In article ,
Emery Davis wrote:
On Wed, 28 May 2014 11:27:10 +0100, Martin Brown wrote:

I mean regular hogweed, not the giant variety thank goodness.

That's not a major problem, despite the tabloid hysteria. Yes, it's
a thug.

It should be good enough to hit it with any broadleaf specific herbicide
assuming it is in grass or glyphosate if you don't mind a bit of
collateral damage and scythe it down in flower before it sets seed.

I haven't found glyphosate to be effective, possibly I've been a little
late in the season. Do you have a particular boradleaf herbicide to
recommend? (If it kills dock and too, that would be just fine...)

The normal problem with using glyphosate is following the instructions
on the bottle :-(

It works better if you use it at HALF strength, and possibly repeat
it a few weeks later (in cool weather). And, yes, start as soon as
there is enough foliage.

Glyphosate is actually grass-specific, and will kill grass at levels
that leave most other plants alive. The only one more effective that
I know of is brushwood killer - but even that doesn't kill established
trees and shrubs in one go.


Regards,
Nick Maclaren.