172 THE APRICAN RUBBER TREE 



ill its behaviour on tapping. It has been pointed out 

 abeacly that the latter tree can be repeatedly tapped 

 for long periods, whereas Euntumia trees yield practically 

 all their available latex at a single tapping and can only 

 be tapped once or twice a year. The methods employed 

 for Para trees cannot, therefore, be used for tapping 

 Funtumia elastica. The bark of the Funtumia tree 

 is also much thinner than that of the Para tree and is 

 consequently not so suitable for tapping purposes. 



Cultivated Funtumia trees are not usually tapped 

 until they have attamed a girth of at least 18 in. at 

 3 ft. from the ground, and the method of tapping most 

 commonly adopted is the double-herringbone system 

 (see p. 66). The incisions are generally restricted to 

 one-half of the tree, and the two halves are tapped alter- 

 nately. In some cases, however, each set of incisions 

 is restricted to one-third of the circumference of the stem, 

 and two vertical columns of untapped bark are left be- 

 tween them at opposite sides of the trunk in order to ensure 

 that the vital functions of the plant are not interrupted. 

 The incisions are frequently carried to the top of the 

 stem; but in Southern Nigeria regulations were intro- 

 duced in 1910 whereby cultivated Fimtumia trees are not 

 to be tapped to a greater height than 10 ft. from the 

 ground. The lateral cuts are made from 8 to 12 in. apart, 

 and, according to Christy, incisions every 8 in. will furnish 

 the whole of the available latex, no further flow being 

 obtained if additional incisions are subsequently made 

 between the previous series. The trees are usually tapped 

 only once, or at most twice, in the year on alternate sides. 



A V laiife or a gouge is generally used for making the 

 incisions, portions of the bark being excised. Cliristy, 

 however, has suggested an mcision method in which 

 shallow grooves, not reaching to the laticiferous tissue, 

 are cut in the bark by means of a V laiife with rounded 

 apex, and the latex is then liberated by a rowel pricker 

 with a thin sharp blj^de. This method has been very 

 favourably received both in West Africa and m Uganda, 

 as it gives a good jdeld of latex and tlie cuts heal 

 rapidly. Experiments conducted on Funtumia trees at 

 the Mamu Forest Reserve in Southern Nigeria showed 

 that incisions made by Christy's method healed almost 

 completely within a month or so, and it was considered 



