Rick McGreal wrote:
"William Tasso" wrote in
:

I'm afraid this will become an obsession for you but whatever happens
do not under any circumstance allow them to go to seed - you will
regret it.

What do you mean 'Go to seed'?

When the yellow heads die off and the white ones appear?
The ones that we used to call 'clocks' when I was young?

You got it - also known as faeries by some of the younger 'helpful'
gardeners round here as they blow them around the garden - aaaaargh.

Can I simply mow the heads off while waiting for my weedkiller to
work?

Not unless you are 100% sure the seed is sterile (I don't know how you would
ensure that). I'm inclined to pick the heads off when they're at the bud
stage. It's an every-day morning task once you've declared war on them.

In any event, have fun.
--
William Tasso