THE SILVA OF COLORADO 57 
Altitude: 5,000 to 9,000 ft. Collections: near Boulder; South Boulder Canyon; 
Flagstaff Mountain; “Boulder” (Rydberg). 
Dasiphora fruticosa (Linn.) Rydb. SHRUBBY CINQUEFOIL 
Handsome flowering shrub in moist meadows and along streams. 
Altitude: 8,000 to 10,500 ft. Collections: Allenspark; Mt. Alto Park; Eldora; 
Redrock Lake, west of Ward. 
Holodiscus dumosus (Nutt.) Heller. MEADOWSWEET 
A handsome white-flowered shrub resembling some of the cultivated species of 
Spiraea. Rare in Boulder County but well-known farther south. 
Altitude: 7,000 to 8,500 ft. Collections: a single specimen collected by J. I. McFar- 
land in 1881 is labeled “Boulder County.”” Not seen in Boulder County by the writer. 
Kunzia tridenta (Pursh) Spreng. 
A low, much-branched shrub of rocky hillsides. 
Altitude: 6,500 to 8,500 ft. Collections: Head of Gregory Canyon; north of Nader- 
land. 
Opulaster glabratus Rydb. NINE BARK 
A dwarf shrub on ridges and in gulches. 
Altitude: 5,000 to 10,000 ft. Collections: Bluebell Canyon; South Boulder Canyon; 
Sugarloaf Mountain; ‘Boulder’ (Rydberg). 
Opulaster intermedius Rydb. NINE BARK 
On moist cliffs and in gulches. 
Altitude: 6,000 to 8,600 ft. Collections: Sugarloaf Mountain; Eldora; “lower 
Boulder Canyon” (Rydberg). 
Opulaster monogynus (Torr.) Kuntze. NINE BARK 
A medium-sized shrub on moist hillsides and in gulches. This is the best of our 
native species of Opulaster for planting as an ornamental shrub. 
Altitude: 6,000 to 9,000 ft. Collections: Bluebell Canyon; Gregory Canyon; 
North Boulder Canyon; Spencer Mountain at Eldora. 
Opulaster ramaleyi A. Nels. NINE BARK 
A shrub sometimes two meters high. In canyons and gulches. 
Altitude: 5,000 to g,ooo ft. Collections: near Boulder; Boulder Canyon near 
mouth; Gregory Canyon; Boulder Canyon near mouth of Fourmile; Boulder Falls; 
Magnolia; Eldora. 
Rosa aciculata Ckll. Wuitp RosE 
Altitude: 6,000 to 9,000 ft. Collection: “mountains between Sunshine and Ward.” 
(Rydberg). 
Rosa engelmanni S. Wats. WILD ROSE 
Altitude: probably from 6,000 to 10,000 ft. Collections; Eldora; foot of Long’s 
Peak; Boulder Canyon, 7,340 ft. 
Rosa fendleri Crepin. Wu£ILD ROSE 
Altitude: 5,000 to 9,000 ft. Collections: Marshall; above Magnolia; “Boulder; 
between Sunset and Ward” (Rydberg). 
