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Show CorkCan Be Grown on Waste Lands WWM'k' ' '-'f";i Of Southwest U. S., Survey Reveals W&X. "A J k ' -1 This Vital Material Is Now Imported From Spain and Portugal CORK OAK, attractive evergreen or "live oak" that will serve about the same ornamental and shade purposes pur-poses as other live native oaks, yields a product that, despite the many substitutes developed, still remains a highly critical material in wartime. The cork oak is being grown in many different sections of the coun try. The map given below shows . some of the sections where cork oak trees are now in production. The cork oak is adaptable in a considerable consider-able portion of this country. The limiting factors to its growth, are drouth, that is rainfall below 20 inches per year, poor drainage and severe winter temperatures. Cork oak has withstood a minimum temperature tem-perature of five degrees below zero at several places along the Atlantic seaboard. It is believed to have sur- j vived even lower temperatures in I the mountains of Spain. If the future use of cork expands, .even in peacetime, a shortage of I this versatile material may develop. I The development of molded cork insulation, in-sulation, the expanding use of cork for floor and wall coverings, and the increasing need for engine gaskets, as well as such well-known products as bottle stoppers, crown caps, handles han-dles for fishing rods and other im-lements, im-lements, shoe insoles, linoleum, friction pads, etc., indicate that the total demand for cork products is likely to increase rather than decrease de-crease in the future. One substitute for cork has been developed at the USDA Northern Regional Re-gional Research laboratory at Peoria, Peo-ria, 111. It is made from the pith and fibers of farm wastes, together with animal or vegetable glues and sugars, apple syrup or glycerine. By cutting pith into fine particles and incorporating these in a liquid composition that when set, hardens to an elastic body, a product has been produced that closely duplicates dupli-cates the physical structure of cork. Farm crops with pith particles suit- ! able for this purpose are sugarcane, cornstalks, peanut hulls, and similar sim-ilar material. During normal peacetimes about 160,000 tons of cork is imported annually. an-nually. Domestic Cork Prospects. .. The total potential cork area, In the Southwest alone, covers more than half a million square miles. Out of this area, more than 100.000 square miles or more than 70,000.-O00 70,000.-O00 acres are available for cork oak plantings. This represents land that has no economic crop at present, but is suitable to become the center of a great cork industry. The number of cork oak plantings that can be made each year is limited lim-ited to the domestic acorn crop. Acorns must be kept in cold storage xiniu piamea in oracr to preserve their viability. So far temperatures of 36 to 38 degrees have proven satisfactory. sat-isfactory. The largest grove of trees in the United States is in Bidwell Park. Chico, Calif. Here more than 600 cork trees are thriving from a planting plant-ing made in 1904. A large nursery at Superior, Ariz., where 50,000 cork seedlings are grown annually, has been put into operation recently. It will still take many years before be-fore domestic cork trees can supply even the cork needed in making engine en-gine gaskets. The crankcase and oil compartments of most engines are sealed with cork gaskets. With engines en-gines playing the part they are today to-day in our combat as well as defense activities, cork gaskets become a vi- Nfc?:. 4 ' ';. ; y. A 'f , 'yy 'ffs Jy A o V. J? j ' y y ' ' ' fy , 'f ' ' W , "A v V rz y r yu y I - ' J Method of peeling bark from mature cork oak on Napa state hospital grounds, California, Is demonstrated by George Grecnan, forestry expert. He uses a tool resembling a huge chisel. Notice the trunk behind Greenan, which has already been stripped. tal wartime necessity. It mav not I for nlantini?. These trees arp heinp! " be beyond reason to expect at present pres-ent rate of plantings, that within 15 years, this need will be met in the United Stales. California leads in cork oak acorn production. In 1944 there were harvested har-vested 16,000 pounds in this state. Acorns ripen during November, De-I De-I ccmbcr and January, usually in three different stages. The first of the crop is poor, later it is better, and those collected after December 15 are generally best. Thorough Study Made. An exhaustive study of soil, climate, cli-mate, rainfall and temperature conditions con-ditions in the United States has been made and this data compared with that of the cork-producing