commutatus (silverberry) , and Rosa woodsii (rose) are 

 additional understory shrubs. Also alarmingly dominant in the 

 understory is Euphorbia esula (leafy spurge) , a bad, difficult 

 to control weed; special care should be taken so that control 

 measures do not harm the native woody vegetation. The gravel 

 bars and flats are dominated by Salix exigua (willow) , 

 Phalaris arundinaceae (canary reedgrass) , Rumex crispus (curly 

 dock) , and Polygonum amphibium (water smartweed) . The weedy 

 roadsides are dominated by introduced grasses, including 

 Bromus inermis (smooth brome) , B. tectorum (downy brome) , 

 Elymus repens (quackgrass) , Poa pratensis (Kentucky 

 bluegrass) , and Setaria viridis (foxtail) . Verbascum thapsus 

 (mullein) and Melilotus officinale (sweetclover) are two more 

 introduced species common along the road. The possibility of 

 MPSSC occurring at this site is remote. 



Captain Clark Fishing Access Site 



This is a very weedy bottomland site along the 

 Yellowstone River. The area is divided by fences and by a 

 slough into three sections. The area across the slough was 

 not accessed for this project, but from a distance seems to be 

 mostly cottonwoods and willow thickets. The two sections on 

 the road side of the slough are mostly meadows with some 

 cottonwoods and thickets. One section was heavily trampled 

 and grazed by cattle (illicitly ?) with little vegetation • 

 surviving except the dominant introduced forage Elymus 

 hispidus (intermediate wheatgrass) , which oddly was not 

 touched by livestock (perhaps it was over-mature for 

 palatability) , a native species of Symphoricarpos (snowberry) , 

 and the weeds Sisymbrium loeselii (tumble mustard) and Hordeum 

 jubatum (foxtail barley) . The heavily impacted thickets in 

 this grazed section are dominated by Salix exigua (willow) 

 with a vine understory of Vitis riparia (wild grape) and 

 introduced Solanum dulcamara (blue bindweed) . The ungrazed 

 meadows are dominated by a rank growth of weedy natives and 

 exotics including Cirsium arvense (Canada thistle) , Iva 

 xanthifolia (marsh elder) , Medicago sativa (alfalfa) , 

 Melilotus alba and M . officinale (sweetclovers) , and Verbascum 

 thapsus (mullein) . Except for the woodlands across the 

 slough, the native flora at this site is very limited and 

 there is little potential for occurrences of MPSSC (none have 

 been reported in Yellowstone county) . A weed management plan 

 is badly needed. Grazing does not seem compatible with 

 recreation, however, leasing the meadows for hay would be 

 acceptable, and may help reduce the weed problem. 



Chief Plenty Coups State Park 



The vegetation of this park includes native habitats, hay 

 fields, and areas managed as mowed turf. The native habitat 

 consists of wet bottomlands and dry, rocky uplands. The 

 bottomlands are dominated by cottonwoods {Populus deltoides 

 and P. balsamifera) , box elder {Acer negundo) , and shrubs 



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