SHKUB AND TREE ASSOCIATIONS. 45 



part and prevail in the openings and along the borders of the deciduous 

 forests in the northern half of the State. Twenty-four species of the 

 woody plants are of the liana form, stout climbers, which ascend the 

 highest trees, nearly half of their number belonging to the grape 

 family. Outside of the forest the shrubs rarely aggregate into an 

 independent "bush" formation of such extent as to make an impres- 

 sion upon the physiognomy of the vegetation and to form a proper 

 plant association. In the coast region, however, the following species 

 form to a limited extent thickets more or leso free from larger trees: 



Myrica cerifera (wax myrtle) . Rhododendron spp. (azalea) . 



Myrica inodora (wax myrtle) . Pieris nilida (andromeda) . 



Ilex cassine (dahoon holly) . Leucothoe axillaris (andromeda) . 



Ilex vomitoria (yaupon holly) . Kalmia latifolia (mountain laurel) . 



Osmanthus americanus (American olive) . Vaccinium and Gaylussacia spp. (huckle- 



Illicium floridanum (sweet illicium). berry, whortleberry). 



Symplocos tinctoria (horse sugar) . Vaccinium arboreum (farkle berry) . 



Bosquets of groundsels (Baccharis halimifolia), with marsh elder 

 (Ivafrutescens), dot here and there the salt marshes of the seashore. 

 The arborescent grasses of the bamboo tribe, the so-called cane, repre- 

 sented in eastern North America by Arundinaria macrosperma and 

 A. tecta, form by their spread over wide areas a most peculiar and 

 prominent feature in the vegetation of the State, known as canebrakes. 

 The big cane, attaining not rarely a height of from 20 to 30 feet, occu- 

 pies the more or less overflowed alluvial river banks. The so-called 

 reed or switch cane, of smaller size, forms the impenetrable under- 

 growth of the forests of the humid and fresh soil depressions, and is 

 most prevalent in the Cretaceous plain, designated as the canebrake 

 region. 



ARBOREAL PLANT ASSOCIATIONS. 



As in most parts of eastern North America, forests constitute in 

 Alabama the most extensive and predominating of plant formations. 

 Under the influence of the mild climate of relatively low latitudes with 

 an abundant rainfall evenly distributed throughout the year, condi- 

 tions most favorable to tree growth, Alabama presents the aspect of a 

 richly wooded country. From the mountain heights and valleys of 

 the north to the shores of the Gulf the State is clad in a robe of forests 

 scarcely surpassed in the diversity of their tree growth and timber 

 wealth by those of any other part of eastern North America. Origi- 

 nally the tree covering was almost uninterrupted. It can safely be 

 assumed that at present over 50 per cent of the area of the State 

 remains under cover of the original forest growth, although more or 

 less invaded by the ax in the more accessible localities. Of the 172 

 arboreal species recorded as growing without cultivation in the State, 

 15 are introductions from the warmer temperate and tropical regions, 

 mostly of the Old World, and 3 from the States of the Southwest. 



