72 LABORATORY MANUAL OF AGRICULTURE 



Directions. Dig up a number of small rye plants for 

 this study. Be careful not to break the roots in removing 

 the plants from the soil. Remove the dirt which clings 

 to the roots, by washing. Make a study of plants one week 

 old, two weeks old, three weeks old, and four weeks old, 

 seeded one inch deep. Also make a study of plants two 

 weeks old and four weeks old, seeded three inches deep. (In 

 determining age of plant count time from date of seeding.) 



Make drawings of the plants at the different stages of 

 growth and at the different depths of seeding indicated. 

 Show in the drawings the four temporary roots which develop 

 first, and in other drawings show the permanent roots 

 which develop somewhat later and are sent out in whorls 

 from the nodes. Show how the distance between the tem- 

 porary roots and the whorl of permanent roots 'depends 

 upon the depth of planting. Show how the older plants 

 begin to tiller, by sending up new stems. The drawings 

 should include the root system, stems, and leaves and their 

 arrangement. 



