26 AGRICULTURE 



seeds. It is best, therefore, to separate the largest seeds 

 from the others by using sieves or screens. 



Testing the germination of seeds. Seeds of some 

 plants lose the power to germinate after they are a year or 

 two old ; others are good when a number of years old. 



If seeds become moist and go through a "heat," they 

 lose their power to germinate. Children can often help 

 their parents by testing the field or 

 garden seeds they expect to plant in 

 order to discover what percentage of 

 them can grow. All that is needed 

 is a plate ; a piece of thick, clean, 

 dark cloth, to be dampened and 

 )Fic. 24. A HOME-MADE spread on the plate ; a similar piece 

 to be dampened and used as a cover 

 for the seeds; and a second plate to place over it all 

 -(Fig. 24). Keep this home-made seed tester in a warm 

 room. Examine the seed on the fifth and eighth days, and 

 .as much oftener as you wish. 



EXERCISE. With a sharp knife, cut through grains of corn that are 

 -soft and dented and through others that are flinty and not dented. 

 Make a drawing to show the difference between the two grains in the 

 ^thickness of the several layers. Select six grains of corn having the 

 largest possible germs, as shown by the size of the depressed area. 

 Select six others with the smallest possible germs. Which grains 

 would you expect to make the largest, strongest young plants and to 

 ! be best able to push up if covered rather deep ? 



Shell ten good ears and measure the shelled corn, so as to calculate 

 how many ears make a bushel (56 lb. of shelled corn) . Write in your 

 notebook the number of ears per bushel. 



A good exercise is to go to a number of cornfields and estimate how 

 jnany bushels per acre each field will yield. If you can get permission, 



