The failure to fruit is due to many different factors. Some of these are external such as frost and rain at pollen shedding. There is nothing you can do about these. Other factors are internal and determine the formation of fruit buds. If the tree is carrying an exceptionally heavy crop, the chances are it will not have enough of the material which determines the setting of buds to form buds for the following year. With the apples we can do something about this by thinning the crop at the time it blooms. With walnuts, I don't see how we are going to do it. Fertilization is another approach. Certainly we should make conditions just as favorable as possible for growth and for the development of the buds and by all means control insects and diseases. If you do not have a good leaf surface good crops will not be set the next year. It's a complex problem, but I don't think it is insoluble. DR. MCKAY: Mr. Chairman, in connection with this matter of annual bearing of black walnut trees we believe that in doing all sorts of things you will not influence the yielding of most of our black walnut varieties. The black walnut, _Juglans nigra_ is probably--some of us think, at least--constituted genetically in such a way that the varieties we have do not yield annual crops simply because they are not constituted that way. I know some of you may disagree with me, but one of the greatest arguments for this idea is the fact that in some of our other nut species we do have varieties that are genetically heavy producers. For instance, we have a selection of Chinese chestnuts right now that will bear annual crops on the poorest soil under any conditions imaginable. You can graft scions of that tree on other stocks and plant them anywhere you choose under differing conditions and it will have a heavy set of burs. It may not fill the nuts, it may not attain the size, but genetically speaking, inherently it is a heavy bearer. Perhaps our black walnut species are inherently not annual producers. This is hard to prove, I admit, because the breeding of the species takes so long that we cannot actually demonstrate it. We have felt also that the black walnut species as a whole does not have the characteristics of thin shells and good cracking qualities that we want. For this reason we have begun a program of crossing the black walnut with the English or Persian walnut, in order to get the thin shell that we want from the other species. Perhaps the same thing is true in the question of yield and the species as a whole does not have the characteristic of yielding heavy annual crops. MR. MAGILL: I think we can readily see that we haven't settled this problem but it is time to close the discussion.