This originated as a 1930 selection made by the late Dr. G. A.
Zimmerman, Linglestown, Penna. Very few sound nuts of Zimmerman have
ever been produced, for soon after the first crop the identity of the
tree became lost and eventually it was destroyed together with others in
an overgrown nursery row where it stood. In one known case where there
are grafted trees of bearing age, the nuts are regularly destroyed by
weevils. Such nuts as have been seen by the writer have been of a dull
brown color and have had surface down only about the apex.
The Zimmerman was first catalogued in 1938-39 by Dr. Smith. It is
probable that as many trees of this variety have been sold and planted
as of any one variety but performance records are difficult to obtain.