82 FORESTRY 



is effective in preventing the larvae which have hibernated in 

 the soil from again reaching the tree-tops. A special and 

 inexpensive " caterpillar-lime " is the preparation now com- 

 monly used ; it remains semi-liquid much longer than ordinary 

 tar. The bark, at about breast height up the stem, is made 

 smoother by rapidly scraping off the rough outside scales 

 from a band about two inches broad, and this it is which is 

 afterwards painted with the glutinous substance. 



PALE TUSSOCK MOTH, DasycMra (Orgyia) pudibunda. In 

 early summer (May and June) eggs are laid in clusters low 

 down on the stems of Beech, and from thence the larvae 

 crawl to the crowns of the trees, where they feed upon the 

 leaves. They descend from the trees in autumn, and pupate 

 in the fallen material on the ground. The protective mea- 

 sure by means of bands of viscous tar, suggested for the 

 eradication of the Pine Moth, is also applicable for this 

 insect. The bands, of course, must be made before the 

 eggs are hatched, and at a height (about nine feet) that will 

 ensure most of the larvae being caught. 



Remedial treatment in this way is rendered fairly easy 

 owing to the pest being generally confined to older woods, 

 but it is not always necessary. 



BLACK ARCHES or NUN MOTH, Liparis monacha. The ova 

 are deposited in small clusters between fissures in the bark, 

 and there they lie over winter. The young caterpillars, on 

 emerging in April or May, begin by feeding upon the under- 

 most twigs, but the attack generally ends by leaving conifers 

 practically destitute of needles. In feeding, the caterpillars 

 waste as much as they devour ; they bite needles through 

 about the middle, and eat only the short stump ; leaves are 

 nibbled only at the stalk and midrib, the rest falling to the 

 ground. 



Pupation takes place in a cocoon loosely attached to the 

 stem, or about the lower branches, or upon underwood. 



Few forest insects have caused so great destruction as the 

 Nun Moth ; Spruce and Scots Pine suffer very severely, 

 while Beech, Oak, and Birch do not entirely escape. 



