[May, 1909. 



U7 



Saps and Exudations. 



an hour. The available labour on plant- 

 ations appear to be reasonably effective 

 in doing this work, and the amount of 

 training required in order to make the 

 cuts effectively and quickly is not 

 excessive. 



It requires less time to tap older trees 

 than the young trees, upon which our 

 work is done, and there is also less 

 danger of injuring the trees. We have 

 found that a good flow of latex can 

 be obtained from tapping done from 

 daylight until 8 a.m. or even later. 



From the experiments which we have 

 thus tar conducted it appears that one 

 man can tap about fifty trees per hour, 

 while another man can collect the 

 latex from the trees which would be 

 tapped in the same time by two men. 

 Since it appears from results which 

 we have obtained from tapping mature 

 Ceara rubber trees, that about one- 

 third ounce of dry rubber may be 

 expected as a daily yield, it is evident 



that three men should be able to ob- 

 tain rubber from mature trees at the 

 rate of about one pound per hour. The 

 data upon which this conclusion is 

 based have been carefully considered 

 and the estimate is probably not above 

 what may be expected. At any rate, 

 the results obtained in our experiments 

 indicate clearly that the Ceara rubber 

 tree in Hawaii will not only grow and 

 thrive, but will yield profitable returns. 



Further experiments will be carried 

 on in the microscopic examination of 

 sections of the Ceara rubber tree to 

 get a basis for determining the best 

 method of tapping. Several other 

 species of rubber trees will alsobe tapped, 

 and an elaborate series of fertilizer 

 experiments with rubber is planned, 

 We hope to be able to devise a method 

 of fertilizing rubber trees so as to secure 

 an increased flow of latex during the 

 tapping periods. — Hawaiian Forester 

 and Agriculturist, Vol, V., No. 12, 

 December, 1908. 



OILS AND FATS, 



A PLEA FOR SUNFLOWER 

 CULTIVATION. 



By W. F. Sutherst, ph.d., f.i.c, 

 Marist Bros.' College, Uitenhage. 

 The cultivation of sunflowers does not 

 pay in countries where land is dear and 

 consequently growth restricted, but 

 here in South Africa, where millions of 

 acres of land are still lying idle, there is 

 no doubt that it would pay. The intro- 

 duction of a new crop would also mean 

 fresh employment for the surplus 

 country population, as without moder- 

 ate export of agricultural produce, over- 

 production of maize, oats, etc,, is soou 

 reached. Not only the cultivation itself 

 needs labour, but the after-treatment 

 for the production of oil would also 

 utilise some of our unemployed. Most 

 of our agricultural produce when grown 

 requires no further treatment. Very 

 little care is necessary in sowing the 

 seeds, mere scattering them over the 

 newly-ploughed ground being all that is 

 required, the depth, as fixed by the 

 plough, never being too great in this 

 case. At the end of about six or even 

 four months the crop is ready for 

 harvesting. For opening up new ground 

 with the least trouble and quickest 

 returns its cultivation is ideal for the 

 Colony, as with the cash obtained one 

 can open up more ground. 



The seeds contain about 50 per cent, 

 of oil, i.e., without husk, and it would 

 save enormously if the seeds were first 

 decorticated, as the husks contain 

 practically no oil, and, making up about 

 40 per cent, of the whole, a great saving 

 in carriage is effected, as well as in the 

 further treatment of oil extraction. 

 The residual oil-cake is most nutritious 

 for all kinds of stock, especially dairy 

 cows and fattening stock. Little is 

 heard of it at present, as it is manufac- 

 tured in such small quantities, but once 

 started there is no limit to its uses. So 

 far very small quantities of oil-cake are 

 used in South Africa, as it has all to be 

 imported, and the cost is prohibitive, 

 except for owners of high-class stock. 



The composition of sunflower-seed cake 

 on the average is : — 



Fat ... ... 10 per cent. 



Albuminoids ... ... 20 ,, 



Carbohydrates 82 ,, 



Fibre 20 



Ash 6 



If the seeds cannot be pressed on the 

 farm, arrangements should be made for 

 the cake to be sent back to the farmer 

 for use on the farm, such as is done on 

 the beet sugar factories, where the 

 residues are returned, though these are 

 not nearly so nutritious. By far the 

 best plan would be for farmers to co- 

 operate and set up an oil crushing mill 

 of their own. 



