FOREST RECONNAISSAXCE OF THE DELAWARE PENINSULA 555 



The percentages for the peninsula as a whole, being made up from the 

 returns for six regions, have only about one-sixth the liability to error 

 of those in any one region, and can be given with more confidence ; and 

 they are given in figures to the nearest tenth in the last column. (This 

 suggests a method of making a rapid inventory of the forests of a single 

 state, in which most persons will wish to know only the state percent- 

 ages and the region where each species is most abundant.) 



At the head of the table, to facilitate comparison, are put the figures 

 already given in the regional descriptions for the percentage of forest 

 remaining and for evergreens, and also the average amount spent for 

 fertilizers in 1909 per acre of improved land in 1910, this last being a 

 rough measure of the fertility of the soil. 



The figures for forest area, evergreens and fertilizers all indicate a 

 progressive and fairly regular decrease in soil fertility in going from the 

 fall-line toward the coast. ^* The relative abundance of many of the 

 trees shows a corresponding gradation. For example, Pimis Tarda, the 

 most abundant of all, increases decidedly in abundance toward the coast, 

 though climate is doubtless a factor here, too, for the northern part of 

 the peninsula is almost too cold for it. Hicoria alba, Jitglans, Betida, 

 Fagiis, Castanca, Oucrcus Michaiixii, Q. paliistf'is, Moms, Liriododcn- 

 dron, Liqiddambar, and Nyssa, all decrease coastward, presumably on 

 account of soil conditions, for most of them are also perfectly at home 

 in the richer parts of Florida. Still another group of species, including 

 Finns rigida, P. cchinata, Taxodiiim, Chamcucyparis, and Qucrcus nigra, 

 with Magnolia glauca among the small trees, are most abundant near 

 the center of the peninsula, while several others seem from the available 

 evidence to have an anomalous distribution. Some of the last category, 

 however, will doubtless be found on more thorough exploration to be- 

 long in one of the groups just indicated. 



" It should not be inferred from this, however, that a similar gradation is char- 

 acteristic of the whole coastal plain. Farther south the coastal plain is more di- 

 versified, and cannot be divided so regularly into parallel belts as on this peninsula. 



