GENEBiX PEEPAEATION OF THE SOIE. 167 



inches deep and 2 feet wide, along the boundary and throwing up 

 the earth along its inside edge (Fig. 12). The sections of both- 

 mound and ditch should he an equal-sided trapezium, and would 

 necessarily be equal in area. A herm or scarcement, AB, should be 

 left between the mound and ditch to prevent the earth from slipping 

 back into the latter. The mound should be thoroughly well rammed 

 before the fence is put up. The combination of mound and 

 ditch not only reduces the height of the wire fence required, but 

 the ditch, besides serving as an additional protection, also performs 

 the office of a drain. When the nursery is situated on a pro- 

 nounced slope, the ditch and mound cannot obviously be employed, 

 since they would only facihtate the erosion of the soil. On such 

 slopes no special protection wiU be required along the lower 

 edge of the nursery, since the retaining wall of the lowest terrace- 

 (see Article 5, page 169) would be as good as a sunk fence. 



All tight-bound fences of wooden posts and wattling are entire- 

 ly out of place at elevations under 5000-6000 feet, where 

 ■white ants and destructive weather influences would necessitate- 

 their constant renewal. Moreover they would be no barrier to> 

 pigs, porcupines and hares. 



Live hedges, of species varying with the forest region, may be 

 employed when the area of the nursery is very large and is partly 

 ■used for other purposes, as, forinstance, an orchard or experimentat" 

 forest garden. But, in any case, a more effective internal fence 

 would be required for the portion of the area devoted to real nursery 

 work. Live fences have, for the most part this prohibitive dis- 

 advantage that tbey harbour noxious vermin, besides, when not 

 thorny, giving free access to hares, &c. The principal species best 

 adapted for Hve fences are — ^in the Himalayas,. Crataegus, Pyrus 

 Pashia, roses, &c. ; in the plains, the prickly pear, species of 

 Euphorbia, Zizyphus, Carissa, Ccesalpinia, Capparis horrida, ^c. 



The only way to keep out elephants is to surround the nursery 

 "with a ditch about 10 feet wide and at least 8 feet deep, and with 

 sides making an angle of not less than 60° with the horizontaL 

 As an extra precaution the bottom of the ditch may be studded 

 ■with sharp stakes* 



ARTICLE 5. 



General Prbpabati&n of the Soil. 



Pirst Cultivation, 



The first thing of all to do is to clear the ground of every tree 

 and shrub ; and here we may, therefore, describe in a brief majx- 



