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BULLETIN 53, HAWAII EXPERIMENT STATION 



Experiments in propagation of the tree fern show that not only 

 the crowns, but also the large and the small lateral shoots, and un- 

 developed buds on the trunk, may be successfully planted. An aver- 

 age of three plantings or sets can be secured from each mature tree 

 fern. 



The station developed a method for determining the rate of growth 

 of the tree fern. This method showed the vertical growth to be only 

 4.35 inches a year, which means that it would require 20 years for a 

 tree fern to reach sufficient size for starch production. Such a slow 

 rate of growth makes it commercially impracticable t© plant cut- 

 tings from different parts of the tree fern, or to build permanent 

 roads or fences for the purpose of obtaining the raw material. 



The high costs involved in securing raw material preclude the 

 possibility of the starch becoming a competitor with the common 

 commercial starches, and likewise limit its use to special purposes 

 commanding a high market price. With the cheap labor available 

 in many of the tropical countries, however, the costs could be re- 

 duced to a fraction of what they are in Hawaii. 



In chemical composition the core of the tree fern is similar to that 

 of other starch crops, especially of edible canna. 



Morphologically, the starches of the different species of tree ferns 

 are very similar, differing chiefly in size, but also somewhat in shape. 



Tree-fern starch is used both as a food and for laundry purposes. 

 It is markedly superior to cornstarch for laundry purposes. In Ha- 

 waii the starch is used chiefly in the preparation of poi. 



Although the development of the tree-fern starch industry is 

 seriously handicapped b}^ the high cost of securing the raw material, 

 data have been secured which would make possible, in cases of 

 emergency, the production on short notice of sufficient starch to meet 

 the need of the local population. 



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