140 THE PRINCIPLES OF 



never becomes very foul, and never is absolutely clean. 

 While the system of catch-cropping is a bar to perfect clean- 

 ness, it is likewise a preventative to weeds thriving extrava- 

 gantly, because the ground is always under tilth, under 

 cultivation. Fodder crops may be grown on stiff land as 

 well as on light land, in the north as well as the south ; 

 but where we have these conditions we must make up 

 our minds either for fodder or for roots. We must either 

 grow fodder crop and relinquish root crop, or choose the 

 root crop and relinquish the fodder crop; we cannot do 

 both. 



Now I trust I have in some measure, at all events, fulfilled 

 what I hoped to do, and given a bird's-eye or general view 

 of the cultivation of these various kinds of crops; and in 

 the last place, I would confide to the teachers of this subject 

 the syllabus which I employ myself in the teaching of, not 

 only the cultivation of crops, but of all other matters con- 

 nected with crops. It is extensive, and requires a large 

 amount of knowledge, especially when it is applied to each 

 crop separately. 



The syllabus of crop cultivation begins with the botanical 

 position I mean the botanical position of grasses, wheat, 

 clovers, cabbages, turnips, and any other crop. The botanical 

 position of the root crops, for example, is a point which an 

 agricultural student should not be ignorant of. 



The history of the crop is the second point of the syllabus. 

 It is astonishing how many of our crops have a distinct 

 history ; we know when they were introduced and who intro- 

 duced them. Two hundred years ago we had very few 

 cultivated plants at all. Their introduction forms a very 

 instructive page of history, and must always be an excellent 

 illustration of the value of observation and of science. The 

 history of cultivated plants as well as the history of the 

 improvement of animals are grand chapters in the national 



