The poisonous
Chlorophyllum molybdites is similar in appearance but is rare to absent in Washington. It differs in that the gills are greenish when mature and the spore deposit is greenish. The edible
Chlorophyllum brunneum differs in that the cap has brownish scales on a white background rather than on a brownish background and the stem exhibits a simple ring rather than a double-edged ring. The edible
Chlorophyllum rhacodes differs in that the cap has brownish scales on a white background rather than a brownish background.
See also
Coprinus comatus.