] wrote in message
...
Aphids can be like that. I have seen a row of broadbeans with some
plants badly infested while others a few feet away are only lightly
infested. If it is woolly aphid the best bet is something containing
a systemic aphicide such as Pirimicarb. It kills only aphids and not
bees etc. Aphids suck the sap and a systemic should kill them even
when their 'wool' prevents the spray making direct contact.

Is there a possibility of an organic solution at all? Like wiping the stems
with surgical spirit or something like that?
If not, I'll have to bite the bullet with a systemic aphicide.
I appreciate your input, Tom. I'm fairly sure you are right that it's
woolly aphid - I've never seen it before.

Tina