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the entrance of human beings into the forest, no matter how- 

 unintentional, cannot but give adverse results. To cite only one 

 example : Hilo grass seed carried into the forest from the out- 

 side 01"; a man's wet trousers or shoes will be dropped and will 

 germinate in small openings in the forest or along a trail and 

 will spread to the great detriment of the undergrowth. 



Economy in Forest Protect'wii. 



The economical aspect of forest protection should not be neg- 

 lected. It is much cheaper to protect what we have in the 

 shape of a water-conserving forest than to ignore it entirely and 

 hereafter be compelled to reforest by artificial means. 



\\'hen taken at the start, at the very beginning of deterioration, 

 the native forest when protected by suitable fencing to keep out 

 stock, will often recover to a degree sufficient to perform the 

 functions of conserving water. The later this protection is 

 given, however, the more difficult will it be for the forest to come 

 back, especially if foreign growths have been allowed an entrance. 

 It pays therefore to tackle the problem at the very beginning of 

 trouble, or better still, before the trouble begins. 



If deterioration has been complete, the job of artificial re- 

 forestation is most difficult. To be sure, the native koa tree can 

 be used for this purpose to some extent in certain situations, such 

 as well-drained soils, where there is a moderate amount of mois- 

 ture. The koa is easily handled in the nursery and gives quick 

 results in the way of growth, but its extensive use is hindered by 

 the difficulty of 'securing an abundance of seeds because of a 

 destructive moth borer which attacks the seed pods while they 

 are ripening. 



The difficulty of establishing an ohia lehua forest by artificial 

 methods of planting has already been explained. It has been 

 attempted also to point out the complicated evolution of our wet 

 forest, the peculiar method by which it perpetuates itself, and the 

 mtricate natural association of plants in such a forest, which 

 serves as an ideal protection forest. To allow such a natural for- 

 est to disappear and attempt to replace it generally with a new 

 forest, established by artificial means, seems almost like flying 

 m the face of Providence. 



Artificial reforestation is at best a very expensive undertaking 

 and a great deal of experimentation would first have to be under- 

 gone before one could find the happy combination of self-per- 

 petuating trees, shrubs, and undergrowth which would live to- 

 gether and thrive under the peculiar conditions found in our 

 mountains and perform the function of conserving the runoff 

 in a better and more satisfactory manner than our present na- 

 tive forest. 



In some situations, where on account of poor drainage or worn- 

 out soils our native tree species will no longer thrive, they may 

 have to be replaced with more vigorous introduced trees. With 



