PHANEROGAMIC PARASITES 75 



with clover seed, usually of foreign origin. Dodder seed can 

 be readily detected when mixed with clover seed by its much 

 smaller size and different shape. Sifting with a suitable sieve 

 will remove most of the dodder seed, but this is a tedious 

 process for the farmer, and the purchase of clover seed 

 should be made on the understanding that it is free from 

 dodder seed. 



Carruthers, Journ. Roy. Hort. Soc. 



Garrigou, Comp. Rend. (1904) ; Journ. Board. Agric, 130, 



P- 33 ( r 97)- 



Flax dodder (Cuscuta epilinum, Weihe) is not an indi- 

 genous wild plant, neither is it yet naturalised, but is being 

 constantly introduced along with flax seed, and often causes 

 serious injury to flax. 



Flax seed free from dodder seed, which must be insisted 

 upon, is the only safeguard against this pest. 



Hop dodder {Cuscuta europaea, L.) attacks hops, nettles, 

 vetches, and other wild plants. 



Mistletoe. The common mistletoe (Viscum album, L.) is 

 too well known to require description. It is parasitic on the 

 branches of a considerable number of different kinds of trees, 

 and sometimes proves a serious source of injury when it 

 attacks fruit-trees, apple and pear more especially, as that 

 portion of a branch situated beyond the point occupied by 

 the mistletoe rarely produces good fruit. 



It is a difficult matter to protect orchard trees from attack 

 in a district where the mistletoe is common on poplars, etc., 

 as the seeds are conveyed by birds as previously stated. It 

 is not sufficient to cut off the tufts of mistletoe from a branch : 

 this method certainly retards the distribution of the parasite 

 by means of seed, but when a tuft is simply cut off close to 

 the branch upon which it is growing, those portions of the 

 parasite situated under the bark in course of time give origin 

 to other tufts. The only certain method is to remove each 

 branch below the point where the parasite occurs. This 

 method, although apparently drastic, is the proper one, 

 because, as already stated, that portion of a branch situated 

 beyond the point where a mistletoe is growing, produces 

 inferior fruit, if any. 



