44 THE SCOTTISH NATURALIST 
total effect. The war area demanded wood; in view of 
the stoppage of timber imports, home industries, and 
especially the coal-fields, demanded wood; and consequently 
great forest areas were cleared of timber. But this was 
only part of the influence, for in normal times wood 
may be felled without very serious disturbance of the 
insect fauna. During the war, however, lack of labour 
made it necessary that the branches and stumps of felled 
timber should lie long on the cleared patch, and this was 
the culminating factor in creating conditions unusually 
favourable to the increase of harmful forest insects. 
Dr Munro’s thorough method of inspection may afford 
useful hints to the collector. “The felled area was first 
traversed, and a general idea obtained of the age and 
conditions of the stumps and slash (branches and twigs) 
as affording breeding-ground for insects. At the same 
time, flying or crawling adult insects were collected. A 
number of stumps throughout the area were then examined. 
The roots were bared of soil, and the bark prised off from 
the stumps and roots. By this means the bark-dwelling 
insects and their eggs and larve were exposed. When 
no adults were present, such insects as the Pine-weevils 
and Longicorn Beetles were identified by their larve 
and the Bark-beetles by the nature of their egg galleries. 
The slash was also barked and examined, and the insects 
identified in the same manner. The abundance or scarcity 
of each insect, the stage of its life-history, and its habitat 
were noted.” 
This close survey brought to light many facts of interest. 
Throughout the Scottish areas examined there was unusual 
prevalence of the Large Pine-weevil, Ay/obzus abietes, and 
of the Black Pine-beetle, Hy/astes ater, and often also of 
the Pine-shoot Beetle, Myelophilus piniperda. Such was 
found to be the case in several areas of Peeblesshire, 
Perthshire, Forfarshire, Aberdeenshire, Morayshire, and 
Inverness-shire, and detailed examination showed a close 
connection between felling operations and the increase 
Of ‘the tinsects. Wo take a icleatycase: In Perthshire at 
Dunkeld, on the Atholl Estates, several hundred acres of 
