AUTHORS NOTE: I have not seen this plant at Mather Field. 

Lepidium latipes var. l.

Brassicaceae Family (Mustard)

Distinguishing Characteristics

• Fruit densely clustered within the basal rosette of leaves.

Habitat(s)

• Alkali grassland. 

Additional Information

• Native. Endemic to California and Baja California.
   
• Flowering time: February - May.
   
• Additional images from CalPhotos.
   
• Treatment from Jepson Manual.