ROOT AND LEAF CUTTINGS 



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may be produced from a single tuber. Sweet potatoes are 

 propagated in this manner. Irish potatoes are propagated 

 usually by using the whole tuber or a portion of it contain- 

 ing one or more eyes. Many experiments have been per- 

 formed to ascertain the ideal size to plant for seed to obtain 

 the maximum yield. In most cases, the larger pieces have 

 given the greater yields, and good-sized potatoes cut in 

 halves have yielded more than small potatoes similarly 

 cut, and more than larger ones cut into many pieces. 



Root Cuttings. Of the plants commercially propagated 

 by root cuttings, the horse-radish and blackberry are 

 familiar examples. The smaller roots 

 are cut into pieces one to four inches 

 long as soon as the growth ceases in 

 the fall, and are packed in boxes with 

 moist sand or moss. They are then 

 placed in a cool cellar for the winter 

 and planted out of doors in the spring. 

 It is difficult to tell the base from the 

 top of horse-radish cuttings, and as 

 it is necessary to plant them in an 

 upright position in the soil to obtain 

 good straight roots, the cuttings 

 are made with a diagonal cut at 

 the bottom and a horizontal cut 

 across the top. Blackberry cuttings 

 may be planted horizontally in the 

 soil. 



Leaf Cuttings. Plants, like the 

 begonias, having thick fleshy leaves, 

 store large quantities of plant food either in the body 

 of the leaf or in its larger ribs. When these ribs are 



Fig. 12 x. A rooted leaf 

 cutting of Rex Begonia, 

 showing formation of new 

 plant. 



