ANNUAL FALLS. 121 



ally desirable that the series of Annual Falls should succeed 

 each other in the direction opposite to that of the most 

 dangerous prevailing winds. Usually in Britain, and especi- 

 ally along the west coast, the S.W., W., and N.W. winds are 

 by far the most dangerous; and the best protection can in 

 these cases be given by making the Annual Falls succeed each 

 other in the direction from KE. to S.W., E. to W., and S.E. to 

 N.W. respectively (see Fig. 30) ; but the trend of the winds 

 often becomes much altered by the run of the valleys and the 

 configuration of the country, and it often happens that very 

 destructive gales come from a different direction to that of the 

 prevailing strong winds. Making the Annual Falls run against 

 wind also protects the soil. This measure is especially necessary 

 with evergreen Conifers, and most of all for the heavily-foliaged, 

 shallow-rooting Spruce ; but it is also best for broad-leaved trees, 

 as it favours natural regeneration, though not in the case of 

 Conifers, whose cones open and shed their seed chiefly during 

 dry E. winds in spring. But it is not necessary that the annual 

 falls should form a contiguous series ; in fact, keeping each two 

 successive falls apart is desirable, especially in Conifer crops, on 

 account of insects, fire, &c., the chief point to be kept in view 

 being that the various annual falls, taken as a series, should be 

 made in the direction against the most dangerous wind. And 

 where large annual falls Ijiave to be made, it is best in Conifer 

 woods to make several small falls in different parts of the woods, 

 instead of one large fall, and to arrange that any two successive 

 falls within the same compartment should take place, if practic- 

 able, only at intervals of 4 or 5 years, in order to prevent 

 damage by Pine weevils. Supposing the compartments are 

 each 40 acres, and the annual fall 20 acres, then it would Be 

 better, with a rotation 'of 80 years, to have 4 age-classes in 

 each compartment, and to spread the annual fall over 2 com- 

 partments, than to have only 2 age-classes and cut one-half of 

 a compartment at each annual fall. 



