120 THE FLORIST AND 
seemed to bring it out from its before insoluble silicates. Indeed, we can 
account for the natural fertility in the southern peninsula of Maryland and 
those districts of Virginia and G»eorgia where marl abounds, which we have 
visited, in no other way. In an acre of wheat or corn there is five times 
more potash than lime ; while the amount of soluble potash in natural pine- 
bearing soils is exceedingly small. A pine tree when burnt yields but little 
ashes, and they are not rich in potash. Pine leaves, however, yield pound 
for pound, twelve times more ashes than pine wood ; and it is mainly the 
annual fall of leaves on the surface of the ground, giving alkalies drawn 
from the deep subsoil, as well as organized carbon, oxygen and hydrogen, 
that enriches the land. By adding a little lime to this natural source of 
fruitfulness, the owner of pine lands will greatly enhance their value. They 
can be changed permanently from the production of coniferous plants to that 
of cereals — a difference as wide as that from a loaf of bread made of pine 
sawdust to one made of wheat flour. 
The difference in a soil that will yield pine wood abundantly, but wheat 
and maize very sparingly, is the pivot of plant rotation, to which the 
reader's attention is particularly invited. The volatile alkali called 
ammonia, which abounds in Peruvian Guano, works this change in piney 
woods land for one or two crops, in a remarkable degree. Wood ashes also 
produce signal effects on such soils, being far more lasting than guano. 
Alkalies in some form appear to be necessary to change a pine-growing soil 
into one adapted to the cheap and permanent production of oaks, hickory 
and grain. 
Numerous facts, similar in purport to those above stated, are well known 
to every observing farmer ; but the reason suggested by Professor Johnston 
and others, why pine trees succeed oak forests, and the latter, or beech, or 
other hard deciduous trees succeed pines, do not appear to us entirely satis- 
factory. On the rich lands of the Western States, and in Western New 
York, where beech and maple, or oakbearing soils are left to grow up a 
second time in forests, they do not, like the comparatively poor land of 
New Jersey, Delaware, Maryland, Virginia, North and South Carolina, and 
Georgia, produce a crop of old-field pines, but a second growth of the trees 
of the primitive forest. Coniferous plants never supersede those of a higher 
order and more complex development where the latter can flourish. 
If pines di'ive out oaks and poplars, it is because the latter find an 
uncongenial soil, made so not by nature, but by the labor of man. Nature 
never rotates her vegetable productions from a higher to a lower order of 
organism, if her developments are not molested. The deeply descending 
