228 CALIFORNIA FRUITS: HOW TO GROW THEM 



cherries has vastly increased their proportionate production as com- 

 pared with the choice black and red varieties, which are still popular 

 as a table fruit. 



It is the experience of growers that the cherry is grafted over as 

 easily as the pear or apple, if the tree is healthy. In large trees as 

 many as fifty or one hundred grafts may be set, choosing the smaller 

 limbs, even if you have to go pretty high in the tree. J. W. Cassidy, 

 of Petaluma, used to advise grafting before the sap begins to flow 

 in the winter, or if not done then, wait until the buds are well 

 advanced or the tree in bloom. He has trees which were over thirty 

 years old before they were re-headed, and they made fine tops of new 

 and healthy wood, and produced abundantly. The cherry is in fact 

 a very easy tree to graft by the usual top-grafting methods. 



PESTS AND DISEASES OF THE CHERRY 



The disease of the cherry which is most heard of is the "gum," 

 or overflow and condensation of sap, which, if left to itself, often 

 induces decay of adjacent bark and wood. Without attempting to 

 explain the cause or causes of the unhealthy exudation, it may be 

 said that prompt treatment of certain manifestations is desirable, and 

 in others the tree should be cleansed from the flow. Where the 

 gum exudes on the side of trunk or limb, the thin outer bark should 

 be pared away with a sharp knife, the accumulation of gum and sap 

 removed, and the wound painted with lead and oil paint, or covered 

 with grafting wax. 



Gum in the crotch should be cleanly brushed out when softened 

 by the winter rains. If allowed to remain, it becomes sour and 

 offensive and may injure the tree. In places where two or three 

 limbs come out close together a kind of cup is formed, which will 

 hold the gum from one year's end to another, and in its soft state, 

 leaves, sticks, cherry pits, dust; and dirt will stick and hang and 

 sometimes the mass becomes very foul. By this collection also, a 

 nest is made for all manner of insects, bugs and worms. Another 

 evil in letting the gum stay on is, if the rain does not wash it off clean, 

 it runs down the trunk of the tree and makes the bark look bad, 

 and if it is very thick on the 'bark when it dries, it will contract and 

 crack the bark crosswise, and is very injurious to the tree. 



Gumming in the crotch can be largely avoided by starting the 

 young cherry as advocated in the chapter on pruning. Branches 

 which emerge from the trunk at separate points and at wide angles 

 seldom gum ; those which are crowded together or emerge at acute 

 angles gum badly. In shaping young trees a gumming joint sometimes 

 may be clearly cut out and those branches selected to remain which 

 start out at a wider angle; in older trees there is nothing to do but 

 keep the fork clean, as already described. 



There are cases reported in which gumming of old trees has been 

 stopped by allowing the ground to lie uncultivated, weeds being cut 



