THE PLANT WORLD. 165 



JACK OAKS IN OKLAHOMA. 



By Charles Newton Gould. 



THE rivers in OkLahoma flow southeast. 15eginning on the north 

 they are: Arkansas, Salt Fork, Cimarron, North Canada, South 

 Canada, VV^aihita and Red River. Throughout the Territory 

 these streams average 25 miles a part. The country through which 

 they flow slopes gently to the southeast. Throughout there entire 

 course in the Territory these rivers flow across the Red-beds. This 

 formation which comprises nearly all the rocks of the Territory con- 

 sists principally of red sandstones and shales. The rivers, however, 

 take their rise in the Tertiary formations of the Plains in the western 

 part of the Territory or northern Texas and have brought great quan- 

 tities of sand from their upper courses. With the exception of the 

 Washita, which has a deep and narrow bed, all the streams have low 

 sandy banks and channels from one hundred yards to half a mile wide. 

 If there be any water in these channels it is usually a small stream 

 scarcely more than ankle deep meandering over the sandy bed. 



With reference to general topography and character of soil the 

 whole country lies in zones or l)ands parallel to the course of the 

 streams. Generally the channel hugs the sand bank. This causes 

 the steeper slope to be on the south. In this slope numerous canyons 

 have been carved out from the red clay and sandstone by the action of 

 the water. North of the streams the slopes are ordinarily gentle, and 

 are in many cases covered with sand hills. On the divide between the 

 streams the country is usually level, and extremely fertile. So in 

 travelinij southwest at the right ansrles to the course of the streams 

 one would cross first a high level prairie, then a sand hill country, 

 then the river bottom with its bed of sand, then a rather steep slope 

 more or less cut up with canyons, and finally the high prairie again. 



It is in the sand hill region of the north slopes of the difl'erent 

 streams that the jack oak (Qxercus Mfd'fjlanduYi) h found in great 

 abundance. Whatever be the origin of these sand hills, — whether 

 they are wind-blown deposits from the rivers to the south, or remnants 

 of the Tertiary formation which once covered the entire country — the 

 fact remains that here, and here alone the jack oak flourishes in central 

 Oklahoma. 



In the southeastern part of the Territory this tree is much more 

 abundant. The sand hills of Pottawatamie, Lincoln and the eastern 



