A proper and careful cutting of the tree beforehand is important. It appears that to cut the top completely out while the tree is dormant, so disrupts the routine circulation that the few lower branches which are left intact, are well taken care of and, it seems to me, that this, together with the stimulation of WOUND REPAIR by cutting and allowing time enough for the cells to get into action, was the prime reason for the 100% success in the three Hales and the cause of the 100% failure in the other Hales tree. Other methods of controlling the circulation are of course drainage, irrigation, mulching, location of the orchard, placing of condensers of moisture, such as stones and other hard substances beneath the trees, and many other contrivances which are in use, and which I shall not discuss. With reference to stimulation of cellular activity we are considerably concerned. In medicine I have found the subject of wound repair and immunity most interesting, the two subjects seeming to be more or less related. Some animals will repair wounds and immunize readily, while others will not. In a general way young healthy animals and human beings immunize most readily, while older ones frequently fail almost entirely. Interestingly enough plants seem to be strangely similar in this respect, and the thing that stimulates cellular activity for defensive purposes (immunity) apparently stimulates growth and wound repair. The thing that stimulates most actively for a special purpose is the thing itself, the best stimulant for wound repair being the simple injury. To illustrate briefly: In my work last summer I came in contact with two enemies, yellow jackets and copperheads. The copperhead stimulated me to carry a club in defense, while for the yellow jacket the club was of little value and I rather preferred carbon bisulphide. Had I ignored my senses and allowed nature full sway, as a tree does, the snake would have injected his venom and the yellow jacket his toxin, and my cells would have accepted their only alternative and proceeded at once to build up a specific defense, after which they would have been in better shape for development, providing the poison would not have been so great as to prove fatal. Injury to a tree certainly does stimulate wound repair, defense and growth. It is well known that trees with many transplantings, root injuries, transplant much more readily, and the nurserymen use this method of stimulation as a routine procedure. I learn in Florida that in order to transplant a good size palmetto, they are in the habit of digging down on one side and cutting the roots the year before removal. It will then transplant more readily. Pruning has the same cell stimulating effect if done at a time that will retain the stored nutrition. An attack of disease just as surely stimulates cellular activity and growth but it is too frequently followed by disaster.