mystery plant identified
Aha. It turns out the mystery plant that I thought at first might be a form of bluebonnet may be “wild alfalfa.” I sent a picture to the Lady Bird Johnson Wildflower Center in Austin and got this reply.
Our expert, Joe Marcus, believes your “bluebonnets” are really wild alfalfa or scurfy pea, Psoralidium tenuiflorium. […]