462 The Plague of Field Mice, by Sir Walter Elliot. 



One experienced agriculturist was of opinion that, on the 

 10,000 acres of the Borthwick water pasture which had been 

 wasted to a greater or less degree, the damage could not be 

 taken at less than £5,000. 



The foregoing statements refer only to the mischief done by 

 voles in grazing grounds, but they have been found even more 

 destructive in woodlands, the most familiar instance of which is 

 that before referred to and described by Mr Jesse, as having oc- 

 curred in certain new plantations made by the Department of 

 Woods and Forests, in the Crown Lands of the New Forest, 

 Hants, and Dean Forest, Gloucestershire, in the year 1814. 



Shortly after they were formed, vast numbers of five-year-old 

 oaks and chestnuts were eaten through, close to the ground, by 

 field-mice. They appear to have had a predilection for hollies, 

 climbing up to a height of 5 or 6 feet, and stripping the branches 

 after they had barked the stem. It was on this occasion that 

 the plan of destroying them by means of holes dug in the 

 ground was first tried with success. During the three or four 

 months that the visitation lasted, it was estimated that upwards 

 of 200,000 mice were destroyed, aided by the attacks of their 

 natural enemies, and by starvation, which forced them latterly to 

 prey on each other. * 



About 1825, the oak coppices on the estate of Cameron, in 

 Dumbartonshire, were attacked, without apparent cause, and the 

 depredators were discovered by the successful adoption of the 

 above expedient, which entrapped them in numbers.! 



The case of the Duke of Buccleuch's woods at Drumlanrig was 

 brought before the British Association, at the Dundee meeting, 

 in 1867, by Dr Grierson, who had noticed the mischief to be 

 annually increasing since 1852. The trees chiefly attacked 

 were the oak and ash, the holly being a special object of attrac- 

 tion, but they spared the pines and the mountain ash. This 

 continued till the trees were twelve years old, when they were 

 generally safe.j Dr Grierson had observed the same thing 

 several years before on the estate of Maxwellton, in Glencairn 

 parish. 



* Gleanings in Natural History, i, 166. 



t M.S. 



% Report of Brit. Asso. for 1867, pt. ii., p. 82. 



