^VoL. Vlir. Xo. 183. 



THE AGRICULTUEAL NEWS. 



14* 



YIELD OF PARA RUBBER TREES. 



The yields that ma}' be expected from rubber 

 trees at given ages x>i" sizes have been the subject of 

 much discussion, and figures that liave.been placed on 

 record from numbers of sources show i\vide difference. 

 Wild rubber trees (Heva hrasUien-'^i.sjiTi the Brazilian 

 forests are reported to show returns vai-ying from 1 ft. 

 to a maximum of as much as 10 lb. per annum. The 

 average return obtained under those ll-onditions, how- 

 ever, is believed to lie between 2'2 It), and 3 3 lb. per 

 tree yearly. This question is discussed in a recent 

 nvimber of the Iiul'iH-Ridiher World, and a large mass 

 of figures are given showing the quantities of rubber 

 yielded on numbers of planted est^ates in the East 

 Indies. 



It is [jointed out that the yield.s of produce oljtained are 

 infiuenoed l:>y a number of factors, i.e., the character of the 

 soil, altitude, or climatic condition.s, the closeness or width of 

 planting, the frequency of tapping, the method of tapping, 

 ■dffld the care with which the latex is handled. It is added 

 that the age at which tapping may be commenced is deter- 

 ifiined more by the size than by the age 6f the tree ; trees 

 with .short trunk.s of large girth may be more productive 

 than taller ones of less girth. 



A large amount of additional data isi*till required before 

 reliable statements can be made as to : yields that may 

 definitely be expected from rubber trees under certain condi- 

 tions. Towards this end, records are needed from numbers 

 of weU-managed plantations, showing the returns obtained 

 from a definite number of rubber trees, of uniform size and 

 age, tapped the same number of times, by the same system, 

 and with the same method of treating the latex. 



The latest edition of Mr. Herbert Wright's book ' Hevea 

 Jhrisili'ensis ' contains a quantity of data relating to yields 

 on rubber estates, although no effort is^iiiade to connect 

 average yield with age. One table in the book shows the 

 returns from twenty-three estate.s, on Which, in one year, 

 166,710 Para trees gave 21.5,93.3 B). of rubber, or an average 

 of 1'235 R). per tree. The e.state with the lowe^5t average 

 showed a mean return of 0'32 lb. per tree ; the highest aver- 

 age on any estate was 5'.") lb. per tree. Six estates showed 

 average yields of 2, 2'2, 3-2, 3'25, 3'-5, and o-5 ft), per tree 

 respectively. Figures relating to another list of estates 

 described by Mr. Wright indicate a mean return of 2'.52 ft), of 

 rubber per tree. 



The report of the Anglo-Malay Rubber I'ompany, Ltd., 

 for 1907, contains some interesting iterhs. On one estate, 

 a, plantation of Para trees, aged 7 to 8 years, yielded a mean 

 return of 3'76 ft), of rubber per tree ; on a second estate, 

 however, trees from 9 to 10 years old gave an average yield of 

 only 2 '95 ft). Again, on a third estate, where the greater 

 number of trees were from 6 to 7 years old — but a few were 

 "aged 9 to 10 years — an average of 3'32 lb. of rubber was given. 



The following data — given in the Indiii.-Ruhher 

 Wiirhl — relate to the number and age of trees tapped, 

 and to the returns obtained, on the Malay estates of 

 the Bukit Rajah Rubber Co., Ltd., and have been 

 compiled from the reports of the company: — 



Year ending March 31, 1906. — Trees tapped, 34,157 ; 

 yield, 33,203 R.; average age of trees af'tnd of period, 6"23 

 years; average yield of tree, 0'97 ft). 



A'ear ending March 31, 1907.— Trees tapped, 88,341 ; 

 yield, 118,982 ft).; average age of trees, .5'94 years; average 

 jieldr L345 ft).. 



Year ended March 31, 1908.— Trees tapped, 89,29.5; 

 yield, 163,521 ft).; average age of tpees, 7-27 years; avijrage 

 yield, 1'83 lb. of rubber. ' i' 



Some definite information is ^iven in the report of the 

 Highlands and Lowlands Para Rubber ("ompany, Ltd., for 

 1906. It is stated that on one,, block of 16 acres, 807 

 Hevea trees, planted 30 by' 25' leet, were tapped, during 

 three periods of the year mentioned,' with the results : 2,500 ft). 

 of rubber at the first, 1,469 11. at;,tJie second, and 1,773 R. 

 at the third tapping, or a total 'irt,742 lb. — an average of 

 7 "01 ft), per tree for the year. ■ 



During the business year 190'6-7, the Federated Malay 

 States Fiubber Company, Ltd., cplfceted 32,175 lb. of rubber 

 ffom 12,335 trees, or an average return of 2-60 ft. of rubber 

 per tree. These trees were planted,,at fairly wide distances. 



From all the data given in the article it would 

 appear safe to estimate a return of not less than 2 lb. 

 per "tree annually, from trees, about 8 years old, with 

 reason to expect a larger yield with increased age. 



PLANTING CASTILLOA RUBBER, 



Castilloa rubber has received some attention in 

 a number of the West Indian islands, and, on the whole, 

 the trees have made good growth, although it would seem 

 that this variety is not likely to give so satisfactory 

 a yield as the Hevea or Para rubber. The following note, 

 referring to the distance apartat which Castilloa trees 

 may best be planted, and the culture of catch crops 

 between the rows, is extracted from an article on the 

 subject contributed to Tropical Life of September last 

 by Mr. William Fawcett, B.Sc, late. Director of Public 

 Gardens and Plantations, Jamaica : — 



The distance at which Ca.stilloa trees should be planted 

 at first depends upon whether they are to be grown with 

 bananas or other catch crop, or alone. If the soil is suitable 

 for bananas, and the locality one where it will pay to grow 

 them, no other catch crop is anytinng like as good. The 

 bananas should be planted in ilarch at distances of 15 feet 

 apart, and the Castilloa seedlings may be put out about 

 September, each seedling in the centre of four banana plants, 

 or, if the cultivator or plough is tised to keep down weeds, 

 the Castilloa must be planted in the banana rows between, 

 the bananas. The bananas may be grown for three or four 

 years, and then they .should be gradually thinned out as the 

 Castilloa trees spread their branches. If bananas are not 

 suitable, corn (maize) and pigeon peas (Cajanus indicws) may 

 be used as catch crops and temporary shade. The fields 

 should be lined out in March, and stakes put in to mark 

 where the Castilloa plants are to be put out. Then the 

 pigeon peas should be sown so as to leave a clear space of 

 4 feet round the stakes, and the corn not nearer than 7 feet 

 TJie pigeon peas will not last more than two or three years, 

 but by that time the young Castilloa plants will not require 

 any more nursing. The corn will not interfere with the 

 Castilloa if kept at a safe distance, and if there is a rnirket 

 for it, the returns will help to pay expenses. Even if there 

 is not a market for the pigeon peas, they will increa.se the 

 nitrogen content of the soil, besides forming a slight shade 

 for the rubber. The cultivation of the soil will be of the 

 greatest benefit to tlie growing rabber plants. If no catch 

 crops are to begrown, the distance for the rubber plants may- 

 be 6 feet at first, to be thinned out eventually to 18 feet 

 'apart. 



