London Rocket (Sisymbrium Irio)

I met a new plant.  The leaves design first caught my eyes, all jagged and deep lobed in a rosetta shape.  I thought they were dandelions.

But the yellow wispy yellow flowers that emerged later suggested otherwise.  

It is not wild arugula either. It is Sisymbrium Irio, known as London rocket. The confusion is wild arugula (diplotaxis tenuifolia) is referred to as rocket by some folks and Sisymbrium irio, also of the mustard family, is referred to as London rocket. While they come from the same brassicaceae family and share lots of similarities, they diverge in the appearance of the tiny yellow flowers. One is considered ‘wild arugula’ while the the other is considered an ‘edible weed’. 

Apparently they grow all over Arizona and desert areas in California.  Each plant harbors several thousand seeds and are considered invasive weeds.  They are hardy, having withstood the blistering cold wind, frost and snow.  But it is said that hot weather will bring their demise...until the winter season returns.  

They are taking over the yard.  I’m not sure whether they should all be pulled or let them be.  I see the bees buzzing about the flowers so I think they belong here till summer comes around.