36o 
LORANTHUS AS A PARASITE ON HEVEA 
BRASILIENSIS. 
short time ago the Acting Conservator of Forests wrote to 
the Director of Agriculture stating that on a recent visit to Pahang 
he noticed many Para Rubber trees at Pekan affected by a parasitic 
growth of some kind, similar to mistletoe. The parasite was not 
confined to Para rubber, but other trees, among which Casuarinas 
and Mangosteens were noticed, were very badly attacked, Specimens 
were obtained and it was found that the parasite was a species of 
Loranthus. The particular species could not be determined owing to 
the condition of the material. It is quite possible that the parasite 
may be found on rubber trees in other districts, and a short account 
of it may therefore be interesting to planters. 
Loranthus is closely related to the European mistletoe. There 
aie many species, and they are all parasitic on trees, mostly in the 
tropics. The plants attach themselves to the branches of trees and 
form shrubby growths, often of a considerable size. The leaves are 
green, and usually of a leathery texture. Like all plants with green 
leaves, Loranthus can manufacture its own carbonaceous food, and it 
probably draws little more from the host-plant than supplies of 
water with the salts dissolved in it. It is therefore not a true para- 
site, for these derive all their nutriment from the plants on which 
they live, and on accounts of its partial independence it is called a 
semi-parasfte^ 
The mode of distribution is peculiar and interesting. Each 
fruit contains a large seed, around w r hich is a layer of a very viscid 
substance. The fruits are eaten by birds, which are fond of the 
pulpy fruit-coat. The seeds, however, are not eaten, ether because 
the sticky substance makes them difficult to swallow, or because 
they are distasteful on account of the large amount of tannin they 
contain. The bird gets rid of the seed by rubbing its bill against 
some convenient object, usually the branch of a tree. Here the seed 
adheres and germinates. The seedling puts out a root-like organ , 
and if the tree happens to be a suitable host it penetrates the bark 
and bores its way down to the wood. After a time lateral “roots” 
are put off from this primary “root” and grow along the branch 
between the wood and the bark. Buds arise from the upper side of 
those lateral “roots,” push their way outwards, emerge and from 
new branches. A shrub-like growth ultimately results. 
As a rule a species of Loranthus will not grow on any and every 
kind of tree, but has-a preference for certain kinds. Some species are 
more indiscriminate than others, and it is not at all surprising that 
one of them should have taken a liking to Hevea. In other tropical 
countries Loranthus attacks various plants of economic importance. 
For many years it has been a troublesome parasite on tea in India 
Burma and Ceylon. 
