Derris Substitute?

[Arch]

My Mum has a plum tree, and last year was scuppered by a plum sawfly. I looked up cures and they all suggest the application of Derris.

Apparently Derris is now illegal. Any ideas on what is a suitable substitute - chemical or brand name?

It's thanks to this pest we're not getting our Boxing Day plum crumble, so this is important!

[benborp]

This was asked on the edition of Gardeners' Question Time that was broadcast today. I didn't hear the end of the answer though. I assume it will be available on iplayer.

[Arch]

Yes, that's where she heard about it being illegal!

Mum only heard a suggestion to use a tar band to catch the larvae... But she was in the midst of preparing for a housefull of visitors, so maybe listening to iplayer to check will be a good idea.

[robbo6]

Yes, a tar band is one way, as is digging over the soil around the tree to allow birds to catch the grubs.
Pyrethrum is used for some pests that Derris was used for, but I can only speak for it's use on grape vines, check that whatever you use is licenced for use on plums. (Although a quick search shows that there is probably no problem.)