At one time this spring I thought I had found a new way of "bench-grafting" walnuts. Seven grafts, on black root, were made in December, and were planted directly in a frost-proof coldframe, as lilacs can be grafted. All seven grafts made good growth, that is, over three inches, by early May, but failed later. There is only one alive today, I do not think this an impossible method, but there must be a better way of handling to give success, such as attention to shading and careful watering. One may find more on this subject in "Propagation of Trees, Shrubs, and Conifers," by Wilfrid G. Sheat.
In our greenhouse work we have used several nutrient preparations, with poor to good results. There is one that has proved quite remarkable, and may be of use to the nut grower. Our concern has been to promote greener, healthier leaves, and the product "Ra-Pid-Gro" is most outstanding. Our tests in regards to nut growing are very limited. A pan of Chinese chestnut seed mixed in pure sand was set under the greenhouse bench last winter. The seed sprouted too early to be planted out, and trees have been left inside. Since the sand had no food value, Ra-Pid-Gro was applied to the leaves, allowing the drippings to go into the sand throughout the summer. Today, the little seedlings are indeed nice. Outside, a Persian walnut had yellow-toned leaves, and Ra-Pid-Gro was applied--now the leaves are green! It is amazing how quickly yellow leaves will become green. This appears to be a very useful product.
_I believe we can have scions too dormant to graft!_ Last winter I had to make a new scion-box for storage, so copied it after the Harrington method, sinking it in the ground north of some evergreens. Scions have kept perfectly--maybe too perfectly--because they were absolutely dormant at grafting time, and have given poor success. It was rather late to save scionwood when I received an order to cut some of Mr. Hostetter's "Special Thomas" wood, so I cut a little extra for myself, and some wood from a little seedling Persian walnut that I wished to hasten by topworking. The buds were very much swollen that day, and the terminal buds were partly expanded. At grafting time I was quite surprised to find the wood I had cut late to be in exactly the same condition as it was the day I cut it. When grafted, every scion grew--all nine grafts made of the little Persian walnut were smaller than a lead pencil--and were _pithy_ as well! This experience is so encouraging, I hope to have most of my wood in this advanced condition another year. Absolutely dormant wood might well be brought out of storage several days before grafting, in order to get it adjusted from winter to summer conditions.