MIXED CULTUEES. 61 



not stated, but since the Castilla at two years from planting is described 

 as only 3 to 8 feet high the conditions can not be regarded as favorable. 



The suggestion of Castilla for cacao shade is somewhat more rational, 

 since both trees are natives of the same regions of low elevation. As 

 noted elsewhere, rubber was first planted at Tapachula as shade for 

 cacao, but the experiment did not appear promising from the stand- 

 point of the cacao, and was abandoned. Some of the cacao trees still 

 remain, but they have never been vigorous and produce very little. 

 Other causes of failure may, of course, exist, but it seems certain that 

 the close planting which is now favored would make a rubber planta- 

 tion a very poor place for cacao, and there is every reason to believe 

 that, while cacao may not be benefited by shade, it may be seriously 

 injured b}^ sudden exposure to the sun, as happens when the leaves of 

 Castilla fall in the dry season. 



A further difficulty in the use of Castilla as shade is that, in order 

 to permit anything to grow under it, wide planting is necessary, and 

 this usually means a spreading low growth for the rubber trees, 

 generally considered undesirable, because it makes the extraction of 

 rubber difficult if it does not actually decrease the yield. In German 

 New Guinea, for example, Castilla has been planted 33 feet apart in 

 alternation with cocoa palms as shade for Liberian coffee. a It would 

 seem that all three trees must suffer under this arrangement, but it 

 will be interesting to learn which is injured least. 



Vanilla culture under Castilla has also been suggested and may be 

 worthy of consideration, since it is held that a period of dryness and 

 exposure to the sun is necessary for the proper ripening of the pods. 

 To successfully combine two or three cultures is, however, a difficult 

 matter, even when all are well known, but the supposed practicability 

 of such combinations has rested on ignorance of important details. 



Several years ago the culture of Castilla received a considerable 

 impetus from the recommendation of Dr. Daniel Morris, now imperial 

 commissioner of agriculture for the British West Indies, that Castilla 

 be used as shade for coffee and cacao in British Honduras, and an 

 estimated return was made of $5 per tree in eight or ten years or $125 

 per acre, to be repeated at intervals of five j^ears. 



According to Dr. Carl Sapper, a German scientist very familiar with 

 Central America, this advice has been followed with disastrous results. 

 He says: 



In fact, the developments thus far in the field of Castilloa culture show on the aver- 

 age very little in the way of favorable results. Particularly does it seem to have failed 

 completely when it has been combined with other tree cultures in order to lessen the 

 expenses of opening rubber plantations. Thus, on the advice of the well-known 

 English botanist, D. Morris (then in Jamaica), rubber trees were planted for shade 

 in the coffee plantation San Felipe, near El Cayo, in British Honduras, and the result 



« Der Tropenpflanzer, 7:21, January, 1903. 



