190 Nebraska State Horticultural Society. 



seeds and fruits, are efficient means for distributing the seeds of trees 

 and other plants. To these must be added the birds of nearly all species, 

 excepting those that subsist wholly upon animal food. Their power of 

 swift flight enables them to transport seeds long distances in every 

 direction, across barriers which are practically impassable for quadru- 

 peds. The number of different species which take part in seed dissemi- 

 nation is not less than two hundred in the portion of the central plains 

 included within the boundaries of Nebraska, and of these probaby one- 

 third carry the seeds of trees. 



Nebraska occupies a central position in the United States, and is 

 somewhat south of the center of the North American continent. It lies 

 between latitude 40 to 43 degrees north of the equator, and longitude 

 95 degrees 30 minutes to 104 degrees west of Greenwich. It lies almost 

 wholly in the Great Plains region, or the "Prairie Province" as de- 

 nominated by Pound and Clements in the "Phytogeography of Ne- 

 braska." In the valley of the Missouri river along its eastern border 

 its elevation above sea-level is 8 SO feet at the southeast, and about 

 1,100 feet at the northeast, while westward and northwestward the 

 elevation is much greater, reaching 4,900 feet in the northwest, and 

 fully 5,300 feet toward its southwest boundary, near the Wyoming 

 line. 



The river system is a very simple one. Along the eastern border 

 is the turbid Missouri river, which receives the Nemaha and Weeping 

 Water (both short streams) south of the mouth of the Platte river. 

 The Platte river flows from the Rocky mountains as two streams, which 

 unite in western Nebraska, and is, like the Missouri river, a rapid and 

 turbid stream. It receives one tributary, Lodgepole river, in the west- 

 ern part of the state, the much-branched Loup river (which drains the 

 Sand Hills) in the center, and the Elkhorn river toward the north- 

 easterly part. On the north is the Niobrara river which comes from the 

 Wyoming foothills, and in the extreme northwest are branches of the 

 White river, rising in the mountainous country of Pine Ridge. On the 

 south the Republican river comes from the elevated plateau of eastern 

 Colorado, traverses the southern counties, and then passes into Kansas, 

 Avhere it joins the Kansas river, and finally reaches the Missouri river. 

 In the southeast, the Blue river drains a triangular area closely ad- 

 jacent to the Platte river, and flowing south empties into the Kansas 

 river. 



The surface features of the state are considerably varied, including 

 the wet and marshy "bottoms" of the Missouri river valley, the steep 

 "bluffs" which limit them on the westerly side, the hilly and broken 

 country still further inland, the rolling surface of the prairies of the 



