CONIFEROUS FOREST TREES IN GREAT BRITAIN. 63 



places either by this method or probably more certainly by 

 the strip method, i.e. the successive felling of narrow strips, 

 provided protection was afforded against sheep, deer, rabbits, etc. 



It is often stated, both in text-books and elsewhere, that 

 Scots pine will grow under almost any conditions. It is true 

 that it will exist on a wide range of soils, elevations, 

 and exposures. The conditions, however, under which Scots 

 pine will give a reasonable mean annual increment per acre 

 of timber are strictly limited. It must always be remembered 

 that it is this mean annual increment of timber, together with 

 the money value of such timber, that determines whether 

 any particular area can be economically afforested or not. 

 Beyond a doubt many of our fairly well-stocked woods of 

 Scots pine have not given and are not giving an economic 

 increment. In forestry, as in other industries, the call must 

 be for greater production. It is the only way to establish 

 the industry on an economic basis, having regard to the 

 greatly increased cost of forming and tending plantations. 

 The increment can undoubtedly be increased by better manage- 

 ment, but in many cases it will be necessary to seek for some 

 more productive species for conditions which previous forestry 

 experience has considered suitable for Scots pine. 



Scots pine attains its fullest development on fairly well- 

 watered sandy soils, at comparatively low elevations, in 

 sheltered positions. It does not require too fertile a soil, 

 and is comparatively immune from late frosts. It rarely 

 gives satisfactory results on peat of any depth. In the 

 past Scots pine has often been used as a shelter tree at the 

 upper limits of plantations and on exposed knolls. From a 

 production point of view, it is rarely satisfactory in such 

 situations, but it is improving the soil conditions and is 

 thus preparing for more productive species. 



Unfortunately, Scots pine has many natural enemies which 

 are not only numerous but also widely distributed. The roots 

 of the newly-cut stumps of this species are the breeding-places 

 of the pine weevil (Hylobius abietis), and this weevil then sallies 

 forth and does most serious damage to young plantations, 

 not only of Scots pine but of practically all conifers. In some 

 cases, especially when allied with other species of beetles, 

 eg. species of Hylastes, and with drought, this enemy is 

 responsible for the complete destruction of young plantations. 



