BRITISH FOREST TRM - 231 



species, and growing on soils not particularly well suited to 

 their normal requirements, seldom show anything like close 

 canopy, but consist of sparse patches often of indifferent 

 development; where, however, the soil is good, and the 

 moisture not excessive, they occasionally show very fair 

 development, and include also good specimens of the ash. 

 In other localities, whenever the water-level has slowly sunk 

 from one reason or another, the spruce often also finds its way 

 into the alder groves spontaneously, and shows a develop- 

 ment more or less generally proportional to the degree of 

 moisture contained in the soil. The alder is usually the 

 more forward in growth, and stimulates the spruce to rapid 

 development in height, and where the latter occurs in 

 scattered individuals only, this is sufficient to improve the 

 shape of the bole of the former. Where the spruce is not 

 self-sown, but is introduced artificially, the admixture takes 

 place most advantageously after the alder poles have thinned 

 themselves freely. 



The fall of timber in alder coppices is usually accom- 

 plished during hard frost, as the harvesting of the crop is 

 much easier then than at other times ; but felling and 

 extraction must then take place almost simultaneously. 

 Where such difficulties do not exist as to extraction, the 

 fellings can preferably be made either in late autumn or 

 in spring, as, there being then less danger of the stools 

 chipping, the fall can be made low down close above the 

 ground ; where inundations are to be feared in spring, 

 higher stools must be left, otherwise the shoots run the risk 

 of being suppressed by rank grass and weeds. In many 

 alder woods raised mounds are necessary as paths here and 

 there ; without these, sylvicultural operations could some- 

 times hardly be carried out or superintended properly. 



The Formation of Alder M'oods by sowing is occasionally 

 accompanied with greater difficulties than arc usual with 



