July, 1908.] 



Saps and Exudations. 



order to prevent the actinic rays of 

 daylight from reaching the rubber. 



Prices of Rubber.— Although I do not 

 expect the present high prices of rub- 

 ber to last, there is very little reason 

 to suppose that the prices would go 

 down to any considerable extent for the 

 next few years to come. It now costs 

 us approximately 25 cts. Mex. to collect, 

 prepare and market one pound of 

 rubber, while under the old systems 

 in this country it has cost in some cases 

 as much as 7-1 cts. The price we can 

 get at present for rubber prepared on 

 the new system is $2-62 Mex. per lb. 

 Let us say that the prices go down 

 50 %, and we will still find rubber cul- 

 ture profitable. 



The goal we must work for is to pre- 

 pare as good a quality of rubber as is 

 possible. At the same time we must 

 endeavour to decrease the cost of pro- 

 duction by employing modern labour- 

 saving appliances and a carefully planned 

 system of work and management. 



Discussion. 

 The Chairman said that after such 

 an interesting paper he was sure that 

 there were some questions to be put to 

 Dr. Olsson-Seffer. 



Mr. J. C. Harvey : I would like to ask 

 if there is any special time for tapping 

 which you would recommend. I do not 

 think this was mentioned in your paper. 



Dr. Olsson-Seffer said that experi- 

 ence had proved that the best time of 

 tapping is in the wet season, when a 

 greater amount of latex is obtained, 

 and the incisions healed quicker. The 

 actual time naturally varies with the 

 geographical position of the plantation. 

 It may be said that as a rule tapping 

 should begin about 2 or 3 weeks after 

 the rains have set in. It is necessary to 

 give the tree a little time after the dry 

 season in order to permit the tree to 

 accustom itself to receive the larger 

 amount of water which always circulates 

 in the tissues after the rains. The trans- 

 piration is always larger immediately 

 after tapping, and if the tree is not 

 adjusted to a rajrid circulation it will 

 suffer. It generally takes about two 

 months for the incisions to heal, and if 

 we follow the plan suggested in the 

 paper not to tap again before the tree has 

 recuperated, we will be able to tap our 

 trees every second month as long as the 

 rains last. In a region with six months' 

 rainy season we thus can tap about three 

 times a year. If the trees are tapped 

 during the dry season the tree suffers 

 considerably, and instead of healing the 

 wounds remain open, and on the edges 

 an accumulation of cork takes place, 

 which makes the bark rough and uneven 



and greatly hampers future tappings. 

 During the # rainy season the trees are 

 also more immune to the attacks of 

 diseases than during the dry season. I 

 may here show some larvje which are the 

 worst enemies of the rubber planter. He 

 knows them well, but does not like to 

 talk about them. If the trees have been 

 cut badly, fungi settle in the wounds and 

 in conjunction with bacteria cause decay, 

 the smell of which attracts insects, 

 which deposit their eggs in the wounds, 

 and sometime afterwards the ravages of 

 the borer begin. This as well as other 

 diseases of the rubber tree can be pre- 

 vented, and it behoves the planter to be 

 on a constant look-out for these enemies. 



Mr. A. Aldasoro, speaking in Spanish, 

 said in part: "I have listened with 

 pleasure to the address of Dr. Olsson- 

 Seffer, and I extend to those in atten- 

 dance at this Convention my felicitations 

 upon their having so able and scientific 

 a man to discuss the subjects in which 

 they are interested. I wish the organiza- 

 tion which is now being formed all 

 success, and I assure you of my ever 

 earnest support." The Under-Secretary 

 thereupon left the meeting. — Year Boole 

 of the Rubber Planters' Association of 

 Mexico, 1907-1908. 



CACAO AS AN ADJUNCT TO 

 RUBBER CULTURE. 



By J. C. Harvey. 



(Paper read before the first meeting of 

 the Mexican Rubber Planters ' Associa- 

 tion on October 9th, 1907.) 



It is not attempted in this brief paper 

 to treat exhaustively with the cultivation 

 of either rubber or cacao, but to allude 

 tentatively to the advantages under 

 certain circumstances of the cultivation 

 of cacao as an adjunct to rubber grow- 

 ing. It should further be clearly under- 

 stood that such methods as may be fur- 

 ther referred to are only intended to 

 apply to the conditions of rainfall, soil 

 and temperature which exist in the 

 district in which the writer's conclusions 

 have been arrived at. 



From experimental plantings, made by 

 the writer at La Buena Ventura, of 

 cacao plants set out with rubber grow- 

 ing in full sun, there seems to be every 

 reason to doubt the success of the plant- 

 ings, for the following reasons : — The 

 rubber trees must have reached a 

 height of from 10 to 15 feet in order to 

 provide a proper shade even when the 

 rubber trees are in full foliage. This 

 would entail, after the planting of the 

 rubber, a waiting period of from three 

 to five years ; then again, the loss of 

 foliage of the Castilloatree becomes more 

 marked and the periodicity more fixed 



