The defects of the Japanese walnut most frequently mentioned are lack of flavor and pollination deficiencies. Some trees produce staminate flowers too early for proper pollination and thus do not yield a crop unless another good pollinator grows nearby.
Susceptibility to sun-scald and to San Jose scale are some other weaknesses. Many of the trees commonly grown are undesirable because of small size of nuts, poor cracking quality and too mild a flavor.
A careful consideration of the good and bad characters of Japanese walnuts suggests the following program before the culture of this species can be placed on a sound basis.
1. A systematic and thorough search of the United States and Canada for productive trees yielding nuts of large size, of good cracking and extraction quality and pleasing flavor.
2. The propagation and wide dissemination of these superior strains to members of the Northern Nut Growers Association and particularly to experiment stations where there seems to be a striking lack of information on this and other species of nuts.
3. Systematic improvement by means of hybridization with the butternut and other suitable species.
A program such as this would yield information of great value and would probably establish the culture of this species on a sounder basis than it now is. Until this has been done the logical course to follow is to plant the best varieties in limited numbers in areas where the black walnut thrives and even in areas too cold for the black walnut.
The President: I have been connected with experiment stations and colleges for the past number of years but I was quite surprised to find such a general lack of knowledge of nut trees, and especially of this species. The members of the experiment stations who are here do not need to feel badly. My remarks wouldn't apply to them.
Member: Any varieties of this that bloom late?