I had Japanese knotweed in my garden and got rid of it by cutting it down and then spraying the regrowth at 6-12 inches with glyphosate, as mentioned. I think that I had to repeat this about four times over two years. If you can get it use the commercial/farmers version of Roundup and not the Roundu...

Thank you for your replies. I have invested in a copy of Thomas & Lewington but they showed the male dark but still with vague spots.

John

Can a Ringlet have very dark upper wings with no markings apart from the white border, or am I looking at something else? There were a pair of them in my field some 100 yards from an active group of easy to identify Ringlets. They wouldn't stay around for a photo but I'll try again tomorrow.

John

Thank you for proving my suspicion that I can't tell a moth from a butterfly.

Another newcomer who can't tell a butterfly from a moth with a couple of problem butterflies?