at 3833 feet. For the period of 1951-1980, at 

 Townsend the mean annual precipitation was 11.11 

 inches, the mean January temperature was 19.7°F, 

 and the mean July temperature was 66.8°F; while at 

 Holter Dam the mean annual precipitation was 12.02 

 inches, the mean January temperature was 24.8°F, 

 and the mean July temperature was 69.9°F (U.S. 

 Department of Commerce 1982.) 



F. POPULATION DEMOGRAPHY, BIOLOGY AND SPECIATION 



1. PHENOLOGY: Polycfonum douglasii ssp. austinae 



flowers June through August (Hitchcock and 

 Cronquist 1964) . 



2. POPULATION SIZE AND CONDITION: Population sizes of 



annuals are expected to fluctuate, so any point- 

 in-time observations are to be taken as limited 

 indication of long-term conditions. Population 

 sizes outside the Helena National Forest are 

 reported as "locally common" or as a "large 

 colony". Populations sizes within the Helena 

 National Forest range from a low of 6 plants to 

 over 150 plants observed with possibly more than 

 1000 individuals total. Three of populations are 

 in excellent or good condition, with small areas 

 where it is locally common. One population (6 

 plants) is barely persisting. For more detailed 

 information on each site, see Appendix 5. 



3. REPRODUCTIVE BIOLOGY 



a. TYPE OF REPRODUCTION: Unknown. The small size 

 of the flowers suggests selfing. 



b. POLLINATION BIOLOGY: Unknown. 



c. SEED DISPERSAL AND BIOLOGY: Seeds probably 



fall close to the parent plant, and may be 

 disperse by rainfall or small animal vectors 

 (cached by insects or small mammals) . 



d. PHYLOGENY AND SPECIATION: As stated above. 



Polygonum douglasii ssp. austinae was 

 originally described and is sometimes 

 recognized as a full species. The 

 relationship between this taxon and P. 

 douglasii is very close. Perhaps at one time 

 the two were more distinct, and have been 

 brought into recent contact by human 

 disturbance, causing some mingling of their 

 genes. However it is just as likely that P. 



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