A8 BULLETIN 272, U. S. DEPARTMENT OF AGRICULTURE. 
posed chiefly of red maple, water oak, red oak, ash, honey locust, 
hackberry, and red gum, in association with mature cypress. In 
southeastern Mississippi a tract of 807 acres, mostly overflowed in 
winter and spring, contams the followmg hardwood associates of 
cypress, stated in the order of their relative importance: Ash, white 
and red elm, red maple, red and tupelo gums, various oaks, hack- 
berry, hickory, and cottonwood. In all of these higher glades groups 
of pure cypress occur in the depressions, and elsewhere older trees 
are scattered in mixture with the hardwoods. The gradual shifting 
of the main currents during floods produces changes in the location 
and height of the ridges in the glades, together with corresponding 
changes in the composition of the forest due to the different moisture 
requirements of the various species. | 
Over the southern Atlantic Coastal Piam, mature red gum, over- 
cup oak, water elm, water and Florida ash, and bitternut: hickory 
occupy the low ridges in the large riverswamps. Tupelo gum, water 
ash, and small amounts of cottonwood and water locust, along with 
cypress, stand in water during much of the year. Two other types 
in this region are found in the nonalluvial Dismal and Okefinokee 
Swamps, and the mixed white cedar and cypress swamps from Vir- 
ginia to Florida. The Okefinokee forest is made up essentially of 
heavy stands of pure cypress over the younger and middle-aged por- 
tions, and a dense hardwood forest with scattermg veteran cypress 
over the older-aged portions of the swamp (fig. 3). Among the hard- 
woods, black gum leads, and there is much white bay, red bay, red 
maple, and willow and water oak. The more valuable yellow poplar, 
red gum, and ash, if present, are in very small quantities. The 
white cedar peat swamps contain varying mixtures of cypress and 
white cedar, with pond and slash pine around the borders. 
Along the swamp borders cypress closely meets the many conifers 
and hardweods which compose the upland forests of the Southeast. 
The small cypress ponds of the flat, pme-barren type contain small 
amounts of water gum, a dwarf form of the black gum, while pond, 
spruce, and slash pines are encroaching actively from the outside 
as the ponds become drier through the destruction of the surrounding 
pine forest. 
YIELD. 
In pure stands and in the better cypress regions of the Southern 
States, particularly Louisiana and Florida, virgm cypress yields of 
8,000 to 14,000 board feet per acre are not uncommon over tracts 
several hundred miles in extent. The size of the trees and density, 
or number of trees per acre, is very irregular. In a few localities 
manufacturers are now cutting bodies of pure cypress contaming a 
total of up to 100,000,000 feet, which will average more than 20,000 
feet per acre. 
