364 A HANDBOOK OF CONIFERS 



dealing with these moths. The Pine Looper Moth {Bupalus pini- 

 arius, Linnaeus), the Pine Moth {Gastropacha pini, Ochsch), the 

 Black Arches Moth {Limantria monacha, Linnaeus, and the Pine 

 Sphinx Moth {Sphinx pinasiri, Linnaeus), sometimes cause con- 

 siderable injury in this or other countries by feeding upon the 

 leaves. Pine Aphides {Chermes spp.) are often present upon Wey- 

 mouth, Scots, and other pines. They are distmguished by the 

 white, woolly protective covering, and stems, leaves, and cones 

 are sometimes white with insects. They are capable of causing 

 considerable injury, and they should be kept in check by spraying 

 infested trees with a paraffin wash and by seeing that all trees are 

 perfectly clean before leaving the nursery. Cut timber may be 

 attacked by Giant and Blue Wood Wasps {Sirex gigas, Linnaeus, 

 and S. juvencus, Linnaeus). The wasps should be destroyed 

 whenever possible, for their larvae sometimes ruin timber during 

 the seasoning process. 



Fungi such as Rhizina inflata, Quelet, Trametes radiciperda, 

 Hartig, and Armillaria mellea, Vahl, sometimes kill many trees 

 by attacking the roots and the portion of stem immediately above 

 the roots. Trees planted too deeply are very susceptible to 

 attack. Attention to drainage and shallow planting are safe- 

 guards against attack, but where stumps and roots of old trees are 

 present in newly planted ground there is always danger. Should 

 an area of woodland be attacked, the infected trees should be dug 

 up and burnt, and a deep trench be dug around the area to prevent 

 the spread of the fungus to the roots of other trees. Fruiting 

 bodies of the fungi should be collected and burnt. Weymouth 

 Pine Rust {Cronartium ribicolum, Dietrich), is often disastrous 

 to Weymouth and other " five-leaved " pines. It is conspicuous 

 on the bark in the form of greyish bodies enclosing orange-coloured 

 spores. These spores pass on to the leaves of Black Currant 

 Bushes, where another stage in the life-history is passed, the spores 

 of this stage passing again to the pine. Affected pines should 

 be burnt and black currant bushes should be removed from the 

 neighbourhood of plantations. Pine wood is very susceptible 

 to attacks by the Dry Rot Fungus {Merulius lacrymans, Fries), 

 and any wood in contact with the earth, or used in places where 

 there is not a free circulation of air, should be protected with 

 creosote or some other suitable preservative. Dote or bluing is 

 a condition often noticeable in pine timber. The wood, parti- 

 cularly the sapwood, is more or less deeply stained by blue marks. 

 This indicates the first stage of decay, the discoloration being 

 due to fungus agency. Careful attention to seasoning usually 

 prevents loss from this cause. 



