THE 



TROPICAL AGRICULTURIST 



AND 



MAGAZINE OF THE 



CEYLON AGRICULTURAL SOCIETY. 



Vol. XXXIII, COLOMBO, AUGUST 15th, 1909, No. 2. 



THE LORANTHUS PARASITE. 



The genus Loranthus is represented 

 by seventeen species in this country, 

 seven of which are common upcountry, 

 whilst eight of the species are endemic, 

 or found only in Ceylon. 



Loranthus belongs to the group of 

 plants known as semi-parasites, that is 

 to say, it possesses green leaves of its 

 own, but is nevertheless dependent upon 

 some other plant for a portion of its 

 food supply. Its habit of growth is 

 closely similar to that of its near relative 

 the mistletoe. 



The seeds, which are distributed by 

 birds— and chiefly by the very small 

 flower-pecker which rejoices in the 

 name of Dicaeum erythrorhy neb urn- 

 germinate upon the branch of some tree 

 or shrub, particular host plants being 

 affected to some extent by particular 

 species of the Loranthus. Some of the 

 species seem to be almost indiscriminate 

 in their attentions, but a full study of 

 the different hosts of the different 

 species still remains bo be made. 



When the seedling germinates, instead 

 of forming roots like those of an ordi- 

 nary plant, it develops a special kind of 

 suckers known as haustoria, which pene- 

 trate beneath the bark of the tree 

 attacked by the parasite, and, lamifying 

 chiefly between the bark and the wood, 



absorb a portion of the nutriment which 

 the host had prepared for its own pur- 

 poses. If a tree is badly attacked in this 

 way the drain upon its resources may be 

 so great that it may become seriously 

 crippled or even eventually killed. 



Some prominence has recently been 

 given in the local Press to accounts of 

 the appearance of this parasite upon tea 

 at Nuwara Eliya. We may state at once 

 that we consider anything in the nature 

 of a scare on this account to be entirely 

 devoid of justification, It has been 

 Known for a considerable number of 

 years that more than one species of 

 Loranthus will attack tea if this crop is 

 neglected, or allowed to run for long 

 periods without pruning. As might be 

 expected, it is especially common to find 

 the parasite upon tea plants which have 

 been allowed to grow up as seed-bearers, 

 It is generally thought that, with a 

 moderate amount of care, healthy tea 

 bushes can be kept entirely free of the 

 Loranthus parasite. 



It so happens that some of the 

 commonest of the species of Loranthus 

 which are known to attack tea also 

 affect the species of Acacia which are 

 commonly planted amongst, or in the 

 neighbourhood of, tea at high levels. It 

 is therefore desirable that a watch 

 should be kept upon these as well as 

 upon the tea itself, and that any plants 



