REPRODUCTIVE BIOLOGY 



a. TYPE OF REPRODUCTION: Lomatium bicolor var. 

 bicolor is a perennial species known to 

 reproduce by seed (Schlessman 1984). New 

 ramets may also be produced through extension 

 of the root system (pers. obs.). 



b. POLLINATION BIOLOGY: The umbels 

 (inflorescences) of L. bicolor var. bicolor 

 contain both perfect (male-female) flowers 

 and staminate (male) flowers. Schlessman 

 (1984) reports that species in this group are 

 known to reproduce by pollen transfer from 

 one flower to another on the same plant 

 (geitonogamous selfing) , and by outcrossing. 

 Pollination is then nearly assured, and some 

 seed production can occur even under adverse 

 conditions. 



Although there is often overlap in flowering 

 times of co-occurring species, hybridization 

 between species in the tuberous Lomatiums is 

 apparently not common. Controlled 

 interspecific crosses demonstrated strong 

 postmating isolating mechanisms (Schlessman 

 1984) . 



c. SEED DISPERSAL AND BIOLOGY: The seeds of 

 Lomatium species are often winged, and wind 

 dispersal may be possible (Schlessman 1984). 

 However, due to seed weight and size, it is 

 doubtful that seeds of L. bicolor var. 

 bicolor are blown vety far from the parent 

 plant. 



d. PHYLOGENY AND SPECIATION: Hybridization does 

 not appear to be pronounced in the tuberous 

 Lomatiums. Instead, geographical isolation 

 and divergence are probably the sole source 

 of speciation (Schlessman 1984) . Schlessman 

 (1984) contends that L. bicolor var. bicolor 

 is most closely allied with L. bicolor var. 

 leptocarpumr and secondarily with L. 

 quintuplex. However, Lincoln Constance 

 (pers. comm.) recently commented that L. 

 cfuintuplex may in fact be even more closely 

 allied with L. bicolor var. bicolor than var. 

 leptocarpum. Further study is necessary to 

 better understand the systematics of these 

 species. 



