156 OUR FORESTS AND WOODLANDS 



is obtained about the age of seventy or eighty 

 years. On the most favourable classes of soil 

 it will often pay well only to fell it at eighty or 

 a hundred years, but in less favourable situations 

 it may have to be harvested at about sixty years 

 of age to escape the danger of becoming black 

 in the heart and unsound in consequence of a 

 fungous disease caused by Nectria ditissima. Par- 

 ticularly common in soils of a very limy nature 

 this disease soon works its way up from the butt 

 into the top of the bole and the main branches, 

 and renders the tree unfit for timber. Where 

 prevalent the disease often attacks the ash while 

 still in the earlier stages of growth, and pro- 

 mising young plantations are sometimes very 

 speedily and completely ruined from this cause. 

 Seedlings also suffer, on soils unsuited for ash, 

 from another fungous disease due to Phytophthora 

 omnivora, which also often attacks beech seedlings 

 at the time of their germination. 



Wherever seed-bearers are in the immediate 

 neighbourhood, ash comes up freely on most 

 kinds of soil. 'Ash cometh up everie where 

 of it selfe, and with everie kind of wood/ Holin- 

 shed truly remarks. In some of the beechwoods 



