ROOT CROPS AND TUBERS. 



first formed in plants, namely sugar and starch. The materials 

 that are taken from the soil through the roots, and that which 

 passes in from the air, are worked over in the green leaves, so 

 that while green we would expect to find a considerable quan- 

 tity of mineral or soil material in the leaves. Any green leaves 

 that are cut from the roots when they are pulled, therefore, 

 should be left on the soil where the roots grew, so as to help 

 keep up the richness of the soil. The roots keep on growing 

 during the fall until the weather becomes very cold, therefore 

 they have a good chance 

 to benefit by the nitrates' 

 that are formed during 

 the latter part of summer. 

 They have the advantage 

 of spri ng-so wn grain 

 crops in this regard. 

 Since root crops are such 

 heavy feeders, and since 

 the ground should be 

 kept thoroughly cultivat- 

 ed during their growth, 

 they are generally used 

 as the crop to which the 

 largest quantity of barn- 

 yard manure is applied. 

 In addition to heavy 

 manuring, another very 

 important necessity is 

 thorough cultivation of 

 the soil before the sowing of the seed. The root is thick and 

 compact ; it has to push down and out on all sides. If it can- 

 not go straight down it will twist about or push itself partly out 

 of the ground. For well shapen and perfect roots, then, we 

 must have a well-tilled and well-drained soil. 



Fig. 26. Sugar beet on left grown in good 

 soil, well drained and well cultivated ; beet on 

 right grown in rough soil. 



