EXERCISE 38 

 FACTORS AFFECTING THE GERMINATION -OF SEEDS 



Object. To study the factors affecting the germination 

 of seeds. 



Explanation. In order that a seed may grow it must be 

 supplied with the proper amount of moisture, air, and heat. 

 It is well known that seeds will not germinate if planted 

 when the soil is too cold. The proper temperature for 

 seeds to grow varies with the seed of different plants. Some 

 seed, like oats and clover, will germinate when the soil is very 

 cool, while other seeds, like pumpkin and tomato, require 

 much higher temperatures for germinating. A temperature 

 of 70 to 80 F. is sufficiently high to germinate the seeds 

 of most farm crops. 



Seeds will not germinate unless supplied with moisture 

 in proper amounts. If the soil is too dry, the seeds will not 

 germinate, while if it is too wet, the soil is often too cool for 

 germination to take place. Oxygen or air is also necessary 

 for germination. Seeds will not germinate well when the 

 soil is badly crusted because they do not receive sufficient 

 air. 



Equipment. 1. Six washpans. 



2. A stick with blunt end for compacting the soil. 



3. Two soils, sand and clay. 



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