with coal-tar creosote; otherwise, one of the other treatments could be 

 satisfactory. 



(2) Piles and Poles . Wood piles and poles used in the coastal 

 environment are nearly all pressure treated with coal-tar creosote to 

 resist insect attack or, in water, marine borers and limnoria. Properly 

 treated piles and poles will also withstand rot and fungus attacks. Piles 

 are used for building foundations, support for piers, wharves, trestles, 

 jetties, groins, and bulkheads. Also, they are used in fender systems along 

 the wharves and to anchor floating moorings for small boats. 



It is unlikely that untreated piles or poles would be used in the 

 coastal environment except for temporary uses during construction for false 

 work or to carry electric power and telephone lines to the construction 

 site. 



(.3) Beams and Stringers . Lumber classified as beams and stringers 

 {having 5 inches (125 millimeters) as their least dimension} are seldom 

 used untreated in the coastal environment. The principal use would be in 

 protected space as framing for buildings or covered structures where the 

 covering or painting provides sufficient protection. 



Coal-tar creosote treated beams and stringers are used extensively in 

 the coastal environment. 



(4) Glued and Laminated Wood . 



(a) Plywood . Dry-use plywood is seldom used in the coastal 

 environment because of its extreme susceptibility to the generally high 

 humidity. Any use would have to be very temporary or very well protected 

 from the prevailing moisture. 



Wet-use plywood has many applications in the coastal environment. 

 Diaphragms in buildings, roofs, walls, and floors are regularly sheathed 

 with wet-use plywood. Plywood is sometimes used for gussets in wood frames 

 to join the members. Plywood is used extensively in making forms for 

 concrete work. Signboards are frequently made of plywood. Covers, such as 

 for pits and valve boxes, can be made of plywood where traffic is light or 

 in nontraffic areas. Wet-use plywood can be further treated with preserva- 

 tives to extend its useful life in extreme environments, such as immersion 

 in seawater. 



(b) Laminated Wood . Wood in this category is what is generally 

 referred to as "glue-lam," or more properly glued laminated wood. Because 



of its better quality control, strength, and capability of being sized to 

 suit the need, it can be the preferred material for many applications where 

 columns, posts, beams and girders are used. In the coastal environment, 

 wet -use glue is absolutely essential and glue- lam members must have pre- 

 servative treatment in any use where other wood forms would require it. 



(5) Miscellaneous Wood Forms . Although most people think of 

 finished lumber and timbers cut to rectangular sizes from large trees or of 

 piles peeled and trimmed when they think of wood, there are other useful 

 forms of wood that can be used in the coastal zone. Small branches, saplings, 



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