596 FUNDAMENTALS OF FRUIT PRODUCTION 



example, is more likely to get hardy plum roots from a nursery near home 

 than he is from a nursery whose chief clientage is in a section with milder 

 winters. 



For fall planting, northern growers will be more likely to get well 

 ripened trees from northern sources where the trees naturally mature 

 earlier. That this may assume importance is shown in the section on 

 Temperature Relations. 



Withal the mere mailing of an order to a local nursery is not always a 

 guarantee that the stock sent to fill the order is of local origin. Many 

 nurseries buy much of their stock from distant points. However, if the 

 stock is good and, in cases where a difference in roots is important, if the 

 roots are of the right kind, the grower need not concern himself greatly 

 about its origin. 



GRADES OF NURSERY STOCK 



Fruit trees are offered for sale by nurseries in several grades, which 

 are based on size as measured by either height or diameter or both. Since 

 the largest trees cost the most, the question whether there is any ultimate 

 advantage in them is of practical importance. 



The very fact of the grading shows the difference between individuals. 

 If this is a temporary matter, due to better immediate environment of 

 one tree in the nursery row there will be no final difference in the growth 

 and performance of these trees. If, however, the variation be an expres- 

 sion of inherent differences, the planting of lower grade stock may have 

 serious consequences. 



It is shown elsewhere in this section that bud mutations in the decidu- 

 ous fruits are uncommon; hence, uniformity in the tops may be presumed. 

 If there be a fundamental difference between the large tree and the small 

 tree in the nursery the cause must lie in the stock. Most of the stocks 

 used are seedlings and therefore more variable than the vegetatively 

 propagated stocks, some kinds more than others. Some of this variation 

 is undoubtedly temporary, but there are good reasons for thinking some 

 of it is more deeply seated. 



Webber^^i reports investigations with citrus fruits that bring out these 

 inherent differences in seedling stocks very strikingly. 



He summarizes his investigations in part as follows: 



"Nursery trees even when grown from selected buds taken from selected 

 trees differ greatly in size when they reach transplanting age. Commonly the 

 large trees are sold first and the small trees later when they reach the required 

 size. 



"Large, medium and small nursery trees of Washington navel and Valencia 

 oranges and Marsh grapefruit grown in comparative tests show that after 2H 

 years in the orchard the large trees remain large, the intermediate trees remain 



