In article
Kay Lancaster writes:
["Followup-To:" header set to rec.gardens.]
On Wed, 26 Jun 2013 04:42:03 +0000 (UTC), Danny D. wrote:

I think it's some kind of horrid thistle all over my fescue lawn:
http://www3.picturepush.com/photo/a/...g/13411201.jpg

Try pulling one up... you may find they're attached to an underground
root and stolon system, in which case you may be dealing with
Canada thistle, Cirsium arvense, a noxious weed* in California, and
you might want to consider some minor chemical warfare, as fragments of
the underground portions of the plants about 3/8" long can start new
ones, as can all the seeds. http://www.cal-ipc.org/ip/management...mber=182.ph p

His plant's flowers looked too large for Canada thistle, at least
based on the ones I deal with (in Ohio). But I suppose that might
vary with growing conditions.

They can basically take over an area in a few years.

I made the mistake of ignoring them. They got well established in
the area that I just returned to a vegetable garden this year. I
tilled, which broke up the underground network (or most of it), but
I still have to get the survivors before they have a chance to
reestablish it.

But till & trowel isn't an attractive solution if they are in the
lawn.

I control it here in my Oregon yard with heading the flowers**
as soon as I see them, and spot applications of glyphosate on
established plants in the fall. Heading has to be done vigilantly--
at least once a week.

I never had much success with glyphosate. (I keep it on hand for
poison ivy and a couple other special cases.) I attributed that to
the root network.

One end of the yard is a garden with Canada thistle, the other end
is lawn with Bermuda grass (the undesirable sort).

I have a way of attracting invasive weeds, I suppose.

--
Drew Lawson | I told them we had learned to change
| our swordblades into plows.
| I told them they should learn from us
| what should I tell them now?