Calochortus bruneaunis has been found in Montana only two or 

 three times and only once recently. Its sagebrush-grassland 

 habitat is common throughout the area, and yet we were unable to 

 locate any populations. The response of this species to 

 livestock grazing is not known. The rarity of this plant 

 indicates that it should be considered for sensitive status if 

 populations are found on lands administered by BLM. 



Carex parryana ssp. idahoa. Primula incana, Thelypodium 

 sagittatum and Thlaspi parvlflorum are all associated with 

 calcareous wet meadows, and with the exception of T. parvlflorum, 

 are restricted to these habitats. Carex parryana idahoa is 

 palatable and probably decreases with cattle grazing, while the 

 responses of P. incana, T. sagittatum and T. parvlflorum to 

 grazing are not known. Primula incana and Thlaspi parvlflorum 

 may require moderate levels of disturbance to persist. However, 

 it is likely that all species will decline with heavy disturbance 

 early in the year when the ground is wet (Fig. 3) . Furthermore, 

 moderate to heavy grazing often leads to an increase of exotics 

 such as Kentucky bluegrass (Poa pratensis) and Canada thistle 

 {Cirsium arvense) that displace natives. Wet meadow habitats are 

 uncommon in the study area and, with few exceptions, throughout 

 the rangelands of southern Beaverhead County. Most wet meadows 

 are on private land and receive heavy livestock use or are used 

 for hay production. The chances of long-term persistence of C. 

 parryana idahoa, P. incana and T. sagittatum on these private 

 lands are not great. Carex parryana idahoa is proposed for 

 listing as sensitive by Montana BLM. Primula incana and T. 

 sagittatum should also be placed on a list of sensitive species, 

 and calcareous wet meadows on public land should be managed in a 

 manner that is compatible with the long-term persistence of these 

 rare species. The springs and meadows north of Box Spring are 

 relatively extensive and should be given special consideration. 



34 



