152 



ELEMENTS OF AGRICULTURE 



141. General Farming and Special Farming. — Od 



many farms are produced each year several different 

 kinds of crops; snch as wheat, corn, tobacco, and oats. 

 This practice is called general farming. But gradu- 

 ally the production of one main crop on each farm is 

 becoming customary. In addition to such crops as are 

 needed to feed themselves and their stock, many plank 

 ers raise for the market only one main crop, as for ex- 

 ample, cotton, rice, or tobacco. This is called special 

 farming. The kind- of crops the farmer raises is usually 

 determined by his soil and climate, and by the demands 

 of the market. 



142. Selecting Seed. — After determining on the 

 kind of crop to be planted, and after preparing the 

 soil in which to plant it, the next important step is 

 selecting the seed; and in doing this it is important 

 to remember that poor seed produce poor crops. Select 

 only good, pure seed for planting. Seed are unfit for 

 planting: (1) When they come from diseased or ill- 

 shaped plants, (2) when they are not fully matured, 

 (3) when they are too old, (4) when they have been 

 attacked by disease or insects, (5) when they are small 

 and ill-shaped, (6) when they are mixed with other 

 seed or trash. 



143. How to Test the Purity of Seed.— The first 

 thing to do is to weigh the seed. The seed of different 

 crops vary in weight, and the weights per bushel for 

 pure seed have been determined for most farm crops. 

 These standard weights are given in a table in the 

 appendix. If the sample of seed to be tested does not 

 agree in weight with the standard, then it is reason- 



