Anonymous, Calif. Fungi
Herbarium of the University of California. [1- ? 1425]

Cornell University, Plant Pathology Herbarium
Catalog #: CaliforniaF.01027
s.n.
Erysiphe polygoni DC.

USDA United States National Fungus Collections
Catalog #: BPI 948737
s.n.
Erysiphe polygoni DC.
United States, California

University of Wisconsin-Madison Herbarium
Catalog #: WIS-F-0015693
J. P. Tracy #8179 18 June 1927
Erysiphe polygoni DC.
United States, California, Humboldt, Near Petrolia

Field Museum of Natural History
Catalog #: C0285454F
efcebd25-20ca-46a9-94ab-c3fe36f87f75
J. P. Tracy #8179 18 June 1927
Erysiphe polygoni DC. DC.
U.S.A., California, Humboldt, Near Petrolia

Louisiana State University, Bernard Lowy Mycological Herbarium
Catalog #: LSU00155886
Joseph P. Tracy #8179 18 June 1927
Erysiphe polygoni DC.
United States, California, Humboldt, near Petrolia.

Michigan State University Herbarium
Catalog #: MSC0219017
Joseph P. Tracy #8179 18 June 1927
Erysiphe polygoni DC.
United States, California, Humboldt, Near Petrolia