MONTANA BOTANY NOTES 25 



The typical form has the bark flaking up in thin and papery white sheets 

 even in young trees. It is very common throughout the region to St. Mary's 

 Lake on the Atlantic slope east of Blackfoot Glacier. 



Betula alba var. pendula (Roth Fl. Ger. t 405 (1788) as species). M'r. 

 Butler again dissects this and makes new names out of forms such as B. 

 subcordata Rydberg, B. Montanensis Butler, and curiously refers B. occi- 

 dentalis Hooker to it, when the typical form of it is described as low and 

 shrubby. (See DC Prod. 16 2). His B. Montanensis is founded on a single 

 old and partly dead tree. This shades by imperceptible degrees into the type. 

 It is characterized by the bark peeling off more tardily and in rather thick 

 and cardboard-like layers. This also is common in our region. This is 

 called B. occidentalis by Blankenship in his Supp. Fl. Mont. 48. 



AInus incana (L.) Willd. This is very common from Alta to the Sperry 

 Glacier region along creeks and lake shores at low elevations. The var. vir- 

 escens Watson has been reported from Flathead Lake but diligent search 

 fails to reveal it though it is common east and south but out of our range. 



AInus crispa (Dryand) Pursh. This is the A. viridis and A. Alnabetula 

 of most writers. It is rather common on mountain sides in subalpine places 

 going up to alpine meadows, from Alta to the Sperry Glacier region. 



Oaks have been reported from our region but every case proves to be 

 wrong so far. 



Urtica gracilis Ait. Frequent in wet woods and along creeks under Wil- 

 lows from Alta to Gunsight Lake. 



Urtica Breweri W^at. has been reported from our region but all specimens 

 prove to be the above. 



Arceuthobium Douglasii Eng. This grows on the red fir making the 

 twigs spindle out and droop like the weeping willow, and in large tufts, it 

 aborts whole limbs. The tufts are 4-6 feet wide and 2-3 feet thick. The 

 parasite runs along under the bark and breaks out at the joints. It seems 

 to bloom early in the spring, as next season's buds were forming in July. 

 It is very common throughout our region but good fruit is seldom seen. 



Arceuthobium Douglasii var. Tsugensis (Rosendahl Minn. Bot. Stud. 3 2 

 273 (1903) as Razoumofskya). This has not yet been found in our region 

 but is to be expected on the hemlock. 



Arceuthobium Douglasii var. Laricis (Piper Fl. Wash, 223 (1906) as 

 Razoumofskya). This is also very common but is seldom seen in fruit. It 

 acts in the same way as on the red fir as to aborting branches but the 

 tufts are rigid and very knotty, and twigs are thickened, short and rigid 

 and congested in small tufts 2-3 feet wide and a foot thick. The stems are 

 thicker and longer on the parasite than in the type. McDonald Lake in the 

 Mission Mts., Bigfork and Yellow Bay, both in flower and fruit, Aug. 12, 1908. 



Arceuthobium Americanum Eng. Alta, on Pinus Murrayana. 



Comandra umbellata var. pallida (DC.) Jones. Common on dry prairies 

 and on dry mountain .'Slopes from the Lower Missoula river to Browming. 



Polygonum minimum Wat. iMcDonald peak and Mission Creek, also 

 Sperry Glacier to Gunsight Pass and Lake, subalpine. 



Polygonum Douglasii Greene. Common in dry and gravelly places from 

 Alta north and east. 



Polygonum polygaloides Meisner. Upper Marias Pass. 



Polygonum bistortoides Pursh. Frequent on all the high peaks, also at 

 Evaro and Mission Creek. 



Polygonum viviparum L. Lambert Valley, Sperry Glacier to Gunsight 

 Pass. 



Polygonum Pennsylvanicum L. Bigfork, Echo Lake. 



Polygonum Persicarioides HBK. Darby. 



Polygonum Persicaria L. St. Ignatius Mission. 



Polygonum punctatum Ell. Poison Swamp, St. Ignatius Mission. 



Polygonum Hydropiper L. Poison Swamp. 



Polygonum alpinum All. Como Peak. 



