Four plant species of concern in this drainage are the wild 

 lily-of -the-valley (M aianth emum c anadense ) . New Jersey tea 

 (Ceanothus herbaceus^), few-flowered panic-grass (P anicu m 

 oligosanthes ), and leadplant (A morpha canescens ). The wild lily- 

 of-the-valley grows in riparian forests at low elevations along 

 the Little Missouri River and is listed as rare by the Montana 

 Rare Plants Project. The other three species grow in prairies and 

 open woodlands, and can be found throughout the adjacent Great 

 Plains states. Each of these species was collected only once and 

 none have been seen in the state in more than 30 years. 



Geologic Features 



Six percent of the Class I and II geologic feature sites 

 identified in the Montana Rivers Study, excluding type locations, 

 were found in these drainages. This low number of outstanding 

 sites in an area of this size can be partially explained in that 

 much of the area has not been examined as thoroughly by geologists 

 and paleontologists as central and western Montana. Without a 

 doubt, more thorough examination will reveal additional 

 outstanding sites. 



Southeastern Montana is not known for its lakes, but during 

 the Ice Age, a lobe of the continental ice sheet dammed the 

 Yellowstone River near Intake and created glacial Lake Glendive. 

 The water was backed up to just beyond present-day Miles City. 



Makoshika State Park near Glendive is an outstanding example 

 of "badlands," erosional features developed in fine-grained 

 sedimentary rocks such as shales and often devoid of vegetation. 

 Dendritic drainage patterns resembling a branching tree are often 

 associated with these areas. Another good example of badlands can 

 be found north of Terry. 



Sandstone bluffs that have weathered into "hoodoos" can be 

 seen at Medicine Rocks State Park north of Ekalaka. The cap rock 

 is more resistant to weathering than the material below it, 

 causing the hoodoos to stand some 30 to 40 feet above the 

 surrounding eroded landscape. These rock forms provide 

 opportunities for casual rock climbing. Fossils of small mammals 

 have been found at Medicine Rocks State Park, and fossils from the 

 southeastern part of the state are on display at the Carter County 

 Museum at Ekalaka. 



An interesting rock type scattered throughout the southeastern 

 part of the state is called clinker or porcelinite, formed when 

 the intense heat from a naturally burning coal seam melts the 

 surrounding rock. The resulting clinker is often resistant to 

 weathering and is often found on ridges. It can be seen in 

 scattered locations on many of the tributaries to Rosebud Creek 

 near Colstrip and because it is the most durable rock in the area, 

 it is sometimes used as gravel to surface dirt roads. 



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