The Orchard Plant 61 



tissue that conveys the elaborated food is located. If the 

 ring of bark is taken from the trunk below all leaves or 

 leaf-bearing limbs, the tree usually will die. This must 

 be for the reason that no food can reach the roots from 

 the leaves, consequently starvation of those parts results. 

 On the other hand, if a ring of bark is removed from the 

 trunk above several limbs, the wound will usually heal, 

 provided, of course, that it is not so large that the sapwood 

 is seriously injured by drying out. A noticeable swelling 

 of the bark occurs on the upper side of the girdle, caused 

 by an excess of food, its movement downward having been 

 arrested at that point. Advantage is sometimes taken of 

 plants in horticultural practice in arresting the downward 

 movement of plant-food from the leaves by removing a 

 ring of bark. The upward flow of crude material from the 

 roots is not interfered with, but the food that has been 

 made over in the leaves cannot get past the girdle, con- 

 sequently those parts above this point receive an excess of 

 food. This practice is common in vineyards in some sec- 

 tions, and some varieties of grapes may be made to ripen 

 twenty days earlier than on unringed vines, and the ber- 

 ries grow from one-third to one-half larger. Earliness in 

 ripening and increased size is usually at the expense of 

 quality; consequently this practice cannot be recom- 

 mended as being worthy of general adoption. 



The Leaves 



The biblical saying that "all flesh is grass" is true to the 

 last degree, for there are no living organisms other than 

 green plants that do not, in the final analysis, owe their 

 existence to the leaves of plants or rather to the products 



