86 



OUTLINE OF CROP MANAGEMENT 



are grown for the special purpose of being turned under, root and top, and are not usually a definite 

 part of the rotation ; but, so far as it goes, the root-and-stubble part of similar crops employed in 



the rotation answers the same purpose. 



(6) Well-considered rotation schemes reduce the 

 necessity of excessive use of concentrated or chemi- 

 cal fertilizers. On the other hand, they may utilize 

 such fertilizers to greater advantage than do the con- 

 tinuous-cropping schemes, as has been shown by the 

 Ohio Experiment Station. 



(7) A good rotation provides for the making of 

 farm manures, because it grows crops for the feed- 

 ing of live-stock. As a general practice, it is better 

 to market the hay and straw crops in the form of ani- 



Fig. 120. Four-row beet cultivator of today. ^^ig ^j. ^nim^j products than to put them on the mar- 



ket directly ; for the farmer not only has the opportunity to make an extra profit by an extra process, 

 but he gains the manure with which to maintain the fertility of his lands. He raises the crop to feed 

 his stock to secure manure to raise a better crop. In • « the maintaining of fertility, the live- 

 stock farmer has the great advantage of the horticul- 1|) turist or other special farmer, for the 

 latter must resort to special practices or special pur- J^ chases in order to maintain the produ- 

 cing power of his land. 



(8) Rotation is a cleaning process. Cer- 

 tain weeds follow certain crops. Chess and 

 cockle are common weeds in old wheat-lands. 

 The life-cycle of these plants is so similar to 

 that of wheat that they thrive with the 

 wheat; and the seeds may not be removed 

 from wheat-seed in the ordinary cleaning 

 process. These weeds are soon eliminated 

 by the grass-course in the rotation, or by 

 some clean-tillage course. Most weeds are 

 eradicated in the course of a good rotation ; 

 in fact, a rotation cannot be considered to be 

 good unless it holds the weeds in check. With • 

 crops which are not grown as a part of a 

 rotation, as rice, it is sometimes necessary to 



Fie. 121. stubble digger, to fit land for a succeeding crop, 1906. 



interject another 

 Insects and 

 follow all crops. 

 Nearly all continu- 



crop for a year or two in order to clean the land. 



plant diseases follow certain crops. There are no insects or diseases that 

 Therefore a rotation cleans the fields of many of these troubles and pests, 

 ous-cropping schemes run into these difiiculties sooner or later. A short and 

 sharp rotation, for example, is the best means of contending with wire- 

 worms. It is not uncommon sometimes to find onions failing year after 



year in the best onion regions. The 

 trouble is likely to be due to pests or 

 diseases. Two or three years of celery 

 or other crop may clean up the difficulty. 

 The horticulturist is particularly liable 

 to suffer from insects and plant diseases, 

 especially if he is an orchardist, because 

 he cannot well practice a definite rota- 

 tion. The larger part of the spraying 

 devices and materials are devised to meet 

 the necessities of the horticulturist. 



(9) A rotation allows the farmer to 

 meet the needs of the staple markets by 

 providing a continuous and predictable 

 Fig. 122. Modem riding cotton- and corn-planter, output. 



