable tree to grow by itself; and the 

 market for its timber is not very good in most localities. 

 It is most useful as coppice under Poplars, Willow, Ash, 

 or Oak. 



The White Alder grows well on the same kind of soil as 

 the Common Alder. But it will also thrive on very dry soil ; 

 and it can bear a considerable amount of shade. It is very 

 quick growing when young. It has stoloniferous roots, and 

 throws out innumerable suckers. 



