n of such a high grade nut as
the Placentia with its susceptibility to blight. These things must be
considered and weighed carefully by the growers who are planting walnuts
in the blight sections. The various areas where walnut blight is not a
factor might profitably sacrifice heavy production to superior quality.

From our present knowledge it is very apparent that the disease
resistance of individual trees varies considerably from year to year and
under different soil and climatic conditions. The thorough testing of
resistant varieties will require considerable time.

_Nut Characteristics_

The character of the nuts is as variable as the trees themselves, not
only in the exterior appearance, but in the character of the meats as
well. The ideal commercial nut should be of medium size, about one and
one-eighth to one and one-half inches in diameter, of regular oval form
somewhat elongated, with smooth surface, and light brown color, and
uniform for these characters. The cracking quality of the nuts is quite
as important as their exterior appearance. The nuts should be well
sealed so they will not crack open in shipping. The shells should be
thin but strong, so the nut may be easily opened and the whole meat
taken out intact. The pellicle surrounding the kernel should be light
tan colored or silvery brown with a glossy waxed appearance attractive
to look upon. The meat should be smooth, and plump, averaging 50 per
cent or more of the total weight of the nut, and with a mild, pleasant
flavor, free from any astringency.

The shells vary all the way from extremely rough and unattractive
specimens to the smooth commercial type, as the Placentia, while the
color of the meats varies from dark brown to nearly white, and so on
through the other characteristics mentioned.

In the selection of varieties the walnut breeder is exceptionally
favored by the occurrence of large areas of seedling trees. According to
the 1910 census there were in the neighborhood of one and a quarter
million seedling trees growing in California. With this almost unlimited
material for selective use, it seems indeed reasonable that many
varieties will be selected in the future which are better adapted to the
demands of the industry than some of those now being propagated. By
means of hybridizing methods it is also hoped that some of the desirable
unit characters of the varieties now in cultivation may be recombined
into more nearly ideal varieties