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Possibilities of Cork Oak in U. S. ii| 



One is not apt to think of cork being a very important commodity 

 but in reality the importations of the United States of crude and 

 manufactured cork now amount to considerably over four million 

 dollars every year. Xot a dollar's worth of cork is grown in this 

 country although there appear to be no valid reasons why this should 

 be so. The cork-producing territory of the world covers practically 

 the whole of Portugal, extends eastward through the southern dis- 

 tricts of Spain known as Andalusia and Estremadura, and from there 

 northeast to include thousands of acres in Catalonia. Algeria, with 

 Tunis, ranks next in importance in bark production, followed closely 

 by southern France, including Corsica. Italy, Sardinia, Sicily and 

 Morocco also contribute a share. The total area covered by cork 

 forests is estimated at about four and one quarter million acres, 

 producing annually about 50,000 tons. A 

 large proportion of this is exported to the ' 

 United States. 



The cork of commerce, or ' ' corkwood ' ' as 

 it is usually termed, is the thick outer bark 

 of cork oaks, the most important species 

 being Quercus snher. The natural growtli or 

 virgin cork, as the first stripping of bark is 

 •called, is so rough, coarse and dense in texture 

 that it is practically useless. If it is removed 

 <'arefully further development of commercial 

 •cork takes place and after eight or ten years 

 is thick enough to remove. Subsequent strip- 

 pings follow at regular intervals of about 

 nine years. 



The first commercial crop of cork is ob- 

 tained from trees 35 to 40 years old, which 

 have at that time a circumference of about 

 ■2.11 feet and yield cork worth about 30 cents 

 a tree; the second crop, occurring between 40 

 and 50 years, is worth 58 cents a tree; the 

 third crop, at the age between 50 and 60 

 years, is worth 94 cents; the fourth crop, be- 

 tween 60 and 70 years, $1.40 ; the fifth crop, 

 between 70 and 80 years, $1.93; the sixth 

 crop, between 80 and 90 years, $2.56; the 

 seventh crop, between the ages of 100 and 

 110 years, $4.04 a tree; and the ninth crop, 

 between the ages of 110 and 120 years, $4.90 

 a tree; making a total of $19.92 a tree. 



Cork is stripped from the trees during July 

 and August and care must be exercised not to 

 injure the trees. By means of a long- handled 

 hatchet or a curved saw the bark is cut 

 through entirel.v round the base of the tree 

 and at a point just below the insertion of the main branches. These 

 two incisions are then connected by one or two longitudinal cuts and 

 the bai'k pried loose with the wedge-shaped handle of the cutting 

 tool. The larger branches are also stripped and yield thinner but 

 generally a finer grade of cork than do the trunks. The thickness 

 of the bark varies from! one-half inch to two and one-half inches, 

 while the yield ranges from forty-five to five hundred pounds, de- 

 pending on the size and age of the tree. The bark is allowed to 

 season for a few weeks and is then boiled and scraped. In this way 

 it is cleaned and purified, becomes more pliable and soft, and can be 

 tlattened out readily for packing and shipping. 



The uses of cork are very numerous. Besides the most common 

 one. as stoppers for bottles, there are also: seine and gill corks, 

 bobbers for fishing lines, instrument and fishing rod handles, bicycle 

 grips, pen holders, discs and washers, gaskets in lubricator cups, 

 life preservers, ring buoys, yacht fenders, shapes for mounting ani- 

 mal beads, buttons on fur coats, hat linings, glass polishing wheels, 

 cigarette tips, and many others. The waste in the manufacture of 

 these articles is made into composition cork, which can be used for 

 many of the same purposes as the original. Cork shavings are em- 



IXSIDE OF CORK FROM TREE GROWN 

 IN LOUISIAN.\ 



ployed in stuffing mattresses and boat cushions, in packing eggs and 

 other fragile articles, and in nialjing cork floor tiling. Cork flour 

 is one of the chief constituents of linoleum. Granulated cork is 

 widely used lor heat insulating purposes, often in the form of cork 

 board made up either with or without an asphaltic binder. The 

 low conductivity and great durability make cork almost ideal for 

 insulating cold storage and refrigerator rooms. 



It should be interesting to note what has been done in the way 

 of growing cork in this country. In 1858 the United States govern- 

 ment distributed cork oak seedlings to interested persons in several 

 states, but the Civil war interfered and the experiments were lost 

 sight of. In the latter part of the 80 's, 5,000 more seedling were 

 raised and distributed by the Division of Forestry to people in th© 

 South Atlantic and Gulf Coast states and als« 

 to a few growers in Arizona and California. 

 Repeated efforts to obtain reports of the 

 results obtained evoked no replies, so that 

 nothing definite is known regarding them. 



There are, however, quite a number of cork 

 oak trees of considerable size growing in 

 South Carolina, Georgia, Louisiana, and Cali- 

 fornia. So far as known there have been no 

 attempts to treat these trees so as to enable 

 them to form layers of conmiercial bark. 

 Such experiments are much needed to demon- 

 strate what quality of cork the trees grown 

 iu this country would produce. A number of 

 the trees have been successfully grown at the 

 forest experimental station in Chico, Califor- 

 nia, under direction of the University of 

 California, and individual trees have done 

 well when planted for shade and ornameutal 

 purposes in the Napa Valley, in California 

 State Park in Sacramento, and other points iu 

 central and northern part of the state. No 

 commercial plantations have been established, 

 however. 



AYithin the last year the United States 

 Forest Service has planted cork oak on a con- 

 siderable area on the Choctawatchee division 

 of the Florida National Forest. Nearly all 

 of the acorns came up, but those planted in 

 January were killed back by frost and later 

 sprouted from the stub. In January, 1912, 

 a shipment of 100 pounds of acorns was re- 

 ceived and planted on the Florida forest and 

 at Summerville, S. C, in co-operation with the 

 South Carolina Agricultural Experiment 

 Station. 



One of the chief difficulties involved in introducing cork oak into 

 this country lies in the poor keeping qualities of its acorns. The 

 acorns mature in Spain, Portugal, Algeria or southern France in 

 October or even November, and usually sprout the same wioter. 

 ilost of such acorns shipped to this country are therefore received 

 in a spoiled condition unless the greatest precautions are taken in 

 their packing. Charcoal has been found to be the best packing 

 material for preserving the acorns. 



The minimum temperatures which cork oak can withstand are 

 from 25° to 21° F. The maximum temperature is 104° F., and the 

 minimum precipitation which is necessary for its growth is about 

 20 inches. On a basis of these figures it is apparent that the poten- 

 tial range of cork oak in this country is quite large. To what extent 

 it will be economically profitable to produce our cork in this country 

 instead of importing it from Spain or Portugal is a matter which 

 can be decided only by actual experience. S. J. R. 



Maple is becoming almost as popular for making factory floors to 

 run trucks on as it is for making the trucks themselves. 



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