Is this why they're not dying ?!

My front yard has a nice, mostly square, grassy area surrounded by rocks.  There are 8 sprinkler heads that douse the lawn with ample amounts of water (when it doesn't rain enough and I need to use the sprinklers).  I fertilize and mow and trim the edges with my electric trimmer.

But the weeds (like Charlie Sheen) ... are ... winning.

I've hand-plucked weeds from the rocky areas MANY times in our 17 months at this house.  I have used a few different types of sprayable weed-killer to no avail.  I'm flat running out of options and feeling like it is a losing battle.

The other day, while weeding, I pulled out this one ...

I had Savannah (my almost 6-yr old) put her hand/arm on the table

so you can get an idea of the scale/size of this weed.

And now I think I know why nothing yet has worked. The above-ground part of the weed almost wasn't big enough to bother pulling out.  But once I carefully unearthed it I was SHOCKED !!!  Look at the length of those roots!  No wonder fertilizer and topical sprays aren't having ANY effect!

Feel free to comment with your tried and true suggestions for ridding my grass of these unsightly weeds.  I am truly open to any suggestions!

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