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Plants of Wisconsin

Vascular Plants

KEY to the WISCONSIN ASTERACEAE

 

Tribe 2. CICHORIEAE (LACTUCEAE) - chicory (lettuce) tribe

 

(Source: Johnson and Iltis, 1963; FNA, 2006;

edited by R. R. Kowal, 2007 February 2.)

 

1.   Pappus absent

................ LAPSANA - nipplewort.

 1.   Pappus present.

 

2.    Pappus of numerous simple hairlike (capillary) bristles only.

 

3.   Achenes flattened or compressed.

 

4.   Achenes not beaked, not enlarged at the tip; heads yellow with many florets (80 or more)         

........  SONCHUS - sow-thistle.

 

4.   Achenes beaked or unbeaked, but constricted below enlarged tip; heads yellow or blue, with relatively few florets (5‑56).

 

5.  Perennials, arising from adventitious shoots on deep roots, with aerial shoot terminating an underground vertical stem (3-12+ cm long) , roughly uniform in diameter and bearing adventitious roots; heads large and showy, 2-3 cm broad, violet-blue, with 15-50 florets and involucres 13‑20 mm long; achenes with a short (< 2 mm long) , stout beak; rare adventive  

................ MULGEDIUM - blue lettuce.

 

5.  Annuals or biennials, with a relatively shallow, tapering tap root (sometimes obscured by lateral roots arising near base of stem); heads mostly smaller and not showy; fresh corollas yellow or whitish, IF blue, involucres < 13 mm long OR achenes with a long, filiform beak [Caution: corollas often dry to a different color]  

................  LACTUCA - wild lettuce.

 

3.    Achenes cylindrical, fusiform or terete, not flattened.

 

6.  Plants scapose; achenes beaked, or tapered and the beak lacking; pappus white; phyllaries in more than one series.

 

7.  Achenes tuberculate-muricate above with a long filiform beak; scapes hollow; leaves variously runcinate-pinnatifid  

................ TARAXACUM - dandelion.

 

7.  Achenes not tuberculate-muricate above, slightly tapered, but not beaked; scapes solid; leaves grasslike, the margins pubescent  

................ NOTHOCALAIS - prairie dandelion.

 

6.  Stems branched or unbranched and leafy or subscapose; achenes truncate or tapered, rarely short-beaked; pappus pale yellow, red-brown, tannish or white; phyllaries uni‑ or biseriate.

 

8.  Annuals or biennials with well developed, usually pinnatifid basal leaves; inflorescences open corymbs or panicles of yellow campanulate heads; pappus white; main phyllaries uniseriate  

................ CREPIS - hawk's-beard.

 

8.  Perennials; cauline leaves lanceolate to palmately lobed, or unlobed and dentate to entire; inflorescences branched racemes, panicles of cylindrical drooping heads, or corymbs with erect campanulate heads; pappus tawny to brown, not pure snowy white; main phyllaries biseriate.

 

9.   Leaves lanceolate to palmately lobed; heads cylindrical, nodding; corolla pink, purplish to yellow or white; pappus pale yellow to red-brown; plants sometimes tomentose, not glandular       

................ PRENANTHES - white-lettuce.

 

9.   Leaves spatulate to oblanceolate, not lobed; heads campanulate, erect; corolla yellow to red-orange; pappus tannish; plants usually glandular-pubescent       

................ HIERACIUM - hawkweed.

 

2.    Pappus otherwise (plumose bristles, scales, scales mixed with bristles, or a ring of numerous minute bristles).

 

10.  Pappus of plumose (feathery) bristles only.

 

11.  Plants leafy stemmed, branched, not scaly-bracted above; leaves cauline, grasslike         

................ TRAGOPOGON - goat's-beard.

 

11.   Plants scapose, scaly bracted above; leaves basal, coarsely dentate

 

12.  Inner and outer achenes uniform, not slender-beaked; receptacle naked       

................ LEONTODON - hawkbit.

