906 



AMERICAN FORESTRY 



is determined by the size of the annual rings and tho 

 proportion of dense or "summer" wood which they con- 

 tain. Lumbermen and timber engineers are discussing 

 the adoption of revised grading rules which shall take 

 these facts into account and will result in furnishing to 

 consumers longleaf timbers of a uniform strength as 

 well as freedom from defects. Longleaf pine is also one 

 of the most durable of imiwrtant structural woods, both 

 in air and in contact with water or in the soil. It is 

 possible to obtain clear sticks in dimensions up to 14X1-1 

 inches by 70 feet, and there are records of some even 

 larger. Derrick booms, masts, flag poles, trestle beams, 

 and timbers for buildings of the slowburning or "mill 

 frame" construction type demand these timbers. A 

 rather unexpected use came to the attention of the writer 

 recently when he saw an order for longleaf timbers to 

 build the framework for targets for big gun practice in 

 the Navy. 



We are hearing a great deal these days about the 

 danger of using wood for construction purposes, since 

 for.sooth it will burn. The fact has been advertised as if 

 it were a recent discovery, at the same time those most 

 interested in circulating this interesting bit of informa- 

 tion have failed to inform us that steel will melt and 

 cement will crumble. If a longleaf timber and a steel 

 beam constructed to support the same load are placed 

 side by side and subjected to a fire of the same intensity 

 the steel beam will become red hot and bend under its 

 load before the longleaf beam will have burned through 



and broken. A fire hot enough entirely to consume long- 

 leaf timbers of any size will reduce an unprotected steel 

 beam to a mass of twisted iron. Indeed it is very diffi- 

 cult to burn a longleaf timber entirely away, and it will 

 scarcely consume itself without added fuel. For this 

 reason, engineers and architects still specify longleaf 

 timbers for certain kinds of construction, and are more 

 concerned in securing longleaf which meets their specifi- 

 cations, and is free from dry rot, than in securing a non- 

 organic substitute. Where both are supplied with auto- 

 matic sprinklers, buildings of the "slow-burning" or 

 ' millframe" construction type are insured at the same 

 rate as semi-fireproof buildings of steel construction. 

 Most millframe construction is built of longleaf timbers. 

 Wooden rafters for gymnasiums, halls, churches and 

 other public buildings, where the overhead construction 

 is in view from the interior are much more attractive 

 to the eye than steel beams. Longleaf is well adapted 

 to such uses, because of its strength, attractive appear- 

 ance, cheapness and the ease with which it can be obtained 

 in suitable dimensions. 



Longleaf is used for house building in enormous quan- 

 tities. It is particularly suitable where the same boards 

 appear on both inside and outside of the structure, the 

 reason being that it is strong and durable, holds paint well 

 and at the same time is attractive in the natural wood, for 

 its slow growth and large proportion of dense summer 

 wood give it a pleasing yellow and brown banded ap- 

 ])earance. Shortleaf Southern yellow pine is perhaps 



LONGIJCAF PINE ISKD I'OR PILINt; 



Tlie longleaf is extensively used for this purpose because it is particularly desirable for any heavy timber work, and because of its durability. 

 Weight for weight it is stronger than steel. It is also in demand for derrick booms, masts, flag-poles, trestle beams and timbers for buildings 

 of the slow burning or "mill frame" construction type. Its most .recent new use is for the frame work of targets for big gun practice in the 

 Navy. 



