Why, please tell me why? Or, even how it happened!!!

Is this Japanese knotweed?
It was introduced to Britain in 1825 as an ornamental plant and for a while it was a must-have for any garden. It was a feature of many Victorian gardens throughout much of the 19th Century.
I do hope it isnt is it in your garden?

Yep. You are bang on the money on both counts there, Drc.

The plan is let it get a bit taller, cut it down leaving the hollow canes exposed and then filling them with Glyphosate at about 10X normal mix strength (of course taking full advantage of eating the bits we cut off before we poison it - apparently tastes like a cross between rhubarb and asparagus and makes a good pie).

After injecting the regrowth can then be sprayed later in the year ... repeating the injection/spraying process in subsequent years.

I'm going to put a photo guide together for publishing as I do it.

Oh poor you what a nightmare.

I can forgive it if the pie is good :)

Ha ha - just noticed that nobody likes this photo .... thank you :)