's plantings of ~Corylus~ at Geneva, we may
get more information on varietal preferences. I find that exposed
foliage of ~C. americana~, the common wild hazel here, is sometimes fairly
heavily fed upon. I am holding up to the window a portion of a hazel
bush; you can see that the leaves along one side are skeletonized. It is
probable that the species, hybrids, and varieties of ~Corylus~ will show
the same marked variation in susceptibility that is shown in so many
other genera of plants.

Among the oaks, the pin oak, ~Quercus Palustris~, and the English oak, ~Q.
robur~, are commonly one-third defoliated while the common white and red
oaks are almost immune. Among the maples--to go farther afield from
nuts--the Norway, ~Acer platanoides~, and the Japanese, ~A. palmatum~, are
often severely injured, where the sugar maple, ~A. saccharum~, is only
lightly injured and the delicate-leaved red maple and silver maple, ~A.
rubrum~ and ~A. saccharinum~, remain untouched.

Since the Japanese beetle is here to stay, and to spread, these
differences are worth considering where plant materials are being
selected for new ornamental plantings. In our bulletin on Japanese
beetle (Cornell Extension Bulletin 770) we have to warn the reader that
planting chestnuts may bring him trouble with the Japanese beetle,
trouble which he would not have with flowering dogwood, ~Cornus florida~,
or the common lilacs, ~Syringa vulgaris~, which are immune to this pest.

It may be, however, that some of the chestnuts carry immunity factors.
In the U. S. Department of Agriculture Circular No. 547, published in
1940, "Feeding Habits of the Japanese Beetle," by I. M. Hawley and F. W.
Metzger, ~Castanea crenata~, the Japanese chestnut, is listed with beech
and chestnut oak as "generally lightly injured." I understand you
consider the nut of this species poor, but if resistance factors are in
the genus, there can be hope of finding or developing a chestnut
resistant to Japanese beetle.

We might be able to do with chestnuts what has been done with poplars.
The common poplars range from the Lombardy, ~Populus nigra italica~, which
is heavily damaged by the beetle, to the white, ~P. alba~, which is
immune. The forest geneticist, E. J. Schreiner, has written an article,
"Poplars can be bred to order," which appears on pages 153 to 157 in
"Trees," the Yearbook of Agriculture for 1949, published by the U. S.
Department of Agriculture. Schreiner provides an inte