BENCH-GRAFTING RESISTANT VINES. 225 



Another method, new and not thoroughly tested as yet, 

 was tried with a few Rupestris St. George cuttings, Mon- 

 deuse being used for scions. This method originated in 

 France, and is called " End to end " grafting. Its nature is 

 shown in Fig. 176. The ends of stock are cut at an angle of 

 about 70, and are held together by a piece of galvanized- 

 iron wire which is pushed into the pith of each piece. The 

 number of successful grafts was low, but those which did 

 unite made such excellent unions that the method seems 

 worthy of further trial. It is especially promising for 

 machine grafting. 



Binding Grafts. Raffia, treated as explained on page 222, 

 was used for binding the grafts. The raffia seemed to have 

 deteriorated somewhat during the twelve months it had been 

 allowed to hang in an open shed. It was weaker than 

 usual, and some of it rather brittle. It was cut into lengths 

 of about 12 inches. 



It has been shown that the grafts would do better without 

 any binding, but for two reasons, first, because it is difficult 

 to handle unbound grafts without disturbing the union ; and 

 second, because the callus does not form simultaneously on 

 all parts of the Union, and the first formed tends to push 

 apart the stock and scion, thus making it difficult or 

 impossible for all parts to unite. The object then in binding 

 is to use as little raffia as is compatible with the thorough 

 firmness of the union. The free ends of both scion and stock 

 should be made firm with about two turns of the raffia, and 

 the rest with wide spiral turns, which leaves as much of the 

 union in direct contact with the sand as possible. The sand, 

 while keeping the union sufficiently moist, does not com- 

 pletely exclude the air, which is necessary to the formation 

 of healing tissue. A somewhat closer tying than this was' 

 adopted in these experiments, on account of the weakness of 

 the raffia used. 



The grafts were tied in bundles often, and then treated in 

 various ways to aid their uniting. 



METHODS OF AIDING CALLUSING. The main reason for 

 callusing the grafts before they are put in the nursery is 

 that we can have more perfect control of the conditions 

 which favour the formation of callus. Those conditions are 

 an even and not too low temperature, and a moisture content 

 of the soil in which the grafts are callused, not exceeding 10 

 per cent., and not falling below 5 per cent. 

 10890 P 



