November, 1909.] 



391 



Saps and Exudations. 



places the crotolaria or sensitive plant 

 may do much better than passion flower. 



It is easy to decide as to the most 

 suitable plant by planting one or two 

 trial plots. The following plants all 

 have advantages in different ways, and 

 if any one of them can be made to 

 entirely cover the ground in a short 

 time, say four or five months, its acqui- 

 sition will be a great gain to the estate 

 in improving the growth of the rubber 

 and in reducing the wages bill. 



Abrus precatorius, a native of India' 

 where it is used for cover, is leguminous 

 with a free creeping habit ; it grows 

 about one foot above the ground, and 

 the branches from one will spread to 15 

 or 20 feet from the main stem. The pods 

 contain six or eight seeds. The seeds are 

 bright vermillion, about the size of 

 buckshot, with a small black mark at 

 one end ; they are used as the karat 

 or standard weight for precious stones 

 and metal in India. 



Passiflora fcetida (passion flower 

 creeper), a creeping non-leguminous plant 

 having purple white flowers and yellow 

 fruits about the size of a walnut, grows 

 very freely on nearly all soils aud 

 smothers many other plants of a less 

 vigorous habit. This creeper never gets 

 more than about nine inches to a foot 

 high, and very quickly covers the 

 ground. It has to be kept from twining 

 round young rubber plants, but as it is 

 very soft this can be done at extremely 

 small cost- It is a native plant and com- 

 mon all over the Peninsula. 



Crotalaria striata and another species 

 of the same genus, Crotalaria incana, 

 are leguminous plants, possessing usu- 

 ally very numerous and large bacterial 

 nodules, and growing freely, when not 

 cut, to 7 or 8 feet high. It(C. striata) has 

 a yellow flower and a light green leaf, 

 and affords a good cover if not allowed 

 to grow high and scraggy. It should 

 be cut to a height of about 2 feet 6 

 inches. The cutting is not a costly pro- 

 cess, as it is only necessary to slash over 

 the tops, leaving the cut part to remain as 

 a mulch on the soil. The seed is obtain- 

 able in almost any quantity as a large 

 acreage is already planted. 



Tephrosia purpurea and T. Candida 

 are both vetch-like leguminous plants 

 which grow freely on almost any soil, 

 and give perhaps a better cover than 

 crotalaria. They must, however, be 

 slashed over at a height of 2-3 feet, and 

 not allowed to run up, otherwise the 

 light, and with it the weeds, will gain 

 an entrance. 



Mimosa pudica, the "sensitive plant," 

 a leguminous plant with red spherical 



flower heads and spiny fruits, is in many 

 ways the most suitable plant as yet 

 tried for cover. The chief reason which 

 makes it disliked by planters is the pre- 

 sence of thorns on its stems which are 

 unpleasant to coolies walking through it. 



The habit of this plant of shutting its 

 leaves in heavy rain and at night is au 

 advantage as no rain is lost and dew falls 

 on the ground. It never grows more 

 than about two feet high ; it persists 

 and makes a dense cover over the ground 

 when the leaves are not shut, i.e., when 

 the sun is shining and the plant is not 

 disturbed. It is, though a native of 

 S. America, common in all the planting 

 districts and one of the first plants to 

 take possession, and keep possession, of 

 the roadsides. 



In addition to these plants I have 

 recently been shown a creeping legu- 

 minous plant which was found by 

 Mr. H. P. Brovvell of Damansara Estate. 

 It is a species of Vigna, having dark 

 green leaves and making a dense cover 

 which refuses to allow any weeds to 

 exist- I have seen a patch of about half 

 an acre on Damansara Estate, and there 

 it appears to be the best plant for the 

 purpose of cover that has been used in 

 the Federated Malay States. 



The Future op Rubber. 



The Federated Malay States produce 

 about three-fifths of the tin supply of 

 the world, and in a few years' time 

 Malaya should supply a very large pro- 

 portion of the world's demand for rubber. 



In ten years (1919) presuming that 25,000 

 acres are planted annually during the 

 next five years (a very reasonable esti- 

 mate, considering that over 40,000 acres 

 were planted during the year in both 

 1907 and 1908), the rubber trees of the 

 Federated Malay States should yield not 

 less than 50,000 tons of dry rubber, 

 which at 3s. per lb. represent a value of 

 $144,000,000. This amount, should the 

 demand for rubber increase at the rate 

 it has beeu annually rising for the last 

 nine years, will probably at that time be 

 less than 25 per cent, of the world's 

 consumption. 



It is seventy years since the discovery 

 of vulcanisation by Goodyear made 

 rubber available for economic purposes. 

 It is now a necessity of civilised life, and 

 it is only by means of rubber that we can 

 solve the difficult problems of transport 

 and communication. Without it electric 

 wire insulation for telegraphy aud light- 

 ing, pneumatic and cushion tyres, and 

 the air brakes of railways would all be 

 impracticable ; and in the purposes for 

 which it is used in medicine and surgery 



