FREE INSTITUTE OF SCIENCE 
VEGETATION OF SOUTH FLORIDA 
95 
LIST OF PINELAND SEDGES 
. Rhynchospora Cymosa Ell. 
. Rhynchospora divergens Curtis. 
. Rhynchospora Grayi Kunth. 
. Rhynchospora stipitata Chapm. 
. Scleria ciliata Michx. 
. Scleria verticillata Muhl. 
. Stenophyllus Carteri Britton. 
. Cyperus compressus L. 
. Cyperus haspan L. 
. Cyperus Martindalei Britton. 
. Cyperus Pollardi Britton. 
- Dichromena floridensis Britton. 
. Dichromena latifolia Baldw. 
. Fuirena scirpoidea Michx. 
r | 
ORO OQ 
These lists show the character of the ground flora of the Slash-Pine Forma- 
tion in southern peninsular Florida. It should be emphasized that these 
species rarely form pure associations, but they are scattered over the forest 
floor, a species here and another there. The surface soil is fairly well covered 
with plants, so that at a distance it seems completely covered with annual 
and perennial herbs, but a close inspection shows that in some cases the plants 
are widely spaced and separated by the fragments of limestone, or by stretches 
of bare sand and apparently in open formation. When one considers, how- 
ever, the possible places where plants can grow between the rocks, the open 
character of the growth is due to the restrictions of soil room. In other places, 
the ground flora is much denser and the formation may be considered to be 
closed. 
Climatic Factors.—The rocky soil of these pine forests is well suited to the 
growth of the citrous fruits, notably the grape-fruit, Citrus decumana Murr. 
and the orange, Citrus aurantium L. In some cases, it is necessary to blast a 
hole with dynamite before setting out these fruit trees. Under ordinary con- 
ditions of weather, the soil is porous and the water which falls as rain is rapidly 
lost by percolation through the sand and by the limestone holes to the under- 
ground channels. During the dry season, the plants are under essentially 
xerophytic conditions and this fact was emphasized in the field notes of the 
writer during his first and second visits to the peninsula. The slash-pine is 
Structurally a xerophyte and many of the other plants are possessed of 
xerophytic structures. Notwithstanding the fact that the plants are adapted 
to meet the conditions of a porous soil, and a high evaporation rate, yet there 
are seasons when torrential rains fall, when even the soil of the driest pine for- 
est may be submerged with water for a shorter, or a longer, period. T his fact 
was forced home on the third visit to Florida in June, 1912, when for seven or 
eight days without much cessation it rained almost continuously until 17 
inches of rain had fallen. The pine woods on the west coast outside of the 
4 
