STANDLEY — FLORA OF GLACIER PARK. 325 



The shrub is abundant in some places, but the stations are scattered and often 

 isolated. Above timber line the plants are sometimes spreading and only 30 to 60 

 cm. high. 



2. Betula fontinalis Sarg. Water birch. Along creek near St. Mary, and 

 probably elsewhere. Yukon to Utah, N. Mex., and Nebr.— Shrub or small tree with 

 very sticky twigs, the bark reddish brown; leaves broadly ovate, rounded or some- 

 what cordate at the base, nearly glabrous, coarsely toothed; cones 2 to 3 cm. long, 

 the fruit broadly winged. 



Most of the plants of St. Mary are only 1 to 1.5 meters high. 



3. Betula papyrifera Marsh. Canoe birch. Common on the west slope at low and 

 middle altitudes, along streams or lake shores, or often on rocky hillsides. Alaska 

 to Colo., N. J., and Lab. — Small or large tree with chalky white or, on young trees, 

 yellowish white bark; leaves broadly ovate, 4 to 10 cm. long, slender-stalked, obtuse 

 to subcordate at base, long or short-pointed, finely hair>' beneath or nearly glabrous; 

 cones 2 to 4 cm. long; fruit very broadly winged. 



Many of the trees about Lake McDonald are very large; they are often densely 

 covered with lichens. The bark of this species was formerly much used by the 

 Indians for making canoes. The wood is often employed in the manufacture o£ 

 paper. The canoe birch is a very handsome tree, its wliite bark contrasting strongly 

 with that of other trees with which it is associated. It is said to grow in a few places 

 on the east slope of the park, but this is doubtful. 



4. Betula occidentalis Hook. Western birch. Occasional on the east slope at 

 low altitudes. B. C. and Wash, to Mont. — Small or medium-sized tree with finely 

 hairy twigs; leaves thin, broadly ovate, 4 to 10 cm. long, somewhat hairy beneath, 

 long-pointed; cones 3 to 4 cm. long. 



2. ALNUS Hill. Alder. 



Shrubs or small trees with smooth, close, reddish brown bark; leaves slender- 

 stalked ; fruit with or without a wing. 



Fruit winged; twigs with resin dots, not hairy 1. A. sinuata. 



Fruit not winged ; twigs not resinous, finely hairy 2. A. tenuifolia. 



1. Alnus sinuata (Regel) Rydb. Green alder. Common at high and middle 

 altitudes, and occasionally, especially on the west slope, at low altitudes; along 

 streams or lake shores, in moist woods, or on open slopes. Alaska to Oreg., Wyo., 

 and Alta. — Shrub, 1 to 2 meters high, or sometimes a small tree; leaves broadly 

 ovate, 4 to 10 cm. long, bright green, acute or obtuse, thin, closely and sharply 

 toothed, scarcely at all lobed, nearly glabrous, but with tufts of hairs beneath in 

 the axils of the veins; cones 1 to 1.5 cm. long. 



This species often forms extensive, dense, nearly impenetrable thickets on slopes 

 at middle or high elevations. The stems are usually bent down, probably as a result 

 of the weight of overlying snow. It is only at low altitudes that this alder gets to be 

 a small tree. 



2. Alnus tenuifolia Nutt. Mountain alder. Common at low altitudes, along 

 streams or in wet places. Alaska to Calif., N. Mex., and Mont.— Shrub, 1 to 4 

 meters high; leaves oval or broadly ovate, 4 to 10 cm. long, thick, rather dull green, 

 shallowly lobed and with broad teeth, somewhat hairy beneath; cones 1 to 2 cm. long. 



This species nearly always grows at lower altitudes than A. sinuata, but sometimes 

 the two are found together. The Blackfoot Indians employed the tough bark for 

 making stirrups, which were covered with rawhide. They also used a hot decoction 

 of the bark as drink for the treatment of scrofula. Their name for the plant is "red 

 mouth bush," in allusion to the fact that when the bark is chewed the saliva is 

 colored red. 



