302 



LANTANA IN CEYLON. 



BY 



T. Petch 

 Peradeniya, Ceylon. 



In Memoirs of the Department of Agriculture in India, Vol. V, 

 No. 6, Kao Sahib Y. Ramachandra Rao has presented a paper on Lan- 

 tana insects in India which is of interest to botanists, as it includes a 

 comprehensive account of the host plants, one at least of which, Lan- 

 tana aculeata, is a troublesome weed in many parts of the Eastern 

 Tropics. 



As regards the status of Lantana, Ceylon constitutes an exception 

 to the general experience. In Ceylon, Lantana aculeata is common 

 enough, but it is not looked upon as a troublesome weed. Indeed, 

 the tendency is rather to regard it as beneficial, since it rapidly takes 

 possession of waste ground and thereby prevents denudation or deter- 

 ioration of the soil by exposure. 



Ceylon, however, comes in for special consideration by investiga- 

 tors of the Lantana problem, as the possessor of a plant, Tithonia 

 diversifolia, which is alleged to kill out Lantana. This idea appears 

 to have originated about 1890, and it was given currency outside 

 Ceylon by Mr. John Ross, a resident in Hawaii, who published a note 

 on the subject in the Planters' Monthly (Bonolulu), vol. X, pp- 436, 

 437 (October, 1891). 



Mr. Ross had met Lieutenant-General Sir Allen Johnson " of the 

 British Army in India " and, on explaining to the latter how " Lan- 

 tana was fast getting a ruinous control of the best pasture lands," 

 was informed by him that in Ceylon " they were having a similar 

 experience to us, but that lately they were getting it under control 

 through the agency of a particular kind of sun-flower imported there." 

 In consequence, Mr. Ross communicated with Ceylon, and obtained 

 seeds of the sunflower in question, accompanied by a letter from 

 Trimen, from which the following extract was published (loc. cit.). 



" The plant referred to by Mr. Ross is, no doubt, the Californian 

 sun-flower, Tithonia diversifolia, the brilliantly yellow-flowered weed 

 so conspicuous on waste ground in Ceylon. 



" I have recently pointed out to several visitors here the curious 

 fact that, when growing along with Lantana, this gradually kills out 



