MESOPHILE ARBOREAL AND HERBACEOUS FLORA. 85 



where the sandstones overlie the calcareous rocks on the flanks of the 

 higher mountains. This highly ornamental tree, one of the rarest of 

 the Atlantic forests, is confined in the State to the mountains of 

 Madison County, where it attains a height of from 30 to 60 feet, with 

 a diameter of from 8 to 12 inches. The American smoke tree was 

 first discovered by Nuttall on the limestone cliff's bordering Grand 

 River, near the northeastern limit of Indian Territory. It was subse- 

 quently found in Alabama by Buckley, and has also been detected as 

 far west as the Medina Valley, in western Texas. Having disap- 

 peared from the locality where it was first discovered, and subsequent 

 to its discovery in Alabama not having been seen b}- any botanist, 

 the tree remained in obscurity for the next forty years, until it was 

 again brought to light by the writer in 1881. Later it was found hy 

 Mr. Bush^ in southwestern Missouri, and since then Professor Tre- 

 lease has found it in several localities in the Ozark Hills of the same 

 region. Being in the Tennessee Valley exposed to a temperature 

 falling not rarely nearly to zero, this tree will prove hardy in almost 

 every locality where the cultivation of its European relative is possi- 

 ble. In its native location it is readily reproduced by sprouts from the 

 stump, almost all of the vigorous coppice growths which it forms — for 

 instance, the one observed on the Gurley place (near Gurley) — being of 

 this origin. Red plum {Prunus americanci)^ red buckeye {Aesculus 

 pama)^ aromatic sumac {Rhus aromatica)^ redbud {Cercis canadensis)^ 

 with seedlings of the red cedar, form the bulk of the undergrowth of 

 the high forests, and coral-berry and shrubby St. John's wort {Ilyjyeri- 

 ciim jprolificuni) the bushy covering of the ground. 



Mesophile herbaceous plant associations. — The herbaceous flora on 

 these forest-clad heights is represented chiefly by mesophile plant 

 associations, which seek the shelter of the forest, or its borders and 

 more or less shady openings. Besides the species common through- 

 out the mountain region, a number of others are here found which are 

 widely distributed to the northern limit of the Carolinian area, but 

 occur rarely if at all in other regions of the State. Examples are: 



IXsporum lanuginosum. Thalidrum dtGicum. 



Uvularia puberula. Dentaria laciniata. 



Uvularia grancUflora. Pimpinella integerrima. 



Caulophyllmn thalidroides.' Washingtonia daytoni. 

 Anemone virginiana. 



On the densely shaded bluffs of the Tennessee River at Sheffield 

 landing a few mesophile species have been observed which deserve to 

 be mentioned. Of woody plants the Northern yellow wood ( Cladrastis 

 tinctoria)., a representative type of the lower souttiwestern AUeghenian 

 ranges, frequent from Kentucky southward, reaches here its extreme 



^ W. F. Bush, Trees and Shrubs of Missouri, St. Louis. 

 * Blue cohosh. 



