"Victoria Clare" wrote in message
.207...
"Tumbleweed" wrote in
:


I don't know of any detailed tests. Do you? So far, we seem to
be
working with anecdotal evidence on both sides of the discussion.

tests for what? Its a fact that greenfly populations are not
controlled by predators. Thet grow, thrive and survive untol the
cold
weather comes.

And your source is? I'm not being awkward, I want to know! How do
you
know for a fact that greenfly populations are not controlled by
predators?

A variety of factors makes the difference. randomness for one,
nature
is like that. next year I might not have any and you might have
lots .
Also, do you spray with water or soap or pinch them off when you
see
them? I dont, maybe I should, as killing one greenfly at the start
will prevent a huge number a few weeks later. But is that
ecological?
is killing them by a different means any better?

No, I don't usually bother here (I did in Cheshire or things went
crispy!). But why would human 'predation' make a difference if bird
predation doesn't?

It is a fact that bird predation is almost negligible. I have for
years successfully encouraged a healthily mixed population of various
garden birds, including insect eaters, of course.
That does not appear to have given me any marked protection against
this, that and the other sucking insects.
Human predation is a different matter. We are beings with vastly
improved intelligence compared with birds, we know what we wish to
eradicate and we know what murderous methods to apply to achieve our
goal. And when we have killed off every greenfly, we don't go hungry,
since they are not a food source for us.

Most of the plants I'm growing now, I was also growing in cheshire.

Plants that were severely affected by aphids in Cheshire include
rose
'LD Braithwaite' & 'New Dawn', and several varieties of honeysuckle.
None are afflicted with more than the odd bug here.

Basil was a problem at both locations, but then I grow it on the
windowsill inside.

Here, cherry trees seem less prone to blackfly, though it is still
an
issue.

Franz