SVLVICULTURAL LIMITATIONS. 567 



(a) Extent of Possible Advantage of Pannage to Forests. — Belief 

 ill the cultural advantages of pannage requires limitation ; in 

 many cases more harm than good to the forest results ; the 

 standing crop may sufifer by breakage of young growth, or by 

 the mast being eaten in natural regeneration-areas, or by 

 exposure of roots on shallow soil, where the pigs often loiter 

 about. Only in extensive Scotch pine forests, where the herds 

 of swine feed on the pupa3 of the pine-moth and other insects, 

 and destroy quantities of mice, can pannage be considered 

 wholly beneficial. 



All woods, Avhen damage is to be feared, must be closed to 

 pannage. Exceptions are : — the temporary passage of a herd of 

 swine through a wood richly supplied with mast, if they are 

 admitted early in the morning when hungry, feed chiefly on 

 acorns, beech-mast and other fruits, and effect little breakage ; 

 seeding-fellings before any young plants have appeared, but 

 it should then be noted that the partial breaking-up of the soil 

 by the pigs is not nearly so useful as uniform cultivation with 

 the hoe ; also if only a little of the mast is required for 

 natural regeneration, swine may be admitted temporarily in the 

 afternoon, after they have, to some extent, satisfied their hunger. 



Similar precautions (as regards the admission of swine) must 

 be taken in forest compartments reserved for feeding game. 



Ground-mast should be utilized only in parts of a forest where 

 there is a real advantage in having the soil broken-up. This is 

 the case in damp soils, or in places where it is wished to tread 

 in the dead leaves and prevent their being washed or blown 

 away. Pannage is decidedly hurtful when swine are kept 

 throughout the year in a forest either on level giound or on 

 hill-sides, and on poor, shallow or sandy soil which thus becomes 

 still more deteriorated. 



(b) Limitation of numbers of Swine. — Sylviculture demands 

 that only a suitable number of swine should be admitted to 

 a forest, for the herds can be kept under control only as long 

 as there is sufficient mast for their food. If the mast is insuffi- 

 cient, the swine wander over a larger area in order to satisfy 

 their hunger ; they then break into the adjoining closed portions 

 of the forest, and can be kept in hand only with difficulty. 

 It is therefore absolutely necessary to estimate the quantity 



