FUNGUS DISEASES. 



23*7 



I. Chief Fungus Diseases in Nurseries and young Natural Regenera- 

 tions. 



* The Beech-seedling fungus, Phytophthora omnivora, chiefly attacks 

 Beech-seedlings, the stalks becoming brown, the roots black, and the 

 cotyledons and primary leaves spotted with brown before they wither, 

 die, and rot quickly during rainy weather. In about a week from the 

 first signs of the disease its full effect is noticeable if May and June are 

 wet, while in dry seasons it takes longer for seedlings to assume the 

 characteristic scorched, blackened appearance. During warm, damp, 

 spring weather it may do great damage in Beech natural regenerations, as 

 well as in nurseries. Besides being wind-borne, the spores are conveyed 

 on men's boots and clothing, and by animals of all kinds. Next to Beech, 

 it chiefly attacks Ash, Maple, and Sycamore, but also all other seedlings 

 when once epidemic, and whole Conifer seed-beds may be destroyed 

 before the seedlings even appear above ground. Resting-spores may lie 

 dormant for years till finding favourable conditions for germination, and 



