CH1CORIACEAE (CHICORY FAMILY) 



1 CHIC6RIUM CHICORY. (C. intybus.) 



2 LAPSANA... NIPPLEWORT. (L. communis.) 



3 ADOP6GON. 



i a Stem with 2-6 heads; stem leaves 1-3 



CYNTHIA. (A. virginicum.) 

 b Stem with i head ; stem leaves wanting 



DWARF DANDELION. (A. carolinianum.) 



4 LEONTODON FALL DANDELION. (L. autumnale.) 



5 PICRIS HAWKWEED PICRIS. (P. hleracioUes.) 



6 TRAGOP6GON. 



i a Flowers yellow GOAT'S BEARD. (T. pratensis.) 



b Flowers purple SALSIFY. (T. porrifblius.*) 



7 TARAXACUM. 



i a Outer bracts of involucre reflexed ; achenes greenish- 

 brown COMMON DANDELION. (T. taraxacum.) 



b Outer bracts of involucre ascending or spreading; 

 achenes reddish 



RED-SEEDED DANDELION. (T. erythrospermum.) 



8 S6NCHUS. 



1 a Bracts of involucre with glandular hairs; heads 1-2 



in. broad FIELD Sow THISTLE. (S. arvensis.) 



b Bracts of involucre not with glandular hairs; heads 



%-% in. broad 2 



2 a Basal lobes of the upper leaves pointed ; basal leaves 



pinnatifid COMMON Sow THISTLE. (S. oleraceus.) 



b Basal lobes of the upper leaves rounded ; basal leaves 

 lobed or pinnatifid 



SPINY-LEAVED Sow THISTLE. (S. dsper.) 



9 LACTUCA. 



1 a Leaves with spiny margin and with spiny midrib be- 



neath PRICKLY LETTUCE. (L. scaribla.) 



b Leaves not completely as in a 2 



2 a Flowers blue; pappus brown 



TALL BLUE LETTUCE. (L. spicata.) 

 b Flowers yellow ; pappus white 3 



3 a Basal leaves pinnatifid ; wild species 



WILD LETTUCE. (L canadensis.) 

 b Basal leaves not pinnatifid; cultivated for the leaves 



GARDEN LETTUCE. (L. satlva*) 

 10 CRfcPIS. 

 i a Heads %-% in. broad; principal bracts of involucre 



not hairy within SMOOTH HAWKSBEARD. (C. <virens.) 



b Heads 1-2 in. broad; principal bracts of involucre 



hairy within ROUGH HAWKSBEARD. (C. biennis.) 



n HIERACIUM. 



i a Flowering stem leafless or with 1-3 bract-like leaves. . 2 

 b Flowering stem with leaves 4 



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