Herse convolvuli

[Matthew Smith]

Message text written by INTERNET:Martin.Askey at btinternet.com
>seeking herse convolvuli for biological control of bindweed. any sources
please for larvae.

Martin
<

Martin

Not meaning to be negative, I don't think you are going to be able to solve
you bindweed problem using biological controll, not in the UK anyway.  If
you try to use Convolvulus Hawk moth (Agrius convolvuli) you will have
similar problems to those you would have if you used the Four-spotted (Tyta
luctuosa).

In the UK A.convolvuli is a migrant species, adults arrive from the
continent in late summer and may lay eggs, but they are very infrequently
recorded.  The pupae from these late summer larvae do not survive the
winter in the UK, so it would be impossible to establish a population
outdoors to control your bindweed.  You could try overwintering some pupae
yourself and seeing if you can get some eggs from the females in spring. 
If you put these larvae on your bindweed they might make some impact, but I
would think that applying too many larvae would mean that the majority
would wander off to find an uncrowded food source.  The larvae prefer the
large white-flowered Hedge Bindweed (Calystegia sepium).  The larvae do get
big and do eat a lot of bindweed but, as I'm sure you realise, bindweed is
almost unkillable.  Removing some of the leaves wont hurt it.  Without
getting rid of the roots, it will just come back again (and again as my
garden will testify), and will probably be fully recovered by the time you
larvae have pupated and emerged as moths, ready for a second bash at the
plant.  If you dont want to use chemicals then digging is the only option.

The Amateur Entomologists Society Annual Exhibition is on next Saturday at
Kempton Park Racecourse, there are usually some larvae/pupae for sale at
this event.  (see: http://www.theaes.org).
Otherwise, try the Entomological LIvestock Group (ELG) (see:
http://www.pwbelg.clara.net/index.html),
though you are more likely to see larvae for sale in the spring.

Regards

Matt