Northern Nut Growers Association Report of the Proceedings at the Twenty-Fourth Annual Meeting | Page 6

Experimental Work in Hybridizing Filberts and Hazels
By MILDRED JONES
Lancaster, Pennsylvania
The first crosses of the hybrid filberts were made in the year 1919. The small plants when taken from the nursery row were set 5 x 8 feet with the thought in mind of taking out every other bush in the rows when they began to crowd, and in case they were of value they could be transplanted to a permanent place. It was not thought that many of the plants would bear superior nuts promising enough to keep longer than to observe the type of nuts the bushes bore. The first lot of plants, which were mostly of the Barcelona cross, bore in the fall of 1924.
The object in view mainly was to produce, if possible, a variety or varieties that could be made a commercial proposition here or elsewhere in the eastern U. S. Not very much was thought at the time about the flavor or the quality of the kernel. The main thought was to get away from the corky substance adhering to the kernel of the most of the filberts. Barcelona, the main commercial nut in the West, has a lot of this, which makes the kernel unattractive and is probably more or less injurious to the digestive system because of the tannin content. After this fault was eliminated it was going to be necessary to work for size and quality of the nut.
The filbert blight has not been found on our place, so not much stress was put on the point of producing a blight-resistant or blight-free filbert. Probably if we had the filbert blight we would consider it more seriously.
The method used in crossing these hybrids was to remove the catkins on the pistillate plant at any time before they developed and scattered their pollen. The wood containing the catkins to be used for pollinating was observed closely in order to bring it in at the same time with the Rush pistillates by cutting and holding back in a cold cellar after the catkins were swelling well. This was the Barcelona which blooms very early.
The Italian Red, Cosford and Giant De Halles bloom later than the Rush so this was another problem. These were forced by cutting and putting in a sunny window. In cutting wood for pollinating, the cuttings should be large. The stored up starch in the wood then gives the catkins more to draw on. Apparently the filbert catkins and pistillates develop entirely from the stored up starch in the wood and do not draw on the roots at all. This being so it was figured they would develop just as well off the bush.
The last pollinating on the Rush was done in the spring of 1921. The catkins appeared to be all right and the limbs were cut and stored in the cellar. These were taken from the DuChilly. Finding they did not respond promptly to warmth it was seen that the catkins were drying up and getting stiff. As Father was very anxious to use this variety he tried soaking the limbs in water and then exposed them to the sun. Some of the catkins only swelled and then appeared to stop. The soaking was then repeated making it several hours and again they were exposed to the sun and warmth. Most of them developed nicely after this treatment. As those on the bush dried up and turned black it was thought probably the pollen used after treated as just mentioned was not good, but the pistillates developed promptly after being pollinated and the bush produced a large crop of nuts. I suppose these had been injured in the winter, but it would seem surprising that they could be made to develop artificially and the pollen be good.
It was found that Rush crossed Cosford made the largest nuts but the kernels of these nuts were not of the best quality.
On our eastern market I think it will be found that the longer type nuts will bring the premium in price. I find in selling the nuts that people mostly desire the longer nuts, but will take the other nuts if they cannot get the longer ones.
This past spring we tried to graft several of the most promising hybrids in the older block of trees. We used the modified cleft graft method and we set the grafts on layered plants of the Barcelona filbert which were lined out in April. We grafted them in May after the layers had started to grow. Out of 200 plants grafted we have growing 16 nice plants from 18 to 24 inches tall, an 8% stand. The roots of the Barcelona layers died also on the grafts that failed to live. I believe the main trouble in this experiment was that there was not enough