1916.] PUBLIC DOCUMENT — No. 31. 47 a 



co-operation and advice of other members of the department of 

 pomology. 



4. Some experiments in the formation of heads on young 

 apple trees, using different methods of pruning, are now under 

 way by Mr. Armstrong under direction of Dr. Shaw. 



5. Perhaps the most important experiment under way in this 

 division is the one conducted by Dr. Shaw in the correlation 

 existing between stock and scion in grafted fruit trees. This 

 project is an extensive one and is undertaken to cover a con- 

 siderable term of years. It is now getting under way. 



8. Dr. Shaw has also been making extended studies of tree 

 and leaf characters in different varieties of apples. Much inter- 

 esting material' has been collected. 



7. Extended practical experiments in orcharding management 

 are being conducted by Professor Sears. The principal prob- 

 lems in hand are as follows : — 



(a) Experiments in spraying, with special reference to use of 

 oil on apple trees. 



(b) Comparative test of cover crops. 



(c) Top grafting experiments, designed to test the influence 

 of stock upon scion in top-worked apple trees. This experiment 

 is naturally closely correlated with the stock and scion experi- 

 ments planned on a larger scale by Dr. Shaw. 



(d) Extended observations of varieties of fruits. 



(e) A comparison of southern-grown nursery stock with 

 northern-grown. 



(/) A comparison of one-year trees against two-year nursery 

 trees in orchard planting. 



(g) Experiments in the pruning of nursery trees at planting 

 time. 



(h) Summer pruning experiments, which thus far have given 

 chieflv negative results. 



