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 root system to carry the graft rather than the fault of the grafting, as most of the grafts started to grow. We should have tried grafting on layers established one year and we will try this next spring.
We have several very promising filberts in the older block of bearing plants. The Buchanan, No. 92, was named for President Buchanan, the only President of the U. S. from Pennsylvania, whose home is in Lancaster. No. 200 is also an excellent plant and was classed by my Father as one of the best in the collection. This plant has not been given a name as yet. I would like to have a name suggested that would be suitable. These two plants just mentioned bear nuts very much the shape of Italian Red. The kernels come out with little or no corky substance on the kernel. The flavor is very good and the plants have borne very well. We have a plant called "B." Letters were given to the plants where mice got in the seed beds and mixed the nuts. The nut of this plant is more the shape of Barcelona and is very good. It also bears well.
In the younger block of plants we have quite a few promising plants but these must be tested further before we can say anything definite for or against them.
I notice considerable leaf burn in the block of hybrids since the severe storm we had two weeks ago. Quite a few of the nuts were knocked off too but there is still a good crop which you will see tomorrow.
Since my Father died we have not done any hybridizing. We hope to do so in the future as the work is very interesting.