THE SOUTHEEJST CYPEESS. 9 



DURABILITY. 



The great durability of the heartwood, probably more than any 

 other property, gives cypress the place of distinction which it holds 

 among the more valuable woods on the market. In contact with the 

 soil or exposed freely to water or atmospheric conditions the heart- 

 wood ordinarily resists for many years the agencies of decay, while 

 the sapwood under the same conditions is comparatively short-lived. 

 Instances of cypress shingles 1 lasting 50 to 100 years, fences in good 

 condition after 40 years, old plantation buildings in the warm, humid 

 Southern States in excellent preservation after 100 to 200 years, 2 and 

 others of a like character are frequently reported. 



As the result of tests under way the Forest Service will be able 

 later to furnish information in regard to whatever relationship may 

 exist between color, oil content, and durability. The amount of oil 

 or resin content in the wood varies considerably and is judged by the 

 soapy feeling, which is somewhat characteristic and aids hi identifying 

 cypress. The name "cypressene" has been applied by some to this 

 resin. 



Cypress, like most other woods, is not entirely uniform hi respect 

 to durability. In fence lines some posts have to be replaced sooner 

 than others; in boats some planks decay while others last almost 

 indefinitely. In old cuttings the flat tops of large stumps are ob- 

 served to vary in soundness although of exactly the same age. The 

 seasoned heartwood when exposed to the weather appears to wear 

 out by the mechanical action of water and atmosphere before it gives 

 way through decay. Pecky cypress, although mechanically weaker 

 than sound cypress in proportion to its bulk or mass, is very durable. 

 The fungus producing the pecky wood is not known to cause any 

 further injury after the tree is cut. 



MOISTURE AND SEASONING. 



The water content of living cypress is variable, and in the lower 

 part of the trunk quite large in amount. Green cypress logs are 

 nearly double the weight of air-seasoned wood. In logging opera- 

 tions trees are girdled in advance of felling in order to increase their 

 buoyancy. (Sec p. 12.) The prevailing belief is that green cypress 

 contains more water and dries at a slower rate than other kinds of 

 "softwoods." Experience 1ms shown that cypress is a rather diffi- 

 cult wood to season, both in the air and. in the dry kiln, with a ten- 

 dency to caseharden in the Latter method. Preliminary experiments 

 indicate that, in kiln drying, cypress requires a length of time more 

 nearly like the hardwoods than the conifers. There is little doubt 

 thai cypre wood can be successfully dried when properly handled. 



> Tim iplll ; li " "tc. 



iMulU-n. • .<-. eoo|,i.| • liivrr, :-'..<'., I. uill, in I'/ll. 



