376 SYLVICULTURAL NOTES ON TIMBER TREES 



Alder, Birch, Ash, and Hornbeam suffer less from transplant- 

 ing than almost any other valuable timber trees, and grow 

 more rapidly from the start. 



If desired, Sycamore and Norway Maple may be cut over 

 at the ground level, at the time of planting ; though it would 

 be better to wait for one year. But usually there is no need 

 to cut the trees over, as their natural growth is vigorous and 

 straight. 



Rotation. This should be about 90 to 100 years. 



Of Fungi. Rhytisma acerinum causes the familiar black 

 blotches on the leaves, but little harm is done thereby. 



Phytophthora omnivera sometimes causes " damping off" 

 in the young seedlings. 



Nectria cinnabarina (showing reddish pustules on the 

 bark of fairly young wood, when dead) often causes great 

 damage to the living trees. 



Various species of Polyporus (the Bracket Fungi) attack 

 the stems through wounded surfaces. 



Of Insects. Cockchafer grubs gnaw through the roots 

 of seedlings and young trees. 



The Field Maple is of little sylvicultural importance. It 

 is a native tree, and grows wild amongst coppice and in 

 hedgerows. 



It never grows to any great size, and, except as inferior 

 coppice growth, should be regarded as a weed. 



