31 



II. 



Notes on the Canon Flora of Siodx County, With List of Plants Col- 

 lected IN July and August, 189'2, by A. P. Woods. 



Sioux county is the northwest corner county of Nebraska. It 

 is drained to the northeast by Hat creek with its tributaries, the 

 Long Branch, Sand, Dry, Sowbelly, Warbonnet, Squaw, and An- 

 telope. These tributaries radiate from the principal stream in such 

 a way as to present the appearance of a fan. The line of the di- 

 vide between Hat creek valley and the White river country be- 

 gins at the northeast corner of the county and passes southwest, 

 almost directly towards the southwest corner of the county, to 

 near Andrews, on the Fremont, Elkhorn and Missouri Valley 

 railroad. From this point the general trend of the canon coun- 

 try is slightly northwest. Hat creek basin is several hundred 

 feet below the level of the table land to the south. 



The creeks have their sources in canons, which generally have 

 the same name as the creek. In most cases the canons proper 

 are cut and divided by many smaller side canons, sometimes 

 very narrow and deep, having a rivulet at the bottom, fed by a 

 spring at the head of the canon and by smaller springs at the 

 side. 



In nearly all cases the sides of the canons are covered with a 

 rather dense growth of pine — Pinus ponderosa var. scopulorum. 

 Juniperus virginiana occurs here also. Higher up, along the 

 buttes, a prostrate form of Juniperus communis is very common. 

 Lower down, the monotony of the pine forest is broken by the 

 general intermingling of Ulmus americana (comparatively large 

 trees, sometimes two or three feet in diameter), Acer negundo, 

 Populus monilifera, P. iremuloides, Ostrya virginiana, J^raxi- 

 nus viridis, Betula occidentalis, and Acer glabrum. The latter 

 is usually a small tree, but in Squaw canon I found an individ- 

 ual about four inches in diameter and from fifteen to eighteen 

 feet high. Pdvthenocissus quinquefolia and Hamulus lupultis 

 often bv twining in and out among the underbrush and trees 

 make dense jungles, difficult to penetrate. 



