872 EXPERIMENT STATION RECORD. 



durable and ant proof. A copper sulphate solution was used and 4 wattle trees 

 varying from 4 to <*,.r> in. in diameter and 4<) to 56 ft. high were cut off and the 

 cut ends placed in tubs of the solution, the trees being supported in a vertical 

 position. With 2 of the trees the bark was peeled off. 



With both peeled and unpeeled trees the solution was rapidly taken up, sink- 

 ing in to a depth of 0.5 to 1 in. in the stem. The experiment is believed to be 

 too expensive to be of practical use. Nevertheless, poles from these trees have 

 been planted and the length of time they remain sound will be noted. 



The wattle industry in 1903 amounted to 12,135 tons. Neither Acacia mollis- 

 sima nor A. dealbata was found a satisfactory source for paper pulp. 



Forestry in Kiao-chou, Borgmann (Ztschr. Forst u. Jagdw., 37 (1905), No. 

 12, pp. 790-802). — General notes on the political and forestry conditions in this 

 German colony in China, with an account of the results obtained in planting 

 many species of broadleaf and evergreen trees. The only species of pine that 

 lias succeeded is Pinus thunbergii. The gingko tree (Gingko biloba) also grows 

 well. On the whole considerable progress lias been made along forestry lines 

 under rather unpromising conditions. 



The effects of the great frosts on the forests of northern India, E. R. 

 Stevens and E. A. Couethope (Indian Forester. 31 (1905), Xo. 8, pp. 1/35-W). — 

 Notes on the effects of the abnormal frost, during January and February of 

 1905, on the Dun and Saharanpur forests, with lists of the trees and shrubs 

 most injured and of those apparently unaffected by the frosts. 



Para rubber in Ceylon ( ilex/ Indian Bui., G (1905), No. 3, i>j>. 302-306).— 

 The results are given of observations on the growth of Para rubber in the 

 Royal Botanic Gardens of Ceylon with an account of the chemistry of Para 

 rubber, analyses being given of the fresh leaves and stalks, decayed fallen leaves 

 and stalks, and of the wood and branches. The data are quoted from a circular 

 of the Royal Botanic Gardens, Ceylon. 



Results of the experimental tappings of Hevea brasiliensis, W. R. Tro'mp 

 de Hass (Agr. Bah straits and Fed. Malay- stairs. ', (1905), No. 8, pp. 285-292; 

 Teysmannia, ti; (1905), No. 3. /,/>. 182-190).— This article gives the results of 

 experiments carried on at the Economic Gardens at Tjikeumeuh during 1900- 

 1904. 



In one experiment when the lengths of the incisions per square meter of 

 surface were 104, 320, and 740 cm., respectively, the corresponding- yields were 

 158, 384. and 407 gm. of rubber. It is thus seen that in the latter instance 

 when the length of the incision was more than doubled the increase was but 

 23 gm. of rubber per square meter of tapped surface. 



In another experiment the wounds were opened on both the upper and lower 

 edges and the resulting rubber yield compared with that obtained when only the 

 lower edge was cut Where both edges were opened the average yield in one 

 test was 238 gm. per square meter of surface as compared with 143 gm. when 

 only the lower edge was opened. 



Notwithstanding the fact, however, that more rubber can be obtained by 

 reopening both the upper and lower edges this increased yield does not cancel 

 the disadvantages of the incisions becoming so broad as to interfere with 

 proper healing. It is therefore suggested that if after the wounds have been 

 reopened 10 times they still yield much latex, it is advisable to continue the 

 tapping a little longer only on the lower edge of th% incisions instead of 

 working both edges. 



As to the time of year when the trees should be tapped, the author states 

 that in wet years it does not matter when the Hevea trees are tapped. In 

 normal years the best times for tapping are generally at the beginning and end 

 of the wet seasons. 



