In article ,
Stewart Robert Hinsley wrote:

I have two hazels for many years, and never had a nut. Do they come in
male/female form? If so I must have two boys :-(-

Yes.

This needs clarification. The flowers come in male and female forms -
catkins are male, the females are little red tufts - but both male and
female flowers are on the same tree.

I don't know the cause, but in my experience a lot of hazels don't
fruit.

My memory was (partly) at fault. Clapham, Tutin and Warburg say
that the pistil and stamens may or may not mature at the same
time, so some clones of hazel will be self-sterile. Even in a
mixture, some may not fruit if the pistil matures at a time when
there are no mature anthers in the vicinity.


Regards,
Nick Maclaren.