1919] HORTICULTURE. 649 



elusive that, in all our leading commex-cial varieties of apples observed, a given 

 fruit spur is not usually able to mature fruit and at the same time develop a 

 fruiting bud for the following year. On Gano, Rome, and York only an occa- 

 sional fruit spur produces blossoms two years in succession. Jonathan, Grimes, 

 and Winesap produce blossoms two years in succession on the same spur some- 

 what more frequently. It is concluded that Gano, Rome, and York tend to pro- 

 duce only alternate year crops because in the fruiting year practically all their 

 individual fruit spurs produce fruit, leaving very few nonfruiting spurs to 

 blossom the following year. On the other hand, Jonathan and Winesap give 

 more regular aimual crops because only a portion of the fruit spurs set fruit 

 in a given year. 



Observations since the experiment began show that an individual fruit spur 

 has a fruiting life history ranging from two to eight years. Few spurs, however, 

 begin to bear before they are three years old and but few retain their bearing 

 form beyond six years of age. Under favorable conditions spurs older than 

 this develop into longer branches, upon which a new crop of fruit spurs develop. 

 A study of the above-named varieties on different types of soil has shown that 

 there is apparently no relation between the character of the soil In which the 

 tree grows and the alternation of the individual spurs. Removing the blossoms 

 from a tree by accident or design may result in a change in the fruitful year. 

 Removing the blosi^oms or fruit (thinning) of an individual fruit spur or branch 

 may to some extent bring about this change. 



Sap from bearing spurs has slightly higher concentration (lower freezing 

 point) during a considerable portion of the year than sap from nonbearing 

 spurs. Sugar and starch are present in slightly greater amounts in the bearing 

 spur than in the nonbearing spur. If the blossoms or fruit are removed from 

 a bearing spur this available sugar is apparently directed toward the develop- 

 ment of a fruit bud for the following year. Trees pruned to a low head and 

 just now reaching fruiting age are developing fruit spurs in far larger num- 

 bers than are high-headed trees of the same age. Apparently long stems and 

 branches not only dry out in the sun in late winter, but they bend and twist and 

 restrict proper flow of sap. In short-stemmed trees there is no such restriction 

 to the ready passage of sap, fruit spur development is better, and a succes- 

 sion of fruit spurs can be more easily renewed than by pruning. 



In the orchard management investigations being conducted by J. C. Whitten 

 and C. C. Wiggans, the number of blossoms in the spring of 1918 was much 

 larger on the sod plats containing alfalfa, clover, or timothy than on the 

 plats given clean tillage or tillage followed by late summer and autumn cover 

 crops. Fruit spur development is much more marked on the sod plats, al- 

 though potential fruit spurs are forming on the tillage plats. The vigor of 

 wood growth is most marked on the tillage with cover crop plats. Thus far 

 no linal conclusions are drawn as to the best system of orchard management. 



Fruit nutrition studies were continued during the year by J. C. Whitten and 

 C. C. Wiggans. No data were available upon the effects of the various fertil- 

 izers upon the peach crop, since the fruit buds of the peach were killed 

 throughout the State as in the preceding winter. It was again noted that the 

 nitrogen-fed trees were in much more vigorous condition than were the trees 

 which received no nitrogen. No visible effects were observable where potash 

 or phosphorus, either singly or in combination, were applied to peaches in past 

 years. Summing up the results thus far secured with both peaches and 

 apples, it is concluded that on the various Missouri soils under test there is 

 no apparent advantage in adding mineral fertilizers even up to the time that 

 the orchard reaches mature bearing age. The experiments have not been con- 



