INTRODUCTION 31 



men is lost on account of weather conditions or some other dif- 

 ficulty. In a work designed especially for identification purposes 

 it might be desirable to gather twigs of every species, showing 

 leaves and flowers or fruit, and photograph them against a suitable 

 background. That has been done in a few cases, but to do it for 

 300 species would be a pretty expensive undertaking. 



The 6(i half-tones (including 11 previously used in Mono- 

 graph 8) illustrate .33 species of trees and 10 of shrubs, in 22 

 counties. Those taken by other persons than the WTiter are prop- 

 erly credited. All are dated, for plants vary considerably in ap- 

 pearance in different seasons and different years. In a few cases 

 two views of the same tree taken at intervals of several years are 

 presented. 



Next the principal economic properties are given, as deter- 

 mined by observations in the field in this and other states, and 

 examination of nursery catalogues, dispensatories, government bul- 

 letins, tree manuals, etc. This indeed might be classed as text-book 

 matter, and therefore out of place; but the justification for includ- 

 ing it here is that some of it is new and original, and even the 

 compiled information is taken from many different sources, and 

 probably less than half of it could be found in any one existing 

 work. Even yet it is doubtless far from complete. 



Finally the usual habitat of the species is given, and its known 

 distribution within the state.* The distribution is given in detail 

 by regions, except in the case of some of the commonest and rarest 

 species, and sometimes with percentages of abundance. The 

 regions are numbered to correspond with the first map, as ex- 

 plained in the next chapter. 



For some of the s|)ecies there are distribution maps, made by 

 several different methods, but all on the same base as the regional 

 map. The ranges of species which are very abundant in some 

 regions and less so in others are indicated by dots varying in den- 

 sity. These dots do not necessarily indicate known localities, but 

 are merely a rough way of indicating relative abundance. W'here 

 a species is fairly common in suitable habitats in rather definite 

 areas, and apparently absent from others, oblique shading is used. 



*The type-locality and total range would also be of interest to some 

 readers, but those points are covered pretty well in Mohr's Plant Life of 

 Alabama, and very little could be added now to his information about them. 



