few weeds; thus weed control should be aimed only at carefully 

 chosen targets. 



Lake Elmo State Park 



The native flora at this park in the greater Billings 

 area has been almost entirely replaced by introduced and weedy 

 species, in fact it is difficult to determine what the 

 original vegetation was like. Much of the area has been 

 planted with pasture forbs and grasses including Agropyron 

 cristatum (crested wheatgrass) , Bromus inermis (smooth brome) , 

 Medicago satlva (alfalfa) , Melilotus alba (sweetclover) and 

 Trifolium pratense (red clover) . Weeds in the park include 

 Centaurea maculosa (spotted knapweed) , Centaurea repens 

 (Russian knapweed) , Cirsium airvense (Canada thistle) , 

 Convulvulus arvensis (field bindweed) , Glycyrrhiza lepidota 

 (licorice) , Kochia scoparia (kochia) and Salsola kali 

 (tumbleweed) . Native taxa are mostly isolated, not part of 

 intact systems. Native Acer negundo (boxelder) and Populus 

 deltoides (cottonwood) grow along the lakeshore along with 

 exotic woody species like Eleagnus angustifolia (Russian 

 olive) and Malus domestica (apple) . Wet alkaline flats are 

 occupied by a mixture of native and exotic species including 

 Aster falcatus (creeping white prairie aster) , Chenopodium 

 spp. (goosefoots) , Hordeum jubatum (foxtail barley) , Scirpus 

 spp. (bullrushes) , Tamarisk chinsnsis (salt cedar) , and Typha 

 latifolia (cattails) . The predominance of members of the 

 Chenopodiaceae (goosefoot family) and other salt tolerant 

 plants are evidence of alkaline soils. No MPSSC are likely to 

 inhabit the park. 



Manuel Lisa Fishing Access Site 



Vegetation at this small area along the Bighorn River at 

 its confluence with the Yellowstone consists of floodplain 

 woodlands and mudflats, and disturbed sagebrush grasslands. 

 The woods are dominated by cottonwoods (Populus deltoides) and 

 Russian olive (Eleagnus angustifolia) , and have an understory 

 of weeds and disturbed sand. The mudflats are dominated by 

 canary reedgrass (Phalaris arundinaceae) , bullrushes (Scirpus 

 sp.), and blue vervain (Verbena hastata) . The sagebrush 

 grassland, dominated by big sagebrush (Artemesia tridentata) 

 and blue grama (Bouteloua gracilis) has a diversity of native 

 herbs but is also very weedy. Exotic species at this site 

 include smooth brome (Bromus inermis) , Russian knapweed 

 Centaurea repens) , Canada thistle (Cirsium arvense) , foxtail 

 barley (Hordeum jubatum) , kochia (Kochia scoparia) , alfalfa 

 (Medicago sativa) , sweetclovers (Melilotus alba and M. 

 officinale) , and salt cedar (Tamarisk chinensis) . There is 

 little potential here for occurrences of MPSSC. 



Natural Bridge State Park 



Vegetation at this park is quite diverse, relatively 

 pristine, and unlike that of any of the other sites visited 



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