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THE ESSENTIALS OF AGRICULTURE 



points to support this vegetative activity. When this growth 

 becomes less active, plant food begins to be stored. Some of 

 this food is stored in the buds, and fruit buds may be formed, 

 but fruit buds are not formed as long as all the food available 

 to the tree is required for vegetative growth. Therefore some 

 means must be used at times to hold the wood growth in check 

 and to allow a part of the food to go to the development of 

 the new fruit buds. 



Pruning may stimulate or check wood growth, and therefore 

 may hinder or help fruitfulness, according to the season of the 



year in which it is done. 

 Winter pruning, which 

 stimulates wood growth 

 and keeps up the vigor 

 of the trees, if carried 

 to extremes retards fruit- 

 fulness. Summer prun- 

 ing checks vegetative 

 growth, by removing 

 some of the leaves in 

 which plant food is 

 being elaborated, and 

 stimulates the forma- 

 tion of fruit buds for 

 the next year. By a proper practice of winter or summer 

 pruning, wood growth and fruitfulness may be kept in proper 

 balance; failure to prune results in a ruined tree (Fig. 132). 



356. Orchard cultivation general. Fruit trees, especially 

 when young, require good cultivation. The soil should be plowed 

 early in the spring and harrowed frequently during the season. 

 The exact time to stop cultivating varies according to different 

 conditions, such as climate, soil, and rainfall. Cultivation en- 

 courages rapid length-growth of the twigs and rapid thickening 

 of the whole growing layer of the tree. As length-growth ceases 

 this tender new tissue becomes stronger, harder, and more re- 

 sistant to cold and other injurious agencies. This hardening 



FIG. 132. Effects of failure to prune 

 apple trees 



