THE SOUTHERN CYPRESS. 7 



weight froni about 50 pounds per cubic foot to more than 62.35 

 pounds, the weight of an equal amount of water. 



In a series of tests the Forest Service x found that cypress wood 

 taken from all parts of the individual tree was strikingly uniform in 

 weight, structure of rings, and strength. 



As a rule the wood of cypress growing in ponds and other swamps 

 with acid soils averages much heavier than that of the typical form 

 growing along fresh, active streams. The wood from six representa- 

 tive trees growing in strongly acid pond soils in South Carolina 

 averaged 0.50 in specific gravity 2 as compared with 0.44 3 specific 

 gravity for four typical river cypresses from the fresh water of the 

 Savannah River bottom in the' same region. The heaviest wood 

 (specific gravity 0.55) in 39 representative trees taken from four 

 southern States was in a tree growing very slowly hi a pine-barren 

 pond in South Carolina. In the Dead Lakes of western Florida, 

 where an extensive cypress forest has been gradually inundated, 

 very slow growth in fresh, clear water produced soft, light-weight 

 wood. In swell butts, knees, and large roots, where growth is rapid, 

 the wood is very much below the average in weight. The lightest of 

 this wood is used to a limited extent as a substitute for cork, especially 

 for making fish-net floats and the like. One piece showed a specific 

 gravity under test of 0-19, or only 10 pounds per cubic foot, which is 

 considerably lighter than cork. During several months in the year 

 the water in the great overflow belt along the Mississippi becomes 

 increasingly stagnant and charged with humus compounds hi solu- 

 tion, resulting in moderately unfavorable conditions for growth. 

 This region produces much of the characteristic darker colored "red" 

 cypress of good average weight and strength. 



STRENGTH. 



In respect to strength cypress holds a position intermediate between 

 that of the white and the heavy yellow pines. The close relation 

 between weight and strength both in compression and cross-bending, 

 as shown by tests on cypress in a green state, is set out in Table 3. 



•Fen ' Ircalfli Vj, "Progress in Timber Physics: Bald Cypress," by Filibert Roth, p. 22. 



2 Banging from 0.42 to 0.68. 

 » Ranging from 0.39 to 0.48. 



