This is a red-stemmed filaree. The internet tells me that it is: “The most widespread and one of the earliest plant introductions into California. It was found in adobe bricks of Mission San Antonio Padua and several others from 1771.”

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This is a red-stemmed filaree. The internet tells me that it is: “The most widespread and one of the earliest plant introductions into California. It was found in adobe bricks of Mission San Antonio Padua and several others from 1771.”