sections of Portugal. From this study, the map given herewith has been prepared. pre-pared. While this physico-geograph-ical map serves as a guide in planting plant-ing cork trees, seedlings have been distributed to persons outside of this theoretical cork area. It is entirely possible some sections indicated as less desirable for growing cork may produce satisfactory trees. A large quantity of corkwood, harvested har-vested in California during the past few years, was sent to the research laboratory of the Crown Cork and Seal company for study and evaluation. evalua-tion. Careful examination and tests indicated that the domestic cork is equal in every way to the imported article of the same grade. For more than 2,300 years the world's supply of cork has come from the shores of the western Mediterranean. Many of these groves are suffering as the result of neglect, disease and insects, a condition con-dition that is not present among the American stands. In order to standardize the quality qual-ity of cork produced, bark samples are removed from trees in selected areas for exhaustive laboratory testing. test-ing. Samples of soil from under the trees have been collected and examined. ex-amined. These vary considerably and include clay loam, sandy loam and rich garden loam showing that cork oaks grow well on a wide variety vari-ety of soils. The fact that cork oaks, In widely scattered places, have thrived for from 60 to 85 years and have grown into beautiful trees shows conclusively conclu-sively that the United States can produce this valuable tree. Many of the large cork oaks in the South do not bear acorns, and efforts are being made to cause these trees to fruit, because the acorns are needed Map showing areas of United States best suited to cork oak culture. .Great sections of semi-desert land, now practically worthless, is well adapted to growing cork, foresters state, after extensive research into soil, rainfall and temperature requirements of this tree. given special care and scions from prolific California cork oaks have been grafted to some of them. Soil and Climate Needs. The successful culture of cork oak is no more difficult and not greatly different than the culture of the more common ornamental trees. Cork oak will survive in localities where the winter minimum temperature occasionally occa-sionally drops to zero, or even a few degrees below zero If the trunks of the trees are protected for four or five years until the bark becomes corky. High temperatures will not harm the tree as it is growing vigorously vig-orously in parts of California where maximum temperatures of 115 degrees de-grees Fahrenheit are not uncommon. uncom-mon. Cork oak is said to grow best and produce the highest quality cork in its native habitat on well-drained, sandy-loam soils that are not limey in nature and often rather low in fertility. In the United States, however, how-ever, trees are growing in many different dif-ferent soil types, including clay soils, peat soils and limey soils. The.wa-r The.wa-r ,.. , W,AW, i " r ; i , 'Cz si'-yy ? i -. -x y - i' 'vj '-''' : y . ' .:'. ' ' . ... " v These cork oak acorns were grown near Winnesboro, S. C. Many big trees in the South do not bear acorns for some reason. This is unfortunate, unfortu-nate, considering the acute need. ter table seems more important than the soil texture, for plantations made where the water table is less than six or eight feet below the surface sur-face have failed. A surface soil that becomes hard and baked is not a good soil for cork oak as attested by failure of trees planted in such soils. Cork oak naturally grows in sunny locations and docs not succeed well in shady situations. It will start growth when partially shaded and even seems to prefer partial shade when young, but to make normal development it must, after a few years, have nearly full-sun conditions. condi-tions. This need for much light may eliminate "fog belt" areas of the West coast. If drainage is good cork oak grows well in parts that are sprinkled each day or along streams where the soil is continually moist. On the other hand, it also grows well, but more slowly, where the annual precipitation precipi-tation is as low as 20 inches per year. The cheapest and perhaps more satisfactory method of establishing cork oak is to plant the acorns directly di-rectly in well-prepared seed spots as soon as they are received. The seed spots are prepared by removing remov-ing all Vegetation from a circle a yard in diameter, then pulverizing the soil to a depth of six inches. The seeds should be planted in moist soil and covered to a depth of about one inch. This may be done at "any time l during the fall, winter or spring. |