13 

 E. Population demography and biology 



1. Demographic details: Numerical estimates of population size 

 range from 50 to thousands of plants, and the taxon was 

 considered "common" at two recently surveyed sites. When 

 the population at Bannack was originally discovered only 9 

 plants were found (Heidel 1993), but over 1,000 plants, 

 covering about 5 acres were estimated in 1994. This 

 population consists of fewer plants, and is confined to a 

 smaller area than the sympatric population of Lomatium 

 attenuatum and the nearby population of Sphaeromeria 

 arqentea . 



2. Reproductive biology: Lesquerella sp. novum I is a small, 

 short-lived perennial which reproduces entirely by seed. 

 Species of Lesquerella are generally cross-pollinated and 

 self-incompatible (Rollins and Shaw 1973). The plants 

 generally flower from late May to late June, with flower and 

 fruit stages often overlapping on the same plant and within 

 an inflorescence due to an indeterminate growth habit 

 (Heidel 1993). The population structure, habitat, and plant 

 habit of Lesquerella sp. novum appear to be very similar to 

 those of Lesquerella carinata var. lanquida , whose 

 population biology has been studied in depth (Greenlee 

 1994). These bladderpods seem to have populations which are 

 subject to drastic fluctuations in numbers which follow 

 climatic cycles, especially at severe (i.e. hot, dry) sites. 



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