Good bugs v Bad weeds on G&S

[Jerra]

one year i noticed the whitefly had colonized a viburnum outside the door to the green house, on closer examination i spotted the parasitsed scales from the Ichneumon Wasp control we used inside had moved outside.

 

this was of course after being told the wasp would not survive outside

It depends surely on what is meant by survive outside. Drop me in the middle of a desert and come back a day or so later and I may have survived. The same with the wasp could it/did it survive the winter and become a permanent part of the habitat?

 

I suspect when you were told they couldn't survive outside they meant to live and become established after a winter.

[PaulG]

It is right to be concerned about non-native species because climatic and other differences could mean that anything imported as a predator could become an invasive species. We probably will make the occasional mistake but in the context of cutting down the use of chemical pesticides it's probably worth the risk.

The North American weevil they are using is not classed as a non-native species.

 

It has been present in the UK for around 100 years - it was first detected in 1921.

 

DEFRA consider it to be "ordinarily resident", with no licensing restrictions.

 

There's some information about Azolla control using these weevils here:

 

http://www.cabi.org/projects/project/2709

[YamYam]

Weevils are no problem, just release a few cane toads to eat them.

 

 

Starting to remind me of 'the little old lady who swallowed a fly'

[mango]

The North American weevil they are using is not classed as a non-native species.

 

It has been present in the UK for around 100 years - it was first detected in 1921.

 

DEFRA consider it to be "ordinarily resident", with no licensing restrictions.

 

There's some information about Azolla control using these weevils here:

 

http://www.cabi.org/projects/project/2709

Let's hope that biological control is the answer to the invasive species in and around the waterways.