METHODS OP HANDLING GREEN-MANUEE CROPS. 11 



desirable or objectionable and must be taken into consideration in 

 selecting the best crop to grow. 



A green-manure crop should be a legume wherever possible, in 

 order to obtain the addition of nitrogen to the soil. It is also neces- 

 sary that a good growth be made, in order to have a large quantity of 

 organic matter to turn under and incorporate with the soil. Along 

 with good growth should be a heavy development of nodules on the 

 roots, as this is believed to indicate great ability to fix atmospheric 

 nitrogen. 



The quality of being able to stand trampling with a minimum of 

 injury is very important where the crop will be subject to such injury, 

 as is the case in citrus orchards where the picking of fruit takes 

 place while the green-manure crop is yet growing. Uprightness and 

 nontwining stems are also desirable where an ordinary moldboard 

 plow is depended upon for turning under the crop. However, if a 

 disk plow is used or the crop is worked in with an ordinary disk 

 harrow, this does not make so much difference, and where the growth 

 is not allowed to become too rank little difficulty is experienced in 

 plowing it under. 



The texture of the stem should be such as to decompose readily. 

 Practically all crops, however, if turned under at the right stage of 

 growth decay readily. Thus, the question of decomposition is one of 

 turning under the crop at the right time rather than one of selecting 

 a crop that will decay readily. 



That the cost of a green manure may not be too great, it is neces- 

 sary that the price of seed be reasonable as compared with the results 

 to be obtained. 



METHODS OF HANDLING GREEN-MANURE CROPS. 



The methods of handling green-manure crops in California are 

 quite similar throughout the various sections. However, some vari- 

 ation in practice exists among orchardists in the same neighborhood, as 

 well as among those of different localities. 



The following methods are practiced in the citrus and walnut 

 orchards of the southern part of the State, where green manures have 

 been most generally grown. 



PREPARATION OF THE LAND. 



Since clean culture is practiced throughout the year in citrus and 

 walnut orchards except when a green-manure crop is being grown, 

 the land can be prepared at any time for the seeding of such a crop. 



The general practice is to prepare the land for seeding by plowing 

 or disking and harrowing immediately after an irrigation. This puts 

 the land in good condition for the seeding. 



190 



