CHAPTER XXX 

 FRUIT SETTING AS AN ORCHARD PROBLEM 



The preceding discussion has shown that certain fruit varieties are 

 completely self fruitful, others are partly self fruitful and still others are 

 self barren. With varieties definitely known to be self fruitful it is safe 

 to plant solid blocks to a single variety without making any provision 

 for cross pollination. The heavy production that characterizes large 

 plantations of the Concord grape, the Baldwin apple, the Montmorency 

 cherry, the Cuthbert raspberry and many other fruits is sufficient evi- 

 dence on this point. On the other hand many varieties that are often 

 considered self fruitful because in the average season they set a full crop 

 without the aid of any foreign pollen, are often greatly benefitted by 

 cross pollination. Thus though the French prune is generally considered 

 self fruitful and there are many large orchards consisting exclusively of 

 that variety, a higher percentage of its blossoms set when cross pollin- 

 ated with Imperial than when selfed.^^ In general it is good practice 

 always to make provision for cross pollination when planting the orchard, 

 unless there is definite knowledge that this is not needed for the variety 

 when grown under the conditions in question. Even though a variety 

 is entirely self fruitful under a given set of conditions the evidence shows 

 that in many cases the increase in the size of fruit resulting from the 

 stimulus of cross fertilization is sufficient to warrant planting together 

 two or more varieties which bloom at the same time. 



Fortunately the selection of varieties to secure effective cross pollina- 

 tion does not usually add many complications to the problem of variety 

 selection. In most fruits the grower prefers to raise two or more varieties 

 rather than a single sort. By choosing those that ripen at different 

 seasons the harvesting problem is usually greatly simplified and often 

 problems of tillage and spraying as well. When the orchard is to be 

 planted to two or more varieties for reasons other than cross pollination, 

 it is necessary only to make a selection such that their blossoming seasons 

 overlap to a considerable extent. When it seems best to have as large 

 a part of the orchard as possible consist of a single variety, the problem 

 of selecting one for cross pollination purposes is not materially different 

 than before. First and foremost, its blossoming season should overlap 

 that of the main sort. Then, questions of its maturing season, produc- 

 tiveness, market value and so on, should receive due consideration. 

 Another point that should receive attention in the selection of a pollenizer 



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