Prairie Flora 369 



that species has been united with Artemisia ludoviciana it will have 

 to be called by the latter name. Dalea alopecuroides, /ormerly Paro- 

 sela Dalea, is occasionally found cii river bottoms here. Polaniaia 

 trachysperma T. & G, seems to have been collected in the river valley 

 at Montevideo, although that location is somewhat outside of its range. 

 Polanisia graveolens Raf, is a very common plant on lake shores. 

 Acorus Calamus has been collected at Carlton lake, Montevideo, but 

 is very rare in this part of the state. Strophostyles pauciflora 

 (Benth) Wats., a rare leguminous plant here, is found at Big Stone 

 lake. The typical river valley thistle is Cirsium altissimun, some- 

 times growing to the height of seven or eight feet. In the Minnesota 

 river near Biw Stone lake therje has been collected Mryiophyllum spica 

 turn and M. verticillatum and they are doubtless common in suitable 

 locations throughout this part of the state. The common blazing-stars 

 of the river valleys are Liatri^. scariosa and L. pycnostachya, the 

 former growing on higher and dryer ground. The river valley sun- 

 flower is Helianthus grosse-serratus Willd., while the broad-leaved 

 species found near the edges of the timber is Helianthus tuderosus. 



In late summer Lobelia syphilitica is common in wet meadows. 

 The Lactucas are represented by L. canadensis, L. hirsuta, L. ludovic- 

 iana, and L. pulchella, the latter being quite common. L. scariola in- 

 tegrata is too common in gardens. Thlaspi arvense is spreading rap- 

 idly along railway embankments and promises to become a trouble- 

 some weed. What seems to be Spiranthes gracilis is frequently found 

 in wet meadows. Grindelia squarrosa is found at Montevideo near 

 the railroad track, and along the Stn.te line south of Gary. 



Among the fall asters of the river valleys may be mentioned. Aster 

 salicifolius and Aster lateriflorus growing on low ground. Aster laevis 

 is found on higher ground along the edges of timber, while Aster 

 novae-angliae, the most beautiful of asters, is found along spring 

 brooks. Boltonias are common in wet places and contribute much 

 to the beauty of the autumnal landscape. 



6. The Bluff Flora. 



It is along the bluffs of the river valleys that there is found the 

 greatest number of plants having a western range. The grass flora 

 resembles that of the upland prairie, including Andropogon scoparius, 

 Bouteloua curtipendula, Bouteloua oligostachya, Agropyron smithii, 

 Agropyron tenerum, Stipa spartea, Sporoholus heteroiepsis and Calamo- 

 vilfci longifolia. 



Among the early spring flowers may be noted Agoseris cuspidata 

 with flowers much like a dandelion. This genus has been called 

 Troximon and Nothocalais. One of the showiest bluff flowers is Pent- 

 stemon grandiflorus, but it is rather rare in this region. Pentstemon 

 gracilis has bt.en collected at Ortonville, and Penstemon albidus is plen- 

 tiful at Montevideo. Two other common bluff flowers are: Litho- 

 spermum angustifolium and L. canescens. Geum triflorum with its 

 purple calyx and long plumose styles is a very showy object in May 

 and early June. Another May flower on prairie knolls is Allium reti- 

 culatum. It is quite dwarf and has white flowers. Astragalus ad- 

 surgens forms dense caespitose masses on prairie knolls, its dense 



