AGRICULTURAL CLOVERS 71 



TnfoVium pratensc is quite unsuited for permanent 

 pastures, but should form a large proportion of an alternate 

 mixture. The great root-growth made during the two years 

 of its existence is the best possible preparation for the following 

 wheat crop. 



Red Clover is incapable of self-fertilisation, and the 

 Humble Bee is almost exclusively the medium by which 

 pollen is conveyed from anther to stigma. In Australia and 

 New Zealand, until the Humble Bee was introduced, seed 

 was rarely ripened, and the Red Clover sown in those colonies 

 was all imported, principally from England. 



The character and culture of Red Clover are so well 

 understood as to render further remark needless. 



For illustration, description, and chemical analysis, see 

 pages 182 and 183. 



TRIFOLIUM PRATENSE PERENNE 

 {Perennial Red Clover, or Con' Grass). 



This clover doubtless originated in a cross between 

 T'rifolium pratense, or Broad Clover, and Trifolium medium, 

 or Zigzag Clover.^ The latter has ne^'er been in commerce, 

 nor has it been grown as a crop, except for experimental 

 purposes. Yet some writers have fallen into the error of 

 confusing it with the true Perennial Red Clover, which in 

 Berkshu'e, Oxfordshu-e, Hampshire, and Wiltshire is known 

 as Cow Grass. In these counties Cow Grass is of immense 

 importance, and enters largely into the rotation of arable 

 land. The use of it is extending to other parts of England, 



' Trifolium medium. — The Cow Grass, or Zigzag Clover, of botanists is so called 

 from the decided zigzag growth. So distinct is the plant that it can scarcely be classed 

 -with Red Clover at all. The blossom is darker in colour than that of Trifolium 

 pratense, the head less dense, invariably growing on a long peduncle instead of 

 immediately adjacent to the leaf. The absence of the broad membranous stipule, 

 and the substitution of one which is long and narrow, terminating gradually in a spear- 

 like point, is also a marked characteristic, by which those who have once observed 

 this peculiarity are never again likely to mistake Trifolium medium for Trifolium 

 pratense. 



