92 FORESTRY 



Prevention : Spraying with Bordeaux Mixture, consisting 

 of sulphate of copper, lime, and water. 1 



SEEDLING FUNGUS, Phytophthora omnivora, is the cause of 

 "damping off" in seedlings in the cotyledon (seed-leaf) 

 stage. Beech is particularly subject to the pest, but Maples 

 and conifers also may be attacked. The cotyledons become 

 black, and die. Wet weather and close situations favour the 

 disease. Spores of this fungus lying in the soil, have the 

 faculty of maintaining their germinative power for a number 

 of years. It is therefore advisable to refrain for a time 

 from using polluted nursery ground for seed-beds, and rather 

 utilise it for transplants, which will not be endangered. 



VARIOUS POLYPORUS SPECIES. Polyporus vaporarius is de- 

 structive to Spruce and Scots Pine, converting the wood of 

 these trees into a mass of brown dust. 



The common P. sulphureus, which gains entrance by a 

 wound, attacks the timber of Oaks, Poplars, Willows, and 

 other broad-leaved trees, causing the timber to turn brown 

 and dry. 



P. dryadeus and P. igniartus are parasitic upon Oak and 

 other hard woods. 



OAK-ROOT FUNGUS, Roselltnla quercina. During damp 

 weather, in July and August, this fungus is apt to spread very 

 rapidly from root to root among plants in close contact with 

 each other. The roots of one- and two-years-old seedling 

 Oaks are those which suffer. When from no apparent cause 

 young Oaks in seed-beds have a faded appearance, with the 

 leaves pale and sickly, this fungus should be suspected and 

 investigation made, for it is very contagious. Close inspection 

 reveals small black pustules upon the tap-roots of attacked 

 plants. Prevention of further damage consists in the prompt 

 removal of those infected. 



CANKER FUNGUS, Nectria ditissima. Though of so frequent 

 occurrence upon the Beech that it has been called "beech 



1 To twenty-two gallons of soft water add four pounds of copper 

 sulphate and eight pounds freshly slaked lime, and apply with a Knapsack 

 sprayer. Tr. 



