Collar Gulch. Samples from the middle and lower sites were composed mostly of moss. 

 The sample from the middle site (near Collar Peak) was tan-colored and contained a large 

 amount of fine particulate organic matter. The moss in this sample was smothered with 

 filamentous green algae consisting of narrow un-branched filaments and small blocky cells with 

 parietal chloroplasts {Hormidium = Klebsormidium). 



Non-Diatom Algae (Table 3) 



Chicago Gulch. The tributary of Chicago Gulch supported 6 genera of non-diatom algae 

 in three divisions: Cyanophyta (cyanobacteria), Rhodophyta (red algae), and Chlorophyta (green 

 algae). This site was dominated by the filamentous green alga Mougeotia. a common and widely 

 distributed genus that contains many species. Two relatively pollution-sensitive genera — Nostoc 

 and Audouinella — were found here but not downstream. The presence of Stigeoclonium at this 

 site suggests moderate nutrient enrichment. 



The upper and lower sites on Chicago Gulch were each represented by only 4 genera of 

 non-diatom algae. The filamentous cyanobacterium Hydrocoleum was the most common alga at 

 the upper site, followed by another genus of blue-green algae, Calothrix. Also appearing here 

 was the filamentous green alga Hormidium {=Klebsormidium). Some species of Hormidium are 

 especially abundant in acid v/aters that are contaminated by high concentrations of heavy metals 

 (Wehr and Sheath 2003). The most abundant non-diatom alga at the lower site was Oscillatoria, 

 another cyanobacterium and a close relative of Hydrocoleum. The chrysophyte Vaucheria 

 ("water felt") was frequent at this site and its presence indicates steady flows of cool water. 



Collar Gulch. The three sites on Collar Gulch were each represented by three genera of 

 non-diatom algae. The upper site was dominated by the filamentous chrysophyte Tribonema, a 

 genus typically found in cold waters of low pH. Hormidium {^Klebsormidium) dominated the 

 samples collected at the middle and lower sites. As noted above, some species of Hormidium are 

 especially abundant in acid waters that are contaminated by high concentrations of heavy metals 

 (Wehr and Sheath 2003). 



