3. SOIL RELATIONSHIPS: Soils are well-drained, coarse, sandy or gravelly 



loams. 



E. POPULATION BIOLOGY AND DEMOGRAPHY 



1. PHENOLOGY: The Lake County specimens of Harvey were collected in 

 fruit on June 29 and July 1 . In the study area, however, the species was 

 beginning to produce vernal inflorescences much earlier in the bum site, as 

 compared with the steep valley bottom; the latter began in the second week of 

 July during the relatively cool, wet 1995 growing season conditions. The 

 survey work conducted in 1995 was not optimally timed for this species. 

 Spikelets are expected to persist several weeks. Judging by the lateness of 

 vernal infloresences, it is not likely that autumnal infloresences are produced 

 earlier than late August. 



2. POPULATION SIZE AND CONDITION: Both populations are very small, 

 consisting of five clumps that represent discrete individuals. 



3. REPRODUCTIVE BIOLOGY 



a. TYPE OF REPRODUCTION: Strictly by seed, produced by vernal 

 (early season) infloresences and autumnal (late season) infloresences. 



b. POLLINATION BIOLOGY: Wind-pollinated. 



c. SEED DISPERSAL AND BIOLOGY: Unknown. 



F. POPULATION ECOLOGY 



1. COMPETITION: Members of the Dichanthelium genus typically occupy dry 

 habitats in low-competition settings. 



2. HERBIVORY: Unknown. 



3. FIRE: Scribner's panic grass survives fire, but the impact on population size 

 has not been discerned. In the burned Cabin Creek occurrence (003), plants 

 were earlier and had more stems as compared to the unbumed East Fork of 

 Otter Creek occurrence (002). This species does not exhibit the marked 

 increase in the wake of fire as does Wilcox' panic grass (Heidel and Dueholm 

 1995). 



G. LAND OWNERSHIP (MONTANA) 



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