BULLETIN 231] WALNUT CULTURE IN CALIFORNIA. 233 



off trees a foot or more in diameter directly through the main trunk 

 and then worked the following year on the sprouts coming from this. 

 Such a method is of doubtful expediency on account of the great 

 liability to decay of so large a cut surface. 



The time chosen for cutting off the top or limbs for top-grafting is 

 usually that when the grafting is done, namely, just before the trees 

 commence to send out new growth in the spring. One of the most im- 

 portant considerations in this respect is that of the bleeding of the 

 trees when cut off, which sometimes takes place quite profusely. No 

 general statement can be made as to the time or conditions under which 

 such bleeding takes place, or does not take place, since its occurrence 

 is quite irregular. In some soils, especially light sandy ones, and in 

 some seasons it seems almost impossible to find a time when the trees 

 can be cut off without bleeding. We have seen practiced a method of 

 cutting off the tops and branches early in the winter, in December for 

 instance, when there is practically no danger of bleeding, and then at 

 the time of grafting making a fresh cut just back into normally green 

 tissue. In this way some who have had trouble with bleeding have 

 thought that much benefit was obtained. Another method consists in 

 cutting off the tops just before grafting and then, if bleeding takes 

 place, boring several half-inch holes in the butt of the tree near the 

 ground in order to allow the surplus sap to escape at that point. Usually 

 the tops may be cut off at the proper time for grafting without any 

 serious trouble from bleeding except now and then in certain individual 

 trees, or sometimes in certain individual orchards on an especially warm 

 soil. The cuts should be made carefully in order not to split and tear 

 down the stubs. The best method consists in first making a cut on the 

 under side in the case of a horizontal limb, or cutting partially through 

 on one side in the case of a tree cut off in the trunk, then cutting com- 

 pletely through on the other side an inch or two above the first cut. 

 After taking off the limb or top a fresh cut is made clear across, just 

 below the first cuts, in sound wood. 



The question sometimes arises, especially in working over good-sized 

 or large trees, whether to cut off all the limbs at one time or to work 

 over only part of the top the first year, leaving part of the original 

 branches over until the second or even later years, thus extending the 

 grafting over two^ or more years. Most experience has been against 

 the latter method and in favor of cutting off and grafting the whole 

 top at one time, even with the largest trees. Ordinarily, if part of the 

 original top is left, very little growth results from the scions, the whole 

 vigor of the tree seeming to go into the remaining portion of the original 

 top. We have heard the plan proposed of grafting the north side of 

 the tree fiist, then the east, south and west in successive years, this 

 idea being based on the well-established observation that grafting is 



