COMBINATIONS OF STRIP, RIDGE AND TRENCH. 203 



and the resulting seedlings. 



When the ridges occupy the entire interval between two drain- 

 age channels, the top may be expeditiously sown with a drill. 



3. Value and employment of the'methocL 



The method of sowing on ridges is especially adapted where 

 irrigation is available ; also in the several tarais and other swamps 

 in different parts of the country. In nearly every case it is advan- 

 tageous and necessary to flank the ridges with trenches, and when 

 this combination exists, the system is very suitable on dry hill- 

 sides, the trench serving to catch rain water and hold it for the 

 benefit of the young plants on the ridge. By catching a very 

 large proportion of the surface drainage the trenches also serve to 

 diminish the risk of erosion on unstable slopes and on land liable 

 to get ravined. The method is, however, very costly and should 

 be adopted only after the chances of other more economical methods 

 have been fully weighed and considered. 



ARTICLE 8. 

 COMBINATIONS OF STRIP, RIDGE AND TRENCH. 



The following combinations are theoretically possible : (1) ridge 

 with trench or furrow ; (2) strip with trench or furrow ; (3) strip 

 with ridge ; and (4) strip with trench or furrow and ridge. Com- 

 bination (3) can so rarely occur that it will not be described. For 

 convenience of expression, in the rest of this article, the words 

 " or furrow " will not be repeated, and must be understood each 

 time the word " trench " is used. 



1. Combined ridge and trench sowing. 



In studying ridge-sowing we have already had to consider the 

 case of a combined ridge and trench, in which only the ridge was 

 sown. The only difference between that system of ridge sowing 

 and the present method is that here the trench also is sown. It is 

 evident that the trench can in this case never partake of the riatui e 

 of a drain. 



Sometimes both ridge and trench are sown with one and the 

 same kind of seed, so as to secure a double chance of success ; if 

 the sowings on the ridge fail, those in the trench at least are likely 

 to succeed, and vice versa. Such a procedure is of course nearly 

 always a confession of ignorance ; but in this country, for many 

 years to come, all our work must partake to a certain extent of an 

 experimental character, and even when our knowledge of forest 

 conditions in India has been perfected as far as human perfection 



