METHODS OF GRAFTING 235 



of, say, No. 18 or 20 size should be used just enough to 

 keep the parts in place until the grafts are planted. In 

 order that the thread may decay quickly, it should not be 

 waxed. Indeed, some propagators contend that binding 

 is a disadvantage because they claim that as the callus 

 forms and the stem expands the cord cuts the soft tissues 

 and thus favors the entrance of crown gall and hairy 

 root (Fig. 182). Therefore, they leave the grafts un- 

 wrapped, but use extra care in fitting the part's together. 

 306. Graft wrapping machines are coming into use in 

 some of the larger nurseries because they economize 

 time and cost and do work said to be superior to hand 

 wrapping. In a circular describing the "Reed-Bell" 

 machine the following passage (condensed) occurs : 



FIG. 191 WHIP GRAFTS WITH TOO MUCH CALLUS 



An account carefully kept during several weeks of a 

 grafting season shows the machine-wrapped grafts cost, 

 on an average, five cents a thousand for twine, 11 cents 

 for wrapping, a total of 16 cents a thousand ; a saving of 

 34 cents a thousand over calico wrapping. But what is 

 of more importance, the tension of the thread may be 

 adjusted to wrap the graft so tightly that it may be taken 

 by the root, thrown or shaken without risk of loosening. 



