On Mon, 27 Aug 2012 18:35:59 +0100, Fuschia
wrote:

We are told not to put Japanese knotweed in our green waste, which
seems to suggest that the composting method is not thorough.

The reason is more likely to be that it's illegal.

Last year someone deposited some JK at the local tip. The skip in
question was quarantined as they couldn't send it off site (again
illegal) to be composted and the lot was removed by a specialist
contractor as they couldn't reliably separate all the knotweed from
the other green waste.

Cheers, Jake
=======================================
Urgling from the East End of Swansea Bay where sometimes
it's raining and sometimes it's not.