NAVAL STORES 167 



SOURCE OF PRODUCTS 



The naval stores industry is confined to eight states of the southeast, 

 bordering the Atlantic and Gulf of Mexico from North Carolina to Texas, 

 inclusive. Probably at least 90 per cent of the total products is derived 

 at present from the longleaf yellow pine {Pinus palustris). Cuban or 

 slash pine {Pinus heterophylla) is also tapped. Other Southern pines 

 such as the loblolly and shortleaf pines yield a resinous exudation when 

 tapped, but there is not a sufficient quantity of resin available to make 

 their exploitation for this purpose commercially profitable. Western 

 yellow pine may be developed in the future in the southwest, California 

 and in Oregon, and experiments have demonstrated that the resinous 

 flow is sufficient to justify commercial development. However, there 

 are many practical and commercial difficulties in the way of present 

 development, particularly the labor question and a market for the 

 products. 



Resin is stored in resin ducts which are peculiarly large and abundant 

 in longleaf and Cuban pines. The resin ducts form in the region of the 

 cambivmi layer. When exposed by a cut or chipping streak the exuda- 

 tion of their resinous secretion is permitted. Each cut stimulates the 

 formation and development of other resin ducts above the incision or cut 

 and an area of from 2 to 3 in. above the cut is affected in this way. 



Experiments have shown that over 67 per cent of the total resin 

 flow after each exposure or chipping occurs within the first twenty-four 

 hours. Oxidation and crystallization of the resin at the mouths of the 

 resin ducts causes them to be clogged, so it is necessary to make fresh cuts 

 from time to time to renew the flow by opening new ducts. Chipping is 

 consequently done every week. At the expiration of this period prac- 

 tically all flow from the previous cut has ceased. If the weather suddenly 

 turns cold it is likely to retard or even completely stop the flow of resin. 



ANNUAL PRODUCTION 



North and South Carolina were formerly and for a long time the most 

 important centers of production of naval stores. When the virgin 

 longleaf timber of these states was largely bled for turpentine, Georgia 

 became the center of production. For the past two decades, Florida 

 has been the great producing center of naval stores. The largest 



