Soil Requirements
The Japanese walnut seems to thrive on many soil types ranging from a heavy clay to a light sand, but does best on what is popularly known as a well drained fertile sandy loam with a friable clay subsoil. It will not do well on strongly acid soils and those who have planted trees on such soils should apply lime in liberal quantities. Poorly drained soils or very light soils deficient in humus are also not suitable.
Tree and Nut Characteristics
The Japanese walnut has several characteristics which make it desirable as an ornamental and as a nut-bearing tree. It grows rapidly, has large numerous luxuriant leaves which give it a tropical effect, and usually has a symmetrical outline. It bears early, sometimes in the second year from the graft, yields heavily and is often reported to yield regularly.
A heartnut tree owned by Mr. Sylvestor Kratz of Jordan Station, Ontario, produced nearly seven bushels of husked nuts one season and Mr. J. W. Hershey reports a yield of ten bushels of heartnuts from a tree near Olney, Pennsylvania. He also reports a cash return of $50.00 from one tree grown by Mr. Killen of Felton, Delaware. These were heartnuts and sold for 50 to 75 cents a pound. Mr. J. V. Gellatly, Westbank, B. C., obtained a yield of ten bushels of unhusked nuts from a heartnut tree of medium size. The yields from the common type, J. sieboldiana, have also been heavy, but since no figures are available no definite statements can be made.
In the Japanese walnut as in other species of nuts there is marked variation in nut characteristics, such as size, thickness of shell, cracking quality, extraction quality and flavor of kernel. Heartnuts have been found ranging from 1/2 in. to 1-3/4 in. in length. The largest heartnut I have ever seen came from Gellatly Brothers of Westbank, B. C. This nut was 1-3/4 in. long by 1-1/4 in. wide and was fully 1 in. thick. I also located a fine Sieboldiana type which is said to be the largest found up to date. (See specimens in jars).
Some of these good kinds possess excellent cracking and extraction quality. Mr. John Hershey of Downingtown, Pa., reports several good easy-cracking strains not yet introduced and Mr. Gellatly has one called O. K. that can easily be cracked with a hand nut cracker. I have also found one that I believe is a hybrid and which has excellent cracking and extraction quality. These specimens came from a seedling heartnut grown by Mr. Claude Mitchell, Scotland, Ontario. The nuts are longer than any heartnut found so far. The kernels in many cases fall out whole or in halves. This strain received the O. K. of Prof. Reed and Dr. Deming and as you know when a nut gets by either of those gentlemen it has to possess some merit. The good result produced by nature without any assistance from man suggests the possibility of getting even better results from parents of superior characters. I believe the Japanese walnut offers interesting possibilities in breeding with the butternut and possibly the black and English walnut. Definite plant breeding work should be done with these species as well as with all other species of nuts.
The Japanese walnuts generally grow fast but usually do not attain a large size. In most cases the trees rarely grow more than 35 feet tall with a spread of 30 to 50 feet, but occasionally specimens attain much larger size. The writer saw a heartnut tree on Mr. Kratz's farm near Jordan Station, Ontario, which had a trunk diameter of 2 ft., a height of 35 ft., and a spread of 64 ft. Near St. Thomas, Ontario, there is a large sieboldiana tree which is 75 ft. across the top and is about 45 ft. tall. Mr. Ricks reports a huge tree near Olney, Pennsylvania, that is 80 ft. across the top and 60 ft. tall and Dr. Deming reports a tree with a spread of 100 ft.
Varieties
Through the efforts of the Northern Nut Growers Association members several good varieties have been found and propagated. These varieties have been widely distributed but have not been extensively planted. The results are variable as might be expected, but generally the reports are satisfactory. In the eastern states the following varieties seem to do reasonably well: Faust, Bates, Ritchie and Stranger. In British Columbia, Messrs. J. U. and David Gellatly have located several very good strains such as Gellatly, O. K., Calendar, Walters and Rosefield. These newer varieties from the West have several good characters and are worthy of a wider trial in the East.