106 LABORATORY LESSONS IN GENERAL SCIENCE 



growth of plants can be taken in through the roots, in what 

 condition must this material be ? 



4. That the young tree be well nourished from the first 

 after transplanting, (a) what form of root is desirable ; (b) 

 what should be the condition of the soil filled in around the 

 roots ; (c) why pour water about the roots, and what amount 

 should be used; (d) why press the earth firmly about the 

 roots ? 



5. Why is such great harm done in an exposure of the 

 rootlets to air and sun even for a very short time? While 

 the planting of trees is going on, how may the roots of those 

 awaiting planting be kept from injury? What purpose is 

 served by leaving two or three inches of top soil loose and o'ry 

 around each tree planted? W T hat is meant by "heeling in" 

 trees for later planting ? 



6. In what manner may young trees newly set be pro- 

 tected (a) from ill effects of heavy winds ; (6) from animals ? 

 Why is it harmful to the young tree (a) to break off its 

 branches; (6) to pull it about, loosening it in the ground? 

 Why is it harmful to tramp the soil about the tree by run- 

 ning over it? 



7. What is the chief use of leaves to plants? In trans- 

 planting trees why is it generally best to trim off almost all 

 side branches, and to cut back the top ? When does a young 

 tree become able to provide for much leaf surface? What 

 is transpiration in plants? 



8. Where a young tree is to be grown for fruit-raising, 

 what shape of top is desirable ? Why so ? Why is it better 

 to prune a little every year and not at long intervals ? Why 



