A UNIT IN AGRICULTURE 43 



PLANT PROPAGATION. 

 Ex. 28. Absorption of Water by Seeds. 



Soak a few beans in hike warm water. Notice closely the appear- 

 ance of the bean at the end of ten minutes and at the end of forty 

 minutes. What changes in form of surface and size of bean? With 

 a hand lens, examine the bean closely to find the place where the water 

 gets in. Try the same experiment, using three or more of the fol- 

 lowing seeds : squash, apple, gourd, pea, corn, pumpkin. 



Ex. 29. Effects of Temperature Upon Seed Germination. 



Prepare two pieces of canton flannel a little larger than a dinner 

 plate. Wet one piece and place it on the bottom of the plate. On this 

 place a few seeds squash, corn, or butter beans. Moisten the second 

 piece of cloth, lay it over the seeds and cover with a pane of window 

 glass. Prepare a second germinating apparatus in precisely the same 

 way. Place one of the plates in a warm place, 80 to 120 degrees if 

 possible ; place the other in a cold place at or near the freezing poini 

 if possible. (The refrigerator may be used in summer.) At inter- 

 vals of two days examine each and note results. 



Ex. 30. Effects of Air Upon Seed Germination in Water. 



Fill two small wide mouthed bottles with water. Shake one thor- 

 oughly and put a few seeds of different kinds in it. Remove the water 

 from the other bottle and boil it. Pour it back into the bottle and 

 put in it the same number and kind of seeds. Cover the surface of 

 the water in the last bottle with oil, set both in the window and note 

 results. In which bottle do the seeds germinate best? Why? Exer- 

 cises 6, 28, 29 and 30 indicate quite clearly the conditions of seed 

 germinatidn. What are these conditions ? Give an illustration from 

 your own experience on the home farm or garden to show that all 

 these conditions must always be present when seeds germinate well. 



Ex. 31. Purity of Seeds. 



Material : clover seed from several sources, alfalfa, timothy, wheat 

 and millet. The price of each sample should be ascertained. Weigh 

 out three grams of seed and spread on a sheet of paper. Using a 



