21 



appeared to be very vigorous. During surveys 

 in 1V86 and 19B7» no evidence of any 

 vegetative reproduction was observed. 



b. POLLINATION BIOLOGY: During field surveys in 

 1986 and 1987, insects were occasionally 

 observed visiting the flowers of L. klausi i , 

 including one which appeared to be a member 

 of the genus Bombus (bumblebee). Rollins and 

 Shaw (1973) report that "(i)n the field, 

 insects, mostly bees and flies, were 

 repeatedly observed visiting the flowers" of 

 Lesquerel la . No other details of the 

 pollination biology are known at this time; 

 it is unknown whether there are any 

 specialized plant-pollinator relationships 

 involving L. klausi i . 



c. SEED DISPERSAL AND BIOLOGY: Each fruit of L. 

 klausi i is capable of producing four seeds; 

 the seeds are wingless, and about H mm. (0.08 

 in.) in diameter (Rollins, 198^). Thus, 

 there does not appear to be any mechanism 

 that might aid in long-distance dispersal. 

 It is likely that most seeds fall near the 

 parent plants. 



At the Hunters Gulch (001) site, numerous 

 seedlings were observed in 1985 and 1986. 

 This area was burned during the 198^ North 

 Hills fire, and it appears that this may have 

 invigorated the population; seed germination 

 may have been enhanced owing to a reduction 

 in competing vegetation, and/or the heat of 

 the fire. No detailed information is 

 available, however, on this or other aspects 

 of the seed biology of L. klausi i . 



G. POPULATION ECOLOGY 



1. BIOLOGICAL INTERACTIONS 



a. COMPETITION: As previously discussed 

 (I.E.I., p. 13), L. klausi i occurs most 

 frequently and abundantly on open, 

 sparsely vegetated slopes, often in 

 azonal soils. In addition, at nine of 

 the S7 known occurrences, the species 

 has partially colonized adjacent 

 disturbed areas, usually consisting of 

 steep, unstable roadbanks. These 

 observations suggest that L. klausi i 

 does not compete well in denser zonal 

 vegetation, i.e., bunchgrass communities 



