"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?

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