274 Principles of Plant Culture. 



crooked, and whether the plants are tall or dwarf. Hav- 

 ing decided on the characters that seem to accompany 

 the extreme earliness, we should save seeds only from 

 plants that show all of these characters. After following 

 this kind of selection eight or ten years, we may be able 

 to introduce a new variety of pea. 



It is impossible to so fix variations in plants grown 

 from seed that they will continue to come true without 

 a certain amount of selection, hence varieties propa- 

 gated by seed continually tend to "run out," i. e., to 

 lose their distinctive characters. Seed growers find it 

 necessary to use the utmost care in maintaining their 

 varieties, and the more distinct a variety propagated by 

 seed, the more difficult it is to maintain. 



437. Seed Selection is of Great Importance. From 

 what has been said, it is clear that the cultivator can- 

 not afi'ord to be indifferent as to the quality of the 

 seed he sows. It is not enough that the seed is fresh 

 and plump ; it should be of carefully-bred varieties. In 

 the cabbage and cauliflower, success or failure in the 

 crop will depend largely upon the quality of seed sown, 

 and the same is more or less true in all crops grown 

 from seed. 



438. We Can Induce Variation, in some cases, by 

 special treatment of the parent plants, or by the use of 

 a particular selection of seed. 



a.— By culture. It is generally conceded that culture 

 tends to promote variations that would not have ap- 

 peared in the wild state, in consequence of the changed 

 growth conditions. In improving wild plants, there- 

 fore, we probably have a better chance of securing 



