Any ideas on what this plant may b around Sacramento California
One of the Mallows.
Pull it while it is still small. They grow a long tap root that will break off and regrow if you do not remove it properly.
When they start growing the seed leaves (cotyledons) look like a pair of hearts. If you can hula-hoe them in this stage control is really easy.
Or let them go to seed, and harvest the green seed pods and use like okra =]
Some of those Mallows get 8' tall and wide here, so get rid of it while you can.