10 
North Carolina Experiment Station 
Habitat. Level land with dark humus-filled, fine sandy soil under¬ 
lain with a stiff non-draining subsoil. Free surface water, a few 
inches deep, is commonly present though in periods of extended drought, 
this may disappear. The soil under the latter condition may become 
baked into a hard caked layer, through the fact that the non¬ 
draining subsoil prevents the ascent of the water lying beneath it. It is 
thus seen that from a soil water standpoint, this is a habitat that under¬ 
goes marked changes. 
Physiogonomy. All of the plants of this formation show definite 
xerophytic tendencies. They are almost uniformly herbaceous and of 
the types with buried stems. This latter character is correlated with 
fire survival. The commonest type, perhaps, of underground stem, is 
that of a primitive bulb in which the bases of the radicle leaves enter 
the ground to a depth of two to three inches, there joining the buried 
stem. 
Associations. The very distinctive plants of this formation are so 
uniformly distributed in the uniform habitat that subcommunities of 
the rank of association are not clearly differentiated. A number of 
societies, however, may he mentioned: 
Dichromena latifolia Aletris farinosa 
Polygala lutea Dionwa muscipula 
Calopogon graminifolia 
Fig. 5. Dionsea muscipula, a minor element in the Savannah formation 
