518 COMPOSITAE 
3. Cirsium undulatum (Nutt.) Spreng. Wavy-leaved Thistle. Fig. 5904. 
tess aapated Nutt. Gen. 2: 130. 1818. 
irstum undulatum Spreng. Syst. 3: 374. 1826. 
Pe os BS var. megacephalus A. Gray, Proc. Amer. Acad. 10: 42. 1874. 
Perennial herb with a sant Janregtis and with fine, spreading, lateral roots from which ne 
rosettes aod shoots arise, the rown generally unbra the stems usually simple iol 
solitary at the base, sasiteulately brasichitie above or dearly Sate: stems erect, 3-7.5 dm. tall, 
rather stout, somewhat angled to solicit rather jb “apd eve nly white- ‘Janate. Earliest 
inu 
to a large, many-leaved rosette that develops throu wo or perhaps three seasons and that may 
have disappeared before the aerial stem develops; rosette-leaves 3-7 dm. long, up to 1.2 dm. wide, 
oblongish or sometimes narrowly elongate, pinnately parted or a ogi ate deltorts i or 5 aise ar- ee 
segments, the visions and lobes tipped by short spines, the blade rowed bel o a lon 
artaceou mi y 
ciliolate or sometimes even a little aay opr mre las generally Pr ero er- pecs or purplish, 
rarely white, the tube 1.5—2 cm. long, the thro t 8-12 mm. long, the lobes 6-8 mm. long; achenes 
brown, narrowly Sitdneiat is tniciate, little acres 8 mm. long, 2.5 mm. wide; pappus white, 
2-3 cm. long. 
Rocky, sandy, or clayey soil of open rolling hills or bluffs and slopes of volcanic or granitic roskes Arid 
‘Scausiticn "rong: east of the Cascade Mountains, British Columbia south to northern Oregon; east to the entral 
United States, and south to Arizona; introduced in southern Cabiornia and _perhaps elsewhere. Type lbcality: 
“On the calcareous islands of Lake Agen and on the sie ns of Upper Louisiana.” June—Sep 
.,, Cirsium ochrocéntrum A. Gray, Mem. Amer. Aca . IT. 4: 110. 1849. Very spiny plants th om thick, cord- 
with a co: ose tip 
corollas red or white; anther-tips subulate. Occurring as a weedy introduction in souther n California; ee the: 
in the western United States from Arizona east to Texas ihr Nebraska. Type locality? mountainsides around 
Santa Fe, Santa Fe County, New Mexico. May—Oct 
4. Cirsium brevifolium mete ig: Thistle. Fig. 5905. 
lium Nutt. Trans. Amer. Phil. Soc. IT. 7: 1841. 
Cirsium piste Piper in Piper & Beattie, Fl. S.E. wie. val 1914. 
Plants perennial, spreading by slender — roots from which new plants arise, the new 
plants elongate taproots, the stems solitary or few in a cluster ; stems erect, 0.3-1 m. 
tall, slender or rather thi ites and hollow, panne bat angled, thinly to densely arachnoid-tomentose. 
Leaves mostly pion ms, cage elow, green and thinly arachnoid or gla tere ithe. 
i d 
ppres: ept at th 
phyllaries long-attenuate into a spreadin 
ne 
ob! 1 the 
spreading, ivory- — sometimes slightly tinged = | gs or lavender , the co tube 9-13 
ong, the throat 8-11 mm. “sme the lobes 5-8 mm. long; achenes obionts mm. long, 
2'min. wid igs liga “in except for the upper part Bena is buff; pappus sordid or nearly white, 
Deep oe — hills and meadows or loose rocky soil of cuts and canyonsides, Arid Transition Zone; ¢ 
of the Cascade wir Hes gg a central Washi ngton ponte to central (perhaps southern?) Oregon east to Tasho. 
Type meng “Tn on Rocks Mountain plains.” June—Oct. 
eee © ta ae grows with C. undulatum in Washington and with C. utahense in Oregon, suspected 
hybrids betw: 
5. Cirsium aye das (Henderson) J. T. Howell. Ashland Thistle. Fig. 5906. 
0 
Cirsium undulat um Henderson a Torrey Club 27: 348. 
Carduus ciliata Hdl ae 1:5. 190 
