Botanic Garden
Record 24:62_) it was stated: "In our form of the Chinese chestnut only
one, if any, bur appears at the base of the flowering branch. The dwarf
species, _C. seguini_, from eastern and central China, on the other
hand, is most prolific; and in addition, blooms from June to October. It
will be seen that crosses of these two species may produce valuable
breeding stock." As a result of this cross, made in 1934, we obtained
seven nuts, and from these nuts we have today, nineteen years later,
four trees, three of which have shown marked blight resistance. One of
these three is much larger, partaking more in its stature and form of
the character of its Chinese parent, and in contrast to the latter,
bears burs and nuts in profusion, usually clustered at the ends of the
branches. (Fig. 2). The nuts are small but of good flavor. It is a good
nut tree, not suitable for timber. However, as we stated in our 1951-2
report, it is subject to considerable twig blight, caused by the attacks
of the weak parasite, _Cryptodiaporthe castanea_ (Tul.) Wehmeyer, and
this is due apparently to the influence of its tender parent, the Seguin
chestnut, which habitually dies back in the winter. The parasite easily
enters the dying ends of the twigs. We should like to see this tree
tried out in a warmer climate--Georgia, Florida, Alabama, etc. Possibly
it might prove adaptable to a southern European environment.[5]

[5] Systematic descriptions of this and other valuable chestnut hybrids
are being prepared for publication.

Pollen Receptivity of Female Flowers

Chestnut is monecious. The flowers are borne on the present year's
growth in long catkins. These are of two distinct types; near the base
of the flowering branch they consist of male flowers only. The catkins
near the apex, on the other hand, are bisexual; pistillate flowers are
found, solitary or in clusters of two or three, near the base of this
type of catkin. The remainder of the catkin bears male flowers similar
to those on the all-male catkins.

The unisexual male catkins are the first to start flowering and not
until two to three weeks later will the male flowers of the bisexual
catkins be in full bloom. Normally, the pistillate flowers will reach
full development sometime between these two periods of pollen shedding.

_The Length of the Receptivity Period._--During the summer of 1953 an
experiment was conducted to determine more definitely when the pistils
became re