Blackfly on Rhubarb!!!!

[NewbieGardenerRow]

First I found some on my flowering Nicola potatoes which are in bags so I snipped off the affected tips then squished any others then I went to check my broadies and not a single blackfly!!!!!!!!

Then I checked my bean fence and also all clear but right next to the bean fence is my rhubarb and all the younger leaves were absolutely covered in it and even more so the curled up new shoots.
I've picked it all and squished it all but should I leave it if any more arrives as I'm really not bothered about what it does to the rhubarb just as long as it is on there and staying off everything else?

Is rhubarb a blackfly sacrificial crop? Everyone I've spoken to says that they've never heard of blackfly getting on rhubarb before.
Thanks in advance.
Rowena

[rustylady]

Better on the rhubarb than on your beans. Try squirting them off with a high pressure spray or jet from a hose.

[planesailing]

They are on my Rhubard too, right next to the Broad Beans which have none! Bizarre!

[Lulubelle]

I've got blackfly on my rhubarb too and also lots of ants.