California Native Plant Society On-line Inventory - 6th edition, 2001. ...A synonym of T. variegatum (phase 4) in The Jepson Manual, but appears to be distinct...
Correspondence 1 indicates that for The Jepson Manual [Ed. 2] Trifolium variegatum phase 4 of The Jepson Manual [Ed. 1] is to be treated as Trifolium polyodon Greene, with no explanation for the change given.