19211 PALMER, BOTANICAL RECONNAISSANCE OF SOUTHERN ILLINOIS 137 



sented by more numerous forms than in any other part of southern Illi- 



nois. 



Farther north along the Ohio River, from the Saline to the mouth 

 of the "Wabash and for some distance up the valley of the latter stream, 

 there is much low, level country; the broad alluvial flood plains are fre- 

 quently inundated; drainage in many sections is poor and swamps and 

 bayous abound. Such conditions obtain over a large part of Gallatin 

 County; and extending more or less continuously to the village of New 

 Haven is a line of sloughs and lakes, evidently marking an old channel 

 of the Wabash River, when that stream joined the Ohio some twelve or 

 fifteen miles south of the present junction point. The flora of this sec- 

 tion, like its topography, is generally quite similar to that of the Cairo 

 region, although several of the southern trees and shrubs have disappeared. 

 Cypress, however, persists nearly as far north as the mouth of the Wa- 

 bash, and is reported to have formerly grown in a swamp, long since 

 drained, near New Haven, at the mouth of the Little Wabash. On 

 the Indiana side it is still growing some distance farther north, and an 

 extensive Cypress swamp is said to have occurred in Knox County until 



destroyed by drainage. 



A short distance back from the Ohio River, near Shawneetown, a range 

 of low hills, underlaid by shales and sandstones of the Pennsylvaniau 

 series stand out above the surrounding alluvial plain. The contrast 

 in toi)ography is very striking, although at their highest points the hills 

 are little more than a hundred feet above the valley. The surface is 

 rather undulating tlian rugged, and in the northern portion, known as 

 the Sha^niectown Hills, scarcely any rock outcrops occur. In the Gold 

 Hills to the south, however, there are some low sandstone escarpments 



and the slopes are generally steeper. 



The hills, like the surrounding valley, originally supported a heavy 

 growth of deciduous trees. Much clearing has been done in the more 

 level portions, and most of the merchantable timber has been culled out. 

 A tract of some hundred acres of practically virgin forest in the Shawnee- 

 town Hills was cut for lumber during the year 1919. Many saw logs 

 from three to five feet in diameter, of Sweet Gum, White Oak and Tulip 

 Tree {Liriodendron ruUpifcra) were secured. To the last named species 

 the name of Yellow Poplar has been applied by the lumbermen, and 

 unfortunately widely adoi)tcd by the country people. 



In composition and general character of growth the flora of the Shaw- 



neetown and Gold Hills is quite similar to that of the Cretaceous area 



farther south, and the relation of the hills to the surrounding lowlands 

 here, although isolated and underlaid by a different geological formation, 

 closely approximates that of the Mounds and Cairo Formations; and the 

 flora of the respective stages may well be classed together. Amongst the 

 commonest forest trees on the uplands here are the Scaly-bark and Pig- 

 nut Hickories, White and Red Oaks, Black Gum, Sweet Gum, Tulip 

 Tree and Sugar Maple. Vines and undershrubs are not abundant in most 



