Table 1, Long term climatological data for Virginia City, 

 Lakeview, and Dillon, Montana. 



44 



Sites = 

 elevation 



Laurin Canyon (001) 

 8500 ft (2550 m) 



Elk Lake(002) 

 6800 ft (2040 m) 



French Creek (003) 

 7200 ft (2160 m) 



nearest weather 

 station 



station elevation 



mean annual 

 temperature 



mean maximun 

 teniperature in 

 July 



mean minimun 

 tetnperature in 

 January 



mean annual 

 precipi tat ion 



Virginia City 



5776 ft (1733 m) 

 'i2.4°F (5.7°C) 



81.3°F (21. rc) 



10.6°F (-11.9°C) 

 16.26 in (40.5 cm) 



Lakeview 



6710 ft (2010 m) 

 35.0°F (l.fC) 



76.5°F (24.9°C) 



0.5°F (-17.6°C) 

 20.52 in (51.3 cm) 



D i 1 1 on 



5228 ft (1565 m) 

 42.6°F (5.9°C) 



83.3°F (28.7"C) 



9.4°F (-12.7"C) 

 9.53 in (23.8 cm) 



Due to elevational differences between the 

 Virginia City and Dillon stations and their 

 associated populations, one could expect that the 

 populations would receive more precipitation than 

 is listed for the station, 



F. POPULATION DEMOGRAPHY AND BIOLOGY 



1. PHENOLOGY: This species flowers from June through 

 early July, with seeds maturing by late July and 

 early August. 



2. POPULATION SIZE AND CONDITION: Population size 

 estimates and condition are not available. 



3. REPRODUCTIVE BIOLOGY 



a. TYPE OF REPRODUCTION: This tap-rooted 

 perennial reproduces by way of seed. 

 Chromosome counts revealed 2N = 34-36 for C. 

 subniveum (Welsh et ai. 1987) . 



b. POLLINATION BIOLOGY: Species in the genus 

 Cirsium are pollinated most often by bees, 

 but other insects may serve as pollinators 

 (pers. obs. ) . 



c. SEED DISPERSAL AND BIOLOGY: The wings on the 

 seeds of species in the genus Cirsium aid in 



