THE SOILS OF FLORIDA. 
55 
of glaciers is characteristic. The ice sheet moving slowly holds the 
smaller rocks firmly and pushes them slowly over the stationary 
underlying rocks, grinding the rocks to a fine powder, which subse¬ 
quently re-accumulate as soil materials. The glacial soil is often 
rich, consisting as it does of rocks thus artificially ground, having 
been less affected by the dissolving and assorting power of water 
than other soils. 
PLANTS AND ANIMALS. 
The action of plants and animals in the disintegration of rocks 
and the formation of soils is important. The roots of plants pene¬ 
trate the rock crevices and as they grow pry apart the rock, thus 
enlarging the opening. Seeds of plants likewise fall into crevices 
and by their growth open wider the natural breaks in the rock. 
Moreover, the roots of plants secrete acids which act as a solvent on 
the rock. Some marine animals bore into the rocks, while on land 
many different animals bore into the soil, thus bringing the deep 
and less thoroughly disintegrated soil to the surface, and also per¬ 
mitting the rainfall and the air to have free access to the deeper 
soils. In Florida the so-called salamander, a small rodent, Geomys 
turn floricianus, bores extensively in the sandy soils. This animal 
however, is adverse to moist conditions, and inhabits only the sandy 
well-drained lands. In the moist low lands the Cray fish are the 
most conspicuous borers, bringing up large amounts of the sub-soil 
to the surface. This type of land is familiarly known as “crayfish” 
land. Among the other borers which affect soils may be mentioned 
the earthworms, ants and “gophers”, the last mentioned being a 
term applied in Florida to a species of land tortoise. 
ACCUMULATION OP DISINTEGRATED MATERIAL. 
The material resulting from the disintegration of rocks may 
remain in place as formed, or may be transported a greater or lesser 
distance. The agencies of transportation are numerous, The work 
of boring animals and of plants referred to above assist in the trans¬ 
portation of soils by loosening the material and bringing it to the 
surface. The wind is an agent in transportation, the finer particles 
of the soil being freely moved by the wind. The extensive line of 
sand dunes bordering the Florida coast are chiefly wind blown. The 
valleys and depressions are continuously receiving small additions 
of fine sand and dust particles blown in by the wind. The chief 
