juLY, 1908.] 



8 



Saps and Exudations, 



rate. It is to be noted that West Indian 

 labour has to be taught first before it 

 can be calculated upon. 



The preparation of ' scrap ' rubber 

 would cost probably one-third less than 

 ' sheec' 



Castilloa as a rubber has done well in 

 all parts of Trinidad, and appears to 

 suit the conditions of soil and climate. 



The supply of seed is so plentiful that 

 the sales made by the Department are 

 now merely nominal. Moreover, by birds 

 carrying off seed the tree is being dis- 

 tributed widely through the natural 

 forest, where it grows readily. 



Hbvea, or Para Rubber. 



The progress made in Hevea planting 

 has been much encouraged recently by 

 the prices obtained for Ceylon produce. 

 The demands upon our resources for 

 seed and plants is now more than we can 

 meet ; hence, a considerable number of 

 importations have been made with a 

 success varying from 2 per cent- to 00 

 percent. Various methods of packing 

 have been tried. From personal experi- 

 ence it appears better to take the chance 

 of seed transport rather than to import 

 plants, even in Wardian cases. 



Some twelve years ago I advocated 

 strongly in the Trinidad Bulletin the 

 planting of Hevea. One planter planted 

 a considerable number, and to-day his 

 trees are seeding freely and he is making 

 an excellent returnfor seedaud seedlings, 

 and has thus provided for a future 

 supply of home-grown seed, which will 

 probably meet future demands. The 

 trees in the lands of the Botanical Depart- 

 ment gave a fair supply of seeds, from 

 which several thousands of healthy 

 plants have been realized. All of these 

 have been readily sold. 



Eight or ten estates are now planting 

 Hevea, and this number will probably 

 be doubled during the coming year. 



With regard to the ability of Trinidad 

 to produce first-class Para rubber, I 

 submit to the Conference specimens of 

 various forms from the older trees of the 

 Botanical Department. These speci- 

 mens have been produced by two trees 

 of the fiist consignments sent out by 

 Kew over thirty years ago. The first 

 tree gives rubber decidedly yellow in 

 appearance, while the second tree gives 

 rubber which on first coagulation is pure 

 white, aud probably differs considerably 

 in composition from the first. 



Two methods of collection have been 

 adopted. The first is to collect all 

 latex possible and set it to coagulate 



naturally ; the second is to roll up the 

 remainder of the rubber which dries 

 in the cuts to a ball. 



It is found that a second and even a 

 third flow can be obtained from the 

 same cuts, if the rubber is allowed to dry 

 for some eighteen to twenty hours in the 

 cut ; for when it is removed a new flow 

 takes place from those cells, which have 

 been prevented from closing by the ad- 

 hering rubber. 



That the rubber is of good quality 

 is shown by the specimens now sub- 

 mitted for examination. The latex 

 when set to coagulate is simply strain- 

 ed through fine wire gauze with a 

 minimum of added water, and then left 

 in a soup plate or glass cell in 

 a cool place. Twelve to twenty-four 

 hours afterwards there can be removed 

 soft sheet rubber perfectly coagulated. 

 It may then be pressed into biscuits, in 

 a copying press or by other suitable 

 means. Rubber thus treated will dry 

 quicker than if left to drain by itself. 



At the Experiment Station, Hevea 

 trees eight and a half years old do 

 not as yet yield rubber in quality or 

 quantity to pay for tapping, although 

 the trees are some 35 feet high with 

 stems 6-9 inches in diameter. Our oldest 

 tree has a diameter of 2 feet 3 inches at 

 4 feet from the ground, aud gave a crop 

 of over 4,000 seeds during the season 1906. 



Prom our tapping experiments it may 

 be estimated that 3 to 4 lb, of rubber 

 could readily be taken from this tree; 

 but, as it is depended upon for purposes 

 of seed, it has been deemed better not to 

 hazard productiveness by tapping too 

 heavily. 



Two young trees raised from seeds 

 brought down by Dr. Bovailius, from the 

 interior of South America, are growing 

 slowly and appear to be somewhat 

 different from the kind first introduced, 

 but, as they have not as yet flowered, it 

 is impossible to decide their affinity. 

 They are said to be suitable for growth 

 at higher elevations or in cooler climates 

 than the ordinary varieties of Hevea, 

 but this remains to be proved. There is 

 no doubt a great future for Hevea plant- 

 ing in Trinidad, the only drawback 

 being the length of time the trees take 

 to reach maturity. This state of matur- 

 ity most assuredly will be fixed at 

 different ages by individual growers, 

 probably gauged by financial reasons. 



Trees can be tapped at an age when 

 tapping is sure to injure them, therefore 

 cropping must always be conducted 

 with greatest care, as serious wounds 

 most inevitably prove prejudicial to the 

 life of the tree, 



