I am going to ask Dr. Morris if he will present his paper and make his demonstration at this time.
DR. ROBERT T. MORRIS: I have had a good many experiences in grafting for a number of years. I have finally discarded most methods and have gotten down to rather simple principles. As a matter of fact this is the last word from my own point of view. During the past thirty or forty years I have changed my mind so many times on so many subjects that I have no confidence at all in anybody who puts any trust in me.
I am getting down to the splice graft. The reason why I didn't try it before was because it didn't seem reasonable to believe that the simple splice would hold. It was because I was so busy with many other responsibilities that on one occasion I neglected to brace some large splice grafts. Thus I learned that the splice graft would hold even through the very severe storms in our vicinity of Stamford, Connecticut. We have violent thunder storms and sometimes for a few minutes in advance of a storm we have a wind velocity of sixty or seventy miles an hour. If at the time the leaves happen to be wet the battering power of a seventy-mile wind is so tremendous that it will break out almost any form of graft. But my splice grafts during the past two years, simple splice grafts, subjected to this sort of storm, have not given way on a single occasion so far as I know, much to my surprise.
I will pass about some examples of the simple splice graft first and then show how we do it.
Here is a Stabler black walnut graft on common black walnut stock last year. For years I had been in the habit of cutting my scions and throwing the stubs away. I had a nice lot of hardy looking stubs in the grass and I said to myself "Why not try some of the stubs?" They made a very fine growth. I didn't lose one of them. Here is one of the big stub grafts and here is the growth it made last year. Here is another plain splice and the growth it made last year. This tree was killed by the ice in the river on my place last year. Sometimes in the spring we have great masses of ice come down that run through the orchard and kill some of my trees. That is the reason I cut off this one. I have only brought specimens that were injured but they show perfectly well. In this smaller splice you see I fitted the scion to the diameter of the stock. In the larger one I took no pains to do that. Furthermore the paraffin method was used. The scion is covered entirely with paraffin and I think you will notice, by rubbing your fingers over this stock, that the paraffin, although two years have elapsed, is all there. It is because I put it on in such a fine layer that it expanded with the growth of the scion.
Not always, but in order to make sure that my simple splice graft would hold, I have sometimes put in screws. I use flat-head, brass, wood screws, seven-eighths inch long.
I will put in some screws for you. So, if any of you fear that the simple splice grafts may not hold, put in screws and study Basil King's book on the "Conquest of Fear." This is a black walnut graft that I put in late this year with screws. You can see the screws projecting from the paraffin cover. I do not care if the screw sticks out quite a little distance. It is covered with a thin layer of paraffin. This graft caught and started to grow but was killed off by sprouts springing from the butternut in great masses before it had a chance to assert its own individuality. The graft, however, is all complete. Here is another one, where the screws are projecting, which was killed off by the stock sprouts below, with the repair all complete. In fact it would have gone on well enough to a successful growth if I hadn't been away and allowed the stock sprouts to grow. This shows, incidentally, the thin layer of paraffin. If we use a thick layer of paraffin it will crack and not be successful.
The simple splice graft is a very simple affair. In the first place it is well to have a knife with which you can shave. I think, Mr. Chairman, you could shave with that (handing knife to the President). That is the sort of edge to use in all our grafting work, the sort of edge that will bring terror to the heart of the mother of boys. I find very few people who really can sharpen a knife. I have been surprised at the small proportion of people who are really able to do it. They put on a feather edge, or they leave a round edge, or at any rate they are unable apparently to use the little finesse required to put the finishing touch on a really good knife. Above all other essentials is this little piece of carborundum made at Niagara Falls, F F Fine. Moisten it, hold it in the fingers this way, and then by simply rubbing it back and forth in this way you can put on the very finest edge. Do not use a knife unless you can shave with it because it is quite essential to have the cambium layer very nicely kept.
A couple of years ago hearing of Mr. Biederman's work in the use of the plane for grafting with his Persian walnuts, it occurred to me to try it with shagbark hickories. I went out in the barn to look for a block plane and I found three or four rusty ones. I wondered where they came from and then it occurred to me that about eight years ago I had thought to try the plane, and did try the plane, but it was not a success. That was before we had any success in grafting hickories. Now we may use the plane almost to the exclusion of the knife in cutting our scions of hard wood trees. Perhaps the majority of scions are shaped with the plane rather than with the knife because it gives a much truer surface. The block plane, then, I believe, is to be used more and more instead of the knife because of the very true surface that we make on the scion and on the stock and very quickly.
Of course with a small scion of this sort that would be about the slope that I would use for my ordinary splice. Fasten the splice together and simply wrap it with raffia. There is an ordinary splice graft fastened with raffia. That is the simple form that has given me the best results and I have tried out all the fantastic forms of grafting.