22 



UNIV. OF N. H. AGE. EXPERIMENT STATION 



[BuUetin 221 



best in the orchard. There is no evidence that all of the benefits thus far 

 observed are not due to the nitrogen and the nitrogen only. If we could 

 be certain that the increased growth and yield are due to the nitrogen only, 

 we could be certain that the applications of fertilizer have paid commer- 

 cially because the cost of the nitrogen on Plots 6, 7, 8 and 10 is only about 

 seven cents per tree per year, and on Plot 9 the cost is about twenty and 

 one-half cents per tree per year. 



The comparison of average yield per tree for the first ten years and 

 for the 11th to the 17th year inclusive, shown in Table X, indicates that 

 the trees in the sod plot have steadily lost vigor and declined, while those 

 in the plots which receive cultivation or cultivation and cover crop have 

 about maintained their vigor and jdeld of the first ten years. In those 

 plots receiving complete fertilizer with normal amount of nitrogen, the 

 trees have continued to increase in vigor and yield, while in the plots 

 receiving excessive nitrogen there is an increase in yield of over 50 per 

 cent over that obtained during the first ten years of the experiment. 



Table X — Woodman orchard — average yield in pounds -per tree 



1909-191S. 

 1919-1925. 



Plot 1— sod 



135 



84. 



Plot 5— 



cultivation 



and cover 



crop 



268.0 



Average Plots 6, 7, 

 8, 10-r-cultivation, 



cover crop and 

 complete fertilizer 



226.7 



278.8 



Plot 9 — cultivation, 



cover crop, complete 



fertilizer and extra 



nitrogen 



219 

 356.3 



Relation of Composition of Fruit Spurs to Fruit Bud Formation {Adams 

 Fund) 



Results of the work on relation of composition of fruit spurs to flower 

 production, which was begun in the season of 1921, have now been pub- 

 lished. 



The data on the second experiment in this series have now been com- 

 puted, tabulated and analyzed, and will be ready for publication at an 

 early date. Three types of spurs were sampled at frequent intervals 

 throughout the season as follows: 1. Spurs bearing fruit, from trees which 

 had blossomed fully and which bore a heavy crop of apples. 2. Spurs 

 not bearing fruit, from trees which blossomed heavily but from which 

 ever}^ blossom had been removed at blossom time. 3. Spurs not bearing 

 fruit, from trees which blossomed heavily but from which blossoms of 

 every second spin- were removed at blossom time. 



For the continuation of this work plans have been made to use only 

 non-fruiting spurs in order to eliminate the difficulties due to the influ- 

 ence of the apple on the fruit spur. It has also been decided that a smaller 

 portion of the fruit spur should be used than was formerly sampled. We 

 are interested principall}^ in knowing the chemical environment of the 

 primaiy meristem at the tip end of the spur, and it is possible or even 

 probable that the inclusion of older wood alters the results somewhat. 

 Samples taken during the summer of 1925 were, therefore, limited to the 

 new growth only, although by this method much greater labor is involved. 



