ON PAPER-SHELL WALNUTS 
white and most delicious of flavor. The thin shell 
is also white. The tree bears enormous crops, and 
about its only defect is that it may, on occasion, be 
caught by the late spring frosts. But even with 
this defect, it produces a larger crop of nuts than 
any other tree that I have seen. 
HYBRIDIZING WITH THE JAPANESE WALNUT 
The experiments in which I hybridized the Per- 
sian Walnut with the California Black Walnut, 
producing the tree named the Paradox, have been 
outlined in an earlier chapter, and will be referred 
to again in a later one. 
It will be recalled that this tree has extraordi- 
nary qualities of growth, but that it is almost ster- 
ile, producing only a few nuts on an entire tree, 
and these nuts of the poorest quality. 
Another hybridizing experiment that had great 
interest was that in which the Persian Walnut was 
crossed with the Japanese walnut, known as Jug- 
lans Sieboldii. The Persian walnut in these crosses 
was used as the pistillate parent. 
The first generation hybrids of this cross show 
a combination of qualities of the two parent spe- 
cies as regards the nuts, which are not borne abun- 
dantly. The foliage is much larger, however, than 
that of either species, the bark is white, and the 
tree itself is of enormously enhanced growth. It 
probably makes about twice as much wood in a 
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