Demographic monitoring work at the three sites is confounded by 

 presence of plants with bract characteristics deviating from the 

 taxonomic circumscription of Moore and Frankton (1963) , including 

 both typical Cirsium lonqistvlum and C. hookerianum Nutt. bract 

 types as well as intermediates. One of the three monitoring 

 sites (Neihart) was interpreted as made up primarily of Cirsium 

 hookerianum , possibly with C. hookerianum x C. lonqistylum 

 hybrids present (Cronguist pers. commun. as cited in Roe 1992) . 

 Monitoring work of the following year included a companion 

 morphological investigation (Poole and Heidel 1993) . Closer 

 examination revealed a full range of bract characteristics which 

 are diagnostic in species identification keys. It was concluded 

 that, on morphological grounds alone, Cirsium lonqistylum 

 appeared to be a distinct species which hybridizes freely with C. 

 hookerianum to produce swarms of morphologically variable 

 individuals. It was recommended that this provisional 

 interpretation warranted genetic analysis, and that the 

 discreteness and persistence of a recognizable Cirsium 

 lonqistvlum genome be tested. 



Preliminary results of the genetic analysis will be submitted in 

 a separate document. The putative Cirsium lonqistvlum , 

 C. hookerianum and intermediates at C. lonqistylum sites were 

 compared with Cirsium hookerianum and C. scariosum material 

 outside the range of Cirsium lonqistylum using gel 

 electrophoresis and RAPD analysis. Genetic analysis work will be 

 extended and completed in 1994. 



The introduced weevil ( Rhinocyllus conicus) was identified as a 

 recurring seed predator at the onset of monitoring (Schassberger 

 1991, Schassberger and Achuff 1991) and was interpreted to 

 significantly affect seed output as indicated by the levels of 

 potential seed destruction. In this year's monitoring, weevil 

 infestation incidence was recorded inside the monitoring plots, 

 and seed destruction levels were also estimated. 



The particular study sites have natural and man-caused 

 disturbance regimes which differ from one another. While the 

 monitoring plots were set up for comparison between years and not 

 between plots or their disturbance regimes, the collection of 

 additional baseline data may aid in developing hypotheses to 

 understand the differences and interpret the divergent trends 

 between plots. Disparate disturbance factors were first recorded 

 as very pronounced between the three sites in 1991, with the 

 Neihart site having many plants (31%) that were grazed, affecting 

 at least seed output; and the Kings Hills site having intense 

 Columbian ground sguirrel burrowing activity, a factor in both 

 mortality and germination conditions. In this year's monitoring, 

 groundcover estimates were taken along the belt transect for the 

 first time as indication of burrowing activity. 



