224 GROWTH OF TREES AND FORMING OF FRUIT BUDS 



2. Study a fruit spur. Determine: 



(a) Its age. 



(b) How many times it has borne. 



(c) The length of growth made each year. 



3. Examine an apple tree. Determine: 



(a) What percentage of the spurs have never borne any fruit. 

 (6) What percentage of the spurs are bearing fruit this year. 



4. Examine different varieties of apple trees. Determine: 



(a) Whether fruit is being borne, {h) terminally on shoots, (c) lat- 

 erally, or id) terminally on spurs. 



5. How old must a spur be before it will form fruit buds? 



6. Determine at what time of year terminal growth in length ceases. 

 Determine the same for fruit spurs. 



7. Ring some five-year-old apple trees, and see if they blossom any 

 sooner than trees which are not so treated. 



8. Put some nitrate of soda around an old, unproductive apple tree 

 and determine its effect on: 



(a) Color of foliage. 



(6) Length of terminal growth. 



(c) Length of fruit spur growth. 



(d) Amount of fruit buds formed. 



9. Explain the results secured in Studies 7 and 8 from a carbohydrate 

 and nitrogen relationship within the plant. 



