CORK OAK—RYAN AND COOKE 
indicates several thousand cork trees 
are growing in this State. Excellent 
specimens of young cork trees 6 to 8 
years old are now growing in Califor- 
nia, Arizona, Texas, Arkansas, Ala- 
bama, Mississippi, and elsewhere in 
the South. In all the cooperating 
States encouraging progress has been 
recorded indicating that the cork 
tree can be grown successfully when 
planting conditions are favorable. 
Since the initiation of the McManus 
Cork Project more than 600 cork 
trees have been stripped of virgin 
cork. Most of these trees are in 
California but cork has been removed 
from approximately 20 trees in Ari- 
zona and the southern States. This 
cork has been manvfactured into 
cork products and given standard 
tests. Composition cork and cork- 
board insulation manufactured from 
the domestic product were of excel- 
lent quality. Growth of reproduction 
cork on the stripped trees is very satis- 
factory. Almost 1 inch of second 
growth is obtained in 6 years on 35- 
year-old trees. With older trees the 
growth was even greater. The follow- 
ing table gives a summary of cork 
stripping by years: 
Number | Yield of 
Year of trees cork 
stripped | _ (Ibs.) 
14 OP er Secenek 248 10, 561 
DOA rete aos ene « Reta aate 47 2, 142 
MQ AD Mpa at serene ci eretene 63 3, 466 
SAS ep ienste 2 sola ones on 46 D5 
NOAA ray tata eceveins mises ote 54 35216 
1A Oe chaos omaasrcte ene 58 3, 538 
NSA Greer nr ect che 46 2, 882 
OATES hye eae a hhes 61 2, 803 
Geographic and Economic Studies 
Although there are upward of 4,000 
old cork oaks and nearly a million 
new plantings scattered in 24 States, 
we must face the fact that the cork oak 
is not yet grown in the United States 
in commercial quantities and that we 
are virtually without experience in its 
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359 
growth as a crop. Therefore, before 
a cork-forest industry becomes a reality 
in this country, there is much to be 
done in the way of organized research 
and systematic planning in order to 
establish the essential foundations for 
such an industry. 
At this particular stage of develop- 
ment, the most essential requirement 
for the botanic and economic success 
of a cork-forest industry appears to be 
the selection of suitable areas in which 
to grow the trees in order that the 
cork oak in the United States will be 
provided with a geographic ecology 
identical with that of the Mediter- 
ranean region and will not be required 
to adapt itself to a new or foreign 
climate, but will be free to grow and 
produce in response to the same laws 
of Nature as those prevailing in its 
natural habitat. A hypothesis as to 
such suitable areas was developed 
after the completion of a compre- 
hensive geographic study of the natu- 
ral distribution of the cork oak in rela- 
tion to the climatic factors of temper- 
ature, rainfall, and soil, which is 
described in detail in “Some Geo- 
graphic and Economic Aspects of the 
Cork Oak” (3), from which the 
following is condensed. 
Geographic Distribution of the Cork Oak 
The world’s commercial supply of 
cork, which averages, at the present 
time, about 350,000 short tons per 
year, is grown in the approximate 
5,015,000 acres of cork oak forests 
bordering the Mediterranean Sea. 
The entire area is known as the 
Mediterranean region and comprises 
Portugal, Spain, France and Corsica, 
Italy, Sicily and Sardinia, Tunisia, 
Algeria, French Morocco and Spanish 
Morocco. The total cork-forest area 
of this region is approximately 7,950 
square miles. 
The locations of the cork-growing 
areas within each Mediterranean 
country are shown in figure 1 and the 
facts and figures of distribution and 
production are listed in table 1. 
