Mystery Plant...

A few days ago I wrote about a native plant that I have not been able to identify, a plant with the interesting ability to suppress mustard and filaree.  One reader wrote to offer assistance with identification, and another wrote asking for photos.  So here are a couple of (not particularly good!) photos.

The first one (above right) shows a dense patch of these plants in an area where I have not yet mowed.  Those plants are about 30 inches tall.  In this area there isn't a single weed of any kind.  Before I encouraged this mystery plant, this area was a dense bed of mustard.

At left is a closeup of these same plants.  You can see that they're more stem than leaves, a common desert adaptation. 

In most of my yard I've mowed these down to just an inch and a half high.  So far, they appear to be enduring this abuse just fine.  We'll see for sure in the next couple of months, as I know from past experience that these will continue to grow slowly in the summer months (though my past experience is with unmowed plants!).

Any help on identification would be greatly appreciated.  If nothing else, I'll be able to put the correct name on the shrine I'm planning to erect to this weed-snuffer!!!