 

12.  Inner achenes with long, slender beaks; receptacle chaffy       

................ HYPOCHAERIS - cat's-ear.

 

10.   Pappus of scales and/or bristles (sometimes minute).

 

13.  Pappus of 5 to numerous outer scales alternating with 5 to numerous scabrous hairs; plants scapose or sub-scapose, branched or not branched; corolla yellow         

................ KRIGIA - dwarf-dandelion.

 

13.  Pappus a ring of numerous minute (# 0.2 mm) scales or bristles; plants profusely branched; corolla blue, rarely pink or white         

................ CICHORIUM - chicory.

 

 

CICHORIUM - chicory

 

(s = 2x; x = 9)

 

..............  C. Intybus - chicory, blue sailors.

 

 

CREPIS - hawk's-beard

 

(Very rare waif: C. foetida - stinking hawk's-beard)

 

1.   Achenes distinctly slender-beaked; rare waif (s = 2x; x = 4)

 ................ C. setosa - bristly hawk's-beard.

 

1.   Achenes narrowed toward the top but scarcely beaked.

 

2.  Ligules yellow; inner surface of inner series of bracts microscopically appressed-puberulent; locally common (s = 2x; x = 4)

................ C. tectorum - narrow-leaved hawk's-beard.

 

2.  Ligules yellow, minutely tipped with red; inner surface of inner series of bracts glabrous; rare adventive (s = 2x; x = 3)

................ C. capillaris - smooth hawk's-beard.

 

 

HIERACIUM - hawkweed

 

(s = 2x, 3x [most apomicts]; x = 9)

 

(Hybrids between H. scabrum & H. umbellatum are not uncommon.

Rare adventive: H. murorum - wall hawkweed.  Not noted for WI & MN in FNA (2006).

 

1.   Plants scapose; leaves clustered at base, linear to spatulate or oblanceolate, sessile, pilose or glabrous, entire; heads yellow or red-orange; hairs less than 1 cm long or absent; introduced weeds.

 

2.  Scapes 0.4-4.5 dm tall, with 1 or rarely 2 or 3 heads; leaves pale beneath with close minute tomentum; extremely rare adventive .

................ H. Pilosella - mouse-ear hawkweed.

 

2.  Scapes (1‑) 2-10 dm tall with 7 to many heads; leaves with longer hairs or glabrous beneath. 

3. Florets bright red-orange; involucre densely covered with black-glandular and eglandular hairs; leaves spatulate to oblanceolate, with rusty-red pubescence; stolons present .

................ H. aurantiacum - orange hawkweed, devil's paintbrush.

 

3.    Florets yellow; leaves oblanceolate to spatulate.

 

4.  Leaves narrowly oblanceolate to spatulate, essentially glabrous; stolons lacking, short rhizomes present; peduncles minutely white-stellate         

................ H. piloselloides (H. florentinum) - glaucous king-devil.

 

4.  Leaves oblanceolate with tawny-white hairs on both surfaces; stolons erect or arching with abundant fine pubescence, rhizomes lacking or inconspicuous; peduncles glandular hirsute         

................ H. caespitosum (H. pratense) - yellow king-devil.

 

1.   Plants not scapose; leaves not clustered at base, OR, if so, then plants with abundant hairs 7‑20 mm long; leaves lanceolate to elliptic or spatulate, petioled or sessile-clasping, pilose to glabrous, the margins dentate to denticulate or subentire; heads yellow; rhizomes and stolons lacking [except H. Lachenallii (H. vulgatum)]; North American natives [except H. Lachenallii (H. vulgatum)].

 

5.  Leaves chiefly basal, abruptly reduced upward; plants, except the inflorescence, densely long-pilose, the hairs (7‑) 10‑20 mm long; peduncles with yellow-orange gland-tipped hairs; prairies, S and central Wisconsin

................ H. longipilum - long-haired or prairie hawkweed.

