Field Key to Yellow-green Foliose Lichens

1        Lobes narrow (1-3 mm wide); found on acidic rocks Xanthoparmelia plittii and X. conspersa

 

–        Thallus lobes relatively broad (3-10 mm wide); substrate various …………………………. 2

2        Thallus isidiate; found on rock…………………………………….. Flavoparmelia baltimorensis

–        Thallus sorediate; occurence most often on trees………………………………………………….. 3

3        Soredia powdery, massed along upturned margins in thick lip-ahaped soralia; thallus lobes smooth above………………………………………………………………………………. Flavoparmelia soredica

–        Soredia granular, scattered across or concentrated in patches on the upper surface; lobes often wrinkled above………………………………………………………………………………. Flavoparmelia caperata