52 SOILS AND PLANT LIFE 



39. How Nature selects Seeds. — Nature carries on a 

 rigid seed selection. The strong seed produces a strong 

 plant which soon overshadows and crowds out its weaker 

 competitors. The seeds which produce plants that are 

 able to survive the heat and the cold, the drought or the 

 flood, the insect or the disease, are the ones which come to 

 make up the plant life of any locality. 



The farmer destroys the weeds and other enemies 

 which retard the growth of the planted seed. The prob- 

 lem of careful selection and storage of the seed, however, 

 remains. 



40. How Man selects Seeds. — As in the selection 

 of an animal, the selection of any seed should begin with 

 the parent. We want to know that the parent plant is 

 vigorous; that it is of a desirable type; that it is more 

 productive than the average of its kind, bearing fruit or 

 seed of high quality; that it is able to withstand the 

 ravages of insects, the attacks of diseases, and perhaps the 

 extremes of a variable climate; that its root system is 

 strong enough to hold it erect in times of high winds ; and 

 so we might name many other things that man considers 

 in connection with the parent plant whose seeds he wishes 

 to sow in his fields. 



In connection with any given species or variety of 

 plant, there are usually particular characteristics to con- 

 sider in addition to the general ones named above. More- 

 over, it should be understood that just as any given char- 

 acteristic may be regarded as highly desirable, so its 

 opposite, which may be foimd growing in the same field 

 or even beside it in the same hill or row, is just as highly 

 undesirable. 



In the following exercise, you will select from the field 

 stalks of corn which show desirable characteristics and at 



