FORESTRY. 245 



was treated in this manner a penetration of from 2 to 4i in. was securel in 

 from 12 to 14 hours. With green fir the open tank method was used, but 

 otherwise the preliminary treatment was the same as for seasoned fir. After 

 12 hours of pressure, however, the oil was drawn off and the wood and retort 

 cooled for 12 hours, when pressure was again applied for a period of 12 hours. 

 It is found that the most oil is injected in the first 12 hours, but that the great- 

 est penetration takes place in the second 12 hours. The average penetration w'as 

 from 1 to 2 in. Both processes are said to require skilled help in order to pro- 

 duce satisfactory results. 



Preservation of wood against decay from soil, fung'us diseases, and insects, 

 E. Henry {Preservation des Bois contre la Pourriiure par Ic Sol, les Champi- 

 gnons et Ics Insectes. Paris and Nancy, 1907, pp. 96, pis. JO). — Noted from 

 another source (B. S. It., 19, p. 441), 



The Ceara rubber tree in Hawaii, J. G. Smith and Q. Q. Bradford {Hawaii 

 Sta. Bui. 16, pp. 7-30, pis. .'/). — An account of the Ceara rubber tree {Manihot 

 glaziovii) with special reference to its culture in Hawaii. The tree is discussed 

 relative to its habit of growth, root system, latex system, and seed. Suggestions 

 are given for Its culture including seed bed and planting practices, cultivation 

 and subsequent treatment, harvesting and preparing the rubber for market, 

 in which special attention is paid to methods of tapping the tree and coagulat- 

 ing the latex. The bulletin also contains the results of one year's experiments 

 in tapping rubber trees together with a discussion of the future of plantation 

 rubber and notes, by D. L. A^an Dine, on the insect enemies of the Ceara rubber 

 in Hawaii. 



The tapping experiments were conducte<l in two small groves of Ceara trees 

 on the island of Kauai, One of these groves w\as about fourteen years old and 

 the other nine years old. Detailed data are given of the tapping operations iu 

 each grove. Tapping experiments thus far indicate that there is a wide varia- 

 tion in the amount and quality of the latex yield -by individual trees, hence it 

 is advised that each tree should be tested relative to the quality and quantity 

 of its latex before the tree is two years old and that inferior trees iu this 

 respect should be taken up. There appears to be some relation between atmos- 

 pheric conditions and the flow of latex, although this relation has not thus far 

 been determined. Double the amount of rubber was procured by trickling 

 water containing ammonia over the tapping area over that by tapping without 

 the use of water. For this purpose a water bag holding about a quart of water 

 made with alternating narrow strips of porous oiled cloth or canvas was tied 

 around the tree 6 or 7 ft. above the ground, just above the tapping area. The 

 bag was left on the tree during the whole tapping season. It is believed that 

 the use of water will cheapen the cost of production and will practically do 

 away with the production of scrap or waste rubber. The opinion is advanced 

 that daily tappings for a period of two to four weeks or more w'ill yield much 

 better results than tapping on alternate days or longer intervals over a period 

 (if several months. In the present experiments daily tappings for a period of 

 nijie days gave better results than tapping on alternate days for double the time, 

 and the recovery of the tree was more rapid. Trees tapped either just before 

 or during the resting period did not leaf out as quickly as trees which had not 

 been tapped. 



Relative to planting operations in Hawaii, it is stated that by January, 1908, 

 400,000 rubber trees had been planted of which upwards of 90 per cent were 

 .1/. glaziovii. The remainder are Castilloa clastica and Hcvea brasilicnsis in 

 about equal projjortions. It is expected that tapping operations will soon com- 

 mence on some of these plantations. 