 

5.  Leaves often cauline; plants with hairs to 3 mm long or glabrous; peduncles glabrous, scabrous, stellate or appressed-pubescent, sometimes glandular.

 

6.  Leaves broadly elliptic, tapering to long and villous petioles, coarsely dentate; involucres 6‑8 mm long, the hairs stellate; stem glabrous [or hairy the length]; very rare adventive .

................ H. Lachenallii (H. vulgatum) - European hawkweed.

 

6.  Leaves various, tapering to shorter petioles or sessile, toothed to subentire; involucres 5‑13 mm long, glabrous to glandular; stem glabrous or hairy; common.

 

7.  Leaves spatulate, the lower petioled, the upper sessile, subentire; involucres (and peduncles) black-glandular, 5‑8 mm long; stem setose         

................ H. scabrum - sticky hawkweed.

 

7.  Leaves lanceolate to oblanceolate, sessile, toothed; involucres (and peduncles) rarely glandular, 8‑13 mm long; stem glabrous to villous-hispid or setose below         

................ H. umbellatum (H. Kalmii, H. scabriusculum) - northern hawkweed.

 

 

HYPOCHAERIS - cat's-ear

 

(s = 2x; x = 4)

 

................ H. radicata - spotted cat's-ear.

 

 

   KRIGIA - dwarf-dandelion

 

1.   Plants annual; achene conical; pappus of 5 outer scales alternating with 5 inner scabrous hairs; scape leafless; rare, S Wisconsin (s = 2x, 4x; x = 5)

................ K. virginica - Virginia dwarf-dandelion.

 

1.   Plants perennial; achene cylindrical; pappus of more numerous scales and scabrous hairs; scape bearing 1‑2 reduced sessile leaves; peduncles glabrous or glandular; common throughout (s = 2x, 4x; x = 5)

................ K. biflora - orange dwarf-dandelion.

 

 

LACTUCA - lettuce

 

(x = 9 & 17)

 

1.   Achenes with short stout beak or beak lacking; at least the lower leaves deeply lobed, petiolate or sessile, but if sessile the bases not sagittate-clasping; corolla bluish to whitish; tall woodland species.

 

2. Pappus white; leaves lyrately lobed, petioled; florets bluish; S Wisconsin (s = 2x; x = 17)

................ L. floridana - woodland or blue lettuce.

 

2. Pappus brown or tawny, never white; leaves sessile, the lower lobed, the upper entire; florets very pale bluish to ivory or whitish, inconspicuous; common throughout  (s = 2x; x = 17) .

................ L. biennis - woodland or tall blue lettuce.

 

1.   Achenes with distinct filiform beak; leaves variously lobed or entire, petiolate or sessile, but if sessile the bases sagittate-clasping; corollas yellow (sometimes aging or drying to bluish).

 

3.    Body of achenes with short white hispid hairs near summit; leaves with margins and midribs spinulose; common weed  (s = 2x; x = 9)

................ L. serriola - prickly lettuce.

 

3.    Body of achenes lacking hairs near summit; leaves not spinulose (except in L. ludoviciana, which has involucres longer than 15 mm).

 

4. Achenes (including beak) 4.5‑6.5 mm long; involucre 10‑15 mm long; leaves lobed or the upper unlobed, the margins dentate to entire; corollas yellow; very common (s = 2x; x = 17) .

................ L. canadensis - tall wild lettuce.

 

4. Achenes (including beak) 7‑10 mm long; involucre 15‑23 mm long; leaves lobed to dentate, pronouncedly glaucous and rather thick-textured, spinulose on margin and midrib beneath; corollas violet-bluish or yellow; prairies (s = 2x; x = 17) .

................ L. ludoviciana - prairie lettuce.

 

 

LAPSANA - nipplewort

 

(s = 2x; x = 6, 7, 8)

 

........  L. communis - nipplewort

 

 

   LEONTODON - hawkbit

 

1.   Scape hairy-bracted above; heads usually several, erect before anthesis; pappus of plumose bristles in all florets (s = 2x, 4x; x = 6)

............  L. autumnalis - fall-dandelion.

 

1.   Scape naked; heads solitary, nodding before anthesis; pappus of marginal flowers reduced to a crown of short scales (s = 2x; x = 4)

............  L. taraxicoides subsp. saxatilis (L. taraxicoides) - little hawk's-bit.

 

 

      MULGEDIUM - blue lettuce

 

(s = 2x; x = 9)

 

........  M. (Lactuca) pulchellum (L. tatarica subsp. pulchella) - showy blue lettuce.

 

NOTHOCALAIS

 

(s = 2x; x = 9)

 

........  N. cuspidata (Microseris cuspidata) - prairie or false dandelion.

 

 

PRENANTHES - white-lettuce

 

1.   Inflorescence an open panicle; leaves, at least the lower, long-petiolate, broadly ovate, deltoid to sagittate, or hastate.

 

2.  Basal leaves deeply palmately lobed; plants glabrous or nearly so; phyllaries purplish; pappus rich red-brown; very common throughout (s = 4x; x = 8)

................ P. alba - white-lettuce, rattlesnake root, lion's foot.

 

2.  Basal leaves coarsely and irregularly dentate; plants pubescent in inflorescence; phyllaries green; pappus pale yellow to brown; rare, S Wisconsin (s = 4x; x = 8)

................ P. crepidinea - midwestern white-lettuce.

1.   Inflorescence a dense, strict, elongate racemose panicle (thyrse); leaves, at least the lower, spatulate, the rounded blades gradually attenuate into the petiole; uncommon species of prairies.

 

3. Leaves of inflorescence with broad sessile auriculate bases; florets 8‑13 mm long, white to purplish; leaves and stem glabrous and glaucous except in the uppermost inflorescence; S and W Wisconsin (s = 2x; x = 8)

................ P. racemosa - glaucous white-lettuce.

 

3. Leaves of inflorescence lanceolate, with attenuate narrow bases; florets (8‑) 11‑15 (‑19) mm long, yellow; stem, at least the upper parts, and leaves scabrous, not glaucous; S Wisconsin (s = 2x; x = 8)

................ P. aspera - rough white-lettuce.

 

 

SONCHUS - sow-thistle

 

1. Perennials, strongly clonal by adventitious shoots on deep roots; heads large, the involucre 12‑20 mm long; leaf bases auriculate, more or less clasping the stem, the rounded auricles small and inconspicuous; achenes 5‑nerved; terminal leaf lobe elongate-triangular to oblong

...........  S. arvensis.

 

2.  Peduncles and involucre glandular (s = 6x; x = 9)

.........  subsp. arvensis - perennial sow-thistle.

 

2.  Peduncles and involucre glabrous (s = 4x; x = 9)

.........  subsp. uliginosus (var. glabrescens) - marsh sow-thistle.

 

1.   Annuals with elongate taproots; heads smaller, mostly 9‑12 (‑14) mm long; leaf bases auriculate-clasping, the acute or rounded auricles large and conspicuous; achenes 3‑ to 5‑nerved; terminal leaf lobe triangular.

 

3.  Auriculate leaf bases acute, the leaf margins sparsely prickly; upper leaf surface glaucous light green; achenes striate with 5 weak nerves; terminal leaf lobe sharply equilaterally triangular, cut nearly to midrib (s = 4x, 4x-4; x = 9)

................ S. oleraceus - common sow-thistle.

 

3.  Auriculate leaf bases rounded, the leaf margins abundantly spinulose-dentate; upper leaf surface dark green and lustrous, not glaucous; achenes 3‑nerved; leaves mostly unlobed, OR, if lobed, terminal leaf lobe broadly or irregularly triangular, the leaf cut about halfway to midrib (s = 2x; x = 9)

................ S. asper - prickly sow-thistle.