396 APPENDIX 



in this brush and the young oak, overwhehned by such a thicket, does not receive the 

 quantity of Ught which one would expect in such open stands. Seeds are often scattered 

 by the birds, chiefiy by the doves; in mixed forests of oak and pine often the oak seed- 

 lings are found in the neighborhood of the pine trees because the doves love to perch 

 on the branches of the pine, which are the largest trees of the stand, and from there let 

 fall the acorns which they have transported. Often seedlings are so suppressed by the 

 heather that they cannot develop, remaining poor and stunted and finally often dis- 

 appearing altogether. It is therefore necessary to take care to search out the oak 

 seedlings in the midst of the brush and free them. 



Cutting Back the Young Poorly Formed. — The seedling which appears to have 

 suffered from the heather cover to such an extent that its vitahty is injured should 

 be cut level with the ground, and after this operation the heather should be cut for a 

 distance of 1 to 2 feet around the shoot. The sprouts which develop on this little 

 stump will have even more vigor than do seedlings. Moreover, if in a stand of cork 

 oak which has already attained a height of 4j to 6 feet, but whose growth appears slow, 

 it is much better to cut them back in order to obtain good sturdy shoots in their place. 

 These shoots have just about the same value as seedhngs. This cutting back, it is true, 

 has the objection of encouraging the formation of sprouts; the collection of cork oak 

 being difficult on sprouts, it is better to choose between them when they have attained 

 the height of about 6 feet and leave the best sprouts and cut the others. 



Division of a Forest of Cork Oak into Compartments. — Work such as this 

 enables the improvement of cork-oak stands to favor whose regeneration there is no 

 other method applicable. To execute the freeing and cutting back of seedUngs syste- 

 matically the forest should be divided into some fifteen compartments so that each one 

 can be gone over every year to free the seedlings, cut back the poor sprouts, and thin the 

 sprouts when they are too numerous. It would be a good plan to have this work 

 coincide in each compartment with the removal of the mature oak. The cost of this 

 work is small in comparison with the benefits received and the owner should pay for it 

 without doubting its advisabihty. 



Precautions to Take against Fire. — The existence of brush is a perpetual danger 

 of fire. ... It should be remarked, however, that the cork is an excellent insula- 

 tion and that the violence of the fire is rarely enough, in France at least, to kill the cam- 

 bium of the oak when they are protected by a sufficient thickness of tissue. The oak 

 recently peeled, however, is very susceptible to the slightest fire. ... To avoid 

 fires in any part of the forest becoming veritable disasters, it is therefore necessary to 

 make sure that the trees recently peeled should not all be grouped in the same range. 



In order that the cork of a tree should attain the thickness demanded by commerce 

 (27 to 29 miUimeters), the period varies according to the cUmate: 12 years in Algeria, and 

 15 to 28 years in France. Taking for granted that the period of 15 years should be the 

 one indicated by investigation, the forest should be treated as follows: 



Divide it into fifteen compartments and the first year bark all the oak in Compartment 

 No. 1, the second year all those in Compartment No. 2, etc., and the fifteenth year all 

 those in Compartment No. 15. In the sixteenth year the oak in Compartment No. 1 

 will have had 15 years of growth and reached the proper thickness. One can then pro- 

 ceed with new felling operations on trees of this compartment and continue indefinitely. 

 But if, by misfortune, fire has broken out in a compartment where the bark has been 

 removed from aU the trees, every one will be destroyed and the compartment will be 

 ruined without hope even of natural regeneration. Under such circumstances it would 

 have been better to adopt another combination. The number of years necessary for 

 the growth of the bark is divided by 3. For example 15/3 = 5; if the forest is divided 

 then into the number of parts given in this quotient, each compartment would be